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Developing efficient electrocatalyst in sulfides for hydrogen evolution reaction (HER) still poses challenges due to the lack of understanding the role of sulfide heterointerface. Here, we report a sulfide heterostructure RuSx/NbS2, which is composed of 3R‐type NbS2 loaded by amorphous RuSx nanoparticles with S−S bonds formed at the interface. As HER electrocatalyst, the RuSx/NbS2 shows remarkable low overpotential of 38 mV to drive a current density of 10 mA cm−2 in acid, and also low Tafel slope of 51.05 mV dec−1. The intrinsic activity of RuSx/NbS2 is much higher than that of Ru/NbS2 reference as well as the commercial Pt/C. Both experiments and theoretical calculations unveil a reversed charge transfer at the interface from NbS2 to RuSx that driven by the formation of S−S bonds, resulting in electron‐rich Ru configuration for strong hydrogen adsorption. Meanwhile, electronic redistribution induced by the sulfide heterostructure facilitates hydrogen spillover (HSo) effect in this system, leading to accelerated hydrogen desorption at the basal plane of NbS2. This study provides an effective S−S bond strategy in sulfide heterostructure to synergistically modulate the charge transfer and adsorption thermodynamics, which is very valuable for the development of efficient electrocatalysts in practical applications. [ABSTRACT FROM AUTHOR]

Efficient and sustainable electrocatalysts for the hydrogen evolution reaction (HER) using earth-abundant elements are crucial for eco-friendly hydrogen production, particularly under neutral and acidic conditions. In metallic alloys, careful selection of alloying elements and control over the composition, morphology, electronic structure, and structural defects are expected to tune electrocatalytic activities. In this work, we introduce a two-step electrodeposition approach to create a 3D porous trimetallic alloy, Cu@Cu–Ni–Co, exhibiting excellent catalytic activity and stability for HER in neutral and acidic environments. The process begins with the electrodeposition of 3D copper dendrites, which was found to be crucial for the catalyst's mechanical stability, followed by the deposition of the trimetallic alloy, where copper's inclusion promotes the controlled growth of the alloy's 3D structure. The Cu@Cu–Ni–Co catalyst outperforms Cu@Ni, Cu@Co, Cu@Ni–Co, and GC@Cu–Ni–Co electrocatalysts in neutral and acidic conditions, highlighting the importance of the developed electrodeposition approach. In 1.0 M phosphate-buffer solution (PBS), Cu@Cu–Ni–Co achieves a current density of 10 mA cm−2 at an overpotential of 275 mV with a Tafel slope of 134 mV dec−1, maintaining remarkable stability in both acidic and neutral conditions at high current densities (48–165 mA cm−2) for up to 50 h without any decline in activity. [Display omitted] • Developed a two-step electrodeposition method to create a 3D porous Cu@Cu–Ni–Co alloy, optimizing HER performance in neutral and acidic conditions. • Used initial copper dendrite deposition for enhanced mechanical stability and precise microstructural control of the trimetallic alloy. • Achieved an overpotential of 275 mV with the Cu@Cu–Ni–Co catalyst, surpassing Cu@Ni, Cu@Co, Cu@Ni–Co, and GC@Cu–Ni–Co. • Maintained high stability at current densities of 48–165 mA cm−2 for 50 h without degradation, under both acidic and neutral conditions. • Demonstrated excellent compatibility and effectiveness on various substrates including glassy carbon, nickel foam, and ITO. [ABSTRACT FROM AUTHOR]

Single-atom catalysts exhibit immense potential across diverse reactions, yet their synthesis and stability in acidic environments pose significant challenges. Herein, we introduce a facile one-step hydrothermal approach to fabricate Ru single-atom alloy catalysts (Ru SAAC) through the reaction of Ru and Ti precursors, followed by annealing in an argon atmosphere. Analysis via extended X-ray absorption fine structure spectroscopy and aberration-corrected scanning transmission electron microscopy confirms the atomically dispersed Ru alloy catalyst anchored on a TiO 2 support. Remarkably, Ru SAAC demonstrates exceptional electrocatalytic performance in the iodide oxidation reaction (IOR), achieving a benchmark current density of 10 mA/cm2 at a mere voltage of 0.64 V in acidic conditions within a three-electrode electrolyzer setup. Surpassing nanoscale Ru/TiO 2 and RuO 2 /TiO 2 counterparts, Ru SAAC exhibits the highest voltage efficiency (84.4%), lowest Tafel slope (36 mV/dec), and lowest overpotential (100 mV) under identical experimental conditions. This method enables facile control over Ru morphology. It enhances the kinetics and thermodynamic favorability of Ru SAAC in acidic media, opening avenues for synthesizing diverse transition metal-based single-alloy catalysts for varied applications. [Display omitted] • A simple one-step hydrothermal method to fabricate Ru single-atom alloy catalysts. • Achieving a low potential of 0.64 V at 10 mA/cm2, outperforming other Ru/TiO₂ catalysts. • Energy-saving iodide oxidation reaction favorable for coupling hydrogen production. • It gives highest voltage efficiency (84.4%), lowest Tafel slope (36 mV/dec), lowest overpotential. • Method offers easy control over Ru morphology, enhancing kinetics and stability in acidic media. [ABSTRACT FROM AUTHOR]

Photo‐driven cross‐coupling of o‐arylenediamines and alcohols has emerged as an alternative for the synthesis of bio‐active benzimidazoles. However, tackling the key problem related to efficient adsorption and activation of both coupling partners over photocatalysts towards activity enhancement remains a challenge. Here, we demonstrate an efficient interface synergy strategy by coupling exposed oxygen vacancies (VO) and Pd Lewis acid sites for benzimidazole and hydrogen (H2) coproduction over Pd‐loaded TiO2 nanospheres with the highest photoredox activity compared to previous works so far. The results show that the introduction of VO optimizes the energy band structure and supplies coordinatively unsaturated sites for adsorbing and activating ethanol molecules, affording acetaldehyde active intermediates. Pd acts as a Lewis acid site, enhancing the adsorption of alkaline amine molecules via Lewis acid‐base pair interactions and driving the condensation process. Furthermore, VO and Pd synergistically promote interfacial charge transfer and separation. This work offers new insightful guidance for the rational design of semiconductor‐based photocatalysts with interface synergy at the molecular level towards the high‐performance coproduction of renewable fuels and value‐added feedstocks. [ABSTRACT FROM AUTHOR]

To combat the energy crisis and environmental pollution, developing renewable energy technology such as hydrogen (H2) production is necessary. The sulfur–iodine thermochemical cycle has high commercial potential in conducting hydrogen iodide (HI) splitting for H2 generation, but it requires high‐temperature conditions. In comparison, photocatalytic HI splitting of halide perovskites is non‐polluted and low‐cost for H2 production at room temperature. Herein, an in situ constructed multidimensional bismuth (Bi)‐based 3D/2D EDABiI5/MA3Bi2I9 perovskite heterojunction is developed first by synergistically integrating dimensionality control with heterostructure engineering. Accordingly, the optimal EDABiI5/MA3Bi2I9 without any co‐catalysts exhibits the H2 evolution rate of 213.63 µmol h−1g−1 under irradiation. Equally importantly, interfacial dynamics of solid/solid and solid/liquid interfaces play a crucial role in photocatalytic performance. Therefore, using temperature‐dependent transient photoluminescence and electrochemical voltammetric techniques, it is confirmed that the exciton transportation of EDABiI5/MA3Bi2I9 is accelerated by stronger electronic coupling arising from an enhanced overlap of electronic wavefunctions. Moreover, the effective diffusion coefficient and electron transfer rate of EDABiI5/MA3Bi2I9 demonstrate efficient heterogeneous electron transfer, resulting in improved photocatalytic hydrogen production. Consequently, the in situ formation of perovskite heterostructures studied by a combination of photophysical and electrochemical techniques provides new insights into green hydrogen evolution and interfacial interaction dynamics for commercial applications of solar‐to‐fuel technology. [ABSTRACT FROM AUTHOR]

Mesoporous catalysts with a high specific surface area, accessible pore structures, and appropriate band edges are desirable for optimal charge transfer across the interfaces, suppress electron‐hole recombination, and promote redox reactions at the active sites. The present study demonstrates the rational design of mesoporous ZnFe2O4@g‐C3N4 magnetic nanocomposites (MNCs) with different pore sizes and pore volumes following a combination of facile thermal itching and thermal impregnation methods. The MNCs preserve the structural, morphological, and physical attributes of their counterparts while ensuring their effectiveness and superior catalytic capabilities. The morphological analysis confirms the successful grafting and confinement of ZnFe2O4 nanoparticles with the polymeric g‐C3N4 nanosheets to form heterojunctions with numerous interfaces. The MNCs possess uniformly distributed small mesopores (pore size <4 nm), ample active sites, and a high specific surface area of 62.50 m2/g. The mesoporous ZnFe2O4@g‐C3N4 notably improve hydrogen evolution rate and methylene blue dye degradation. The optimal loading weight of ZnFe2O4 is 20 %, in which the MNCs display the highest hydrogen evolution rate of 1752 μmol g−1 h−1 and photo‐Fenton dye degradation rate constants of 0.147 min−1, upon solar‐light illumination. Furthermore, the photocatalysts demonstrate recyclability over five consecutive cycles, confirming their stability, while easy separation using a simple magnet underscores practical utility. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Development of heterogeneous molecular photocatalysts for promising light‐driven hydrogen evolution reaction (HER) is highly demanding but still challenging. Here, we report the blue‐greenish emitting dinuclear metal–organic halides as photocatalyst by incorporating site‐specific single copper(I) atoms that exhibit an efficient carbon‐negative H2 production. Interestingly, the electronic properties, including the spin and charge density of central Cu(I) active site, can be triggered by substituent modulation in metal–organic halides, which greatly affect the exciton dissociation kinetics and thus the HER reactivity. The optimized spin density in these heterogeneous photocatalysts drastically boosts the hydrogen production rate from 1250 to 3130 μmol·g–1·h–1. Our molecular strategy provides a platform that rationally facilitates electronic modulation of copper(I) atoms, tunes the macroscopic optoelectronic properties of photocatalysts and boosts carbon‐negative HER activity, extending the boundaries of conventional molecular‐based photocatalysts. [ABSTRACT FROM AUTHOR]

Achieving a high dispersity of deposited transition metal is crucial in the anodization preparation of noble‐metal‐free composites for photocatalytic hydrogen generation. Herein, for the first time, an in situ ion pumping anodization method is proposed to confine single‐atom Fe within the spatially ordered structure of anodized TiO2 nanotubes (TNT), assisted by ferric sodium salt of ethylenediaminetetraacetic acid (EDTA) as an "ion pump" to deliver Fe3+ toward anodes. Both experimental and theoretical calculations confirm that highly dispersed single‐atom Fe can interact with single‐electron‐trapped oxygen vacancies (SETOV), effectively reducing the oxygen vacancy concentration in TiO2 nanotubes. This reduction promotes efficient charge carrier separation through the Fe(III)/Fe(II) pathway and enhances hydrogen desorption, ultimately boosting the photocatalytic hydrogen evolution performance. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Development of heterogeneous molecular photocatalysts for promising light‐driven hydrogen evolution reaction (HER) is highly demanding but still challenging. Here, we report the blue‐greenish emitting dinuclear metal–organic halides as photocatalyst by incorporating site‐specific single copper(I) atoms that exhibit an efficient carbon‐negative H2 production. Interestingly, the electronic properties, including the spin and charge density of central Cu(I) active site, can be triggered by substituent modulation in metal–organic halides, which greatly affect the exciton dissociation kinetics and thus the HER reactivity. The optimized spin density in these heterogeneous photocatalysts drastically boosts the hydrogen production rate from 1250 to 3130 μmol·g–1·h–1. Our molecular strategy provides a platform that rationally facilitates electronic modulation of copper(I) atoms, tunes the macroscopic optoelectronic properties of photocatalysts and boosts carbon‐negative HER activity, extending the boundaries of conventional molecular‐based photocatalysts. [ABSTRACT FROM AUTHOR]

Constructing catalysts that simultaneously contain single atom/metal nanocluster active sites is a promising strategy to enhance the original catalytic behavior and accelerate the catalysis involving multi‐electron reactions or multi‐intermediates. Herein, the pyrolysis‐free synthetic method is developed to integrate single atoms and nanoclusters towards highly satisfactory catalytic performances for both acidic and alkaline hydrogen electrocatalysis. The controllable pyrolysis‐free strategy allows the precise modulation of the active centers, realizing the optimization of the adsorption energy and the regulation of the synergistic active components. Specially, the as‐prepared catalysts with hybrid single‐atom/nanocluster sites exhibited superior catalytic activities for hydrogen evolution in both acidic and alkaline media with low over‐potentials at −10 mA cm−2 of 25 mV and 8.6 mV, respectively, combining with outstanding durability towards high current density and methanol poisoning. This work developed a universal synthetic strategy for the single atom/nanocluster synergy systems and addressed the superiority of hybrid single‐atom/nanocluster sites. [ABSTRACT FROM AUTHOR]

Uncontrolled dendrite growth and electrolyte‐induced intricate parasitic reactions are two great challenges that hinder the commercial applications of aqueous zinc‐ion batteries. Herein, a synchronous modulation strategy for Zn2+ interfacial migration behavior and electrolyte microenvironment is proposed by constructing a functional lanthanum hydroxide aerogel (LAG) interface layer on Zn anode surface. The in situ derivation of ion‐conducting zinc hydroxide sulfate (ZHS) from LAG layer results in the spontaneous generation of a hierarchic interface layer during the plating process, where the high Zn2+ selectivity of the upper dense ZHS layer can limit SO42− migration and allow for fast Zn2+ interfacial migration kinetics, while the aerogel layer with well‐defined nanochannels near the anode side can homogenize Zn2+ distribution, thus leading to the effective suppression of both dendrites and side reactions. Additionally, the pH microenvironment of the acidic electrolyte can be synchronously regulated by slightly soluble La(OH)3 aerogel, further inhibiting electrolyte corrosion and HER. Consequently, the modified Zn anode delivers highly reversible Zn plating/stripping and low‐voltage hysteresis, and the high areal‐capacity Zn||MnO2 full cells demonstrate considerable electrochemical performances under high Zn utilization conditions. This functional aerogel‐driven synchronous modulation strategy of Zn2+ migration behavior and electrolyte microenvironment provides new insight for stabilizing Zn metal anodes. [ABSTRACT FROM AUTHOR]

Developing effective methods to enhance the photocatalytic hydrogen evolution activity of MoS 2 -based cocatalysts remains a challenge due to their inherently low activity. This study utilized a simultaneous vulcanization-nitrogenization solid-phase reduction method to prepare MoN 1.2x S 2-1.2x cocatalyst. The experimental and theoretical results indicate that the N-doped atoms triggered the H+ reduction catalytic activity on the (002) plane of the MoN 1.2x S 2-1.2x cocatalyst. Additionally, the MoN 1.2x S 2-1.2x cocatalyst significantly improves the hydrogen evolution reaction to form heterostructures with g-C 3 N 4 nanosheets (denoted as MoN 1.2x S 2-1.2x @g-C 3 N 4). Benefiting from the abundance of exposed catalytic sites and the excellent intrinsic charge separation characteristics of MoN 1.2x S 2-1.2x , an optimized MoN 1.2x S 2-1.2x @g-C 3 N 4 hybrid (5 wt%) exhibits an extraordinary photocatalytic H 2 evolution rate of 360.4 μmolg−1h−1, which is 19.6 and 14.3 folds higher than the g-C 3 N 4 and 5 wt% MoS 2 @g-C 3 N 4 , respectively. The simultaneous vulcanization-nitrogenization solid-phase reduction method offers a new and effective approach to dope N atoms in MoS 2 cocatalysts for photocatalytic applications. [Display omitted] • The doped N atoms triggered the catalytic activity on the (002) plane of MoS 2. • The MoN 1.2x S 2-1.2x reduces the charge transfer impedance at the interface. • The constructed heterostructure provides a transfer channel for carriers. • The 5 wt% MoN 1.2x S 2-1.2x @g-C 3 N 4 exhibits the HER of 360.4 μmolg−1h−1. [ABSTRACT FROM AUTHOR]

Generating a clean and sustainable hydrogen using the naturally available electrocatalysts to split water is among the primary energy resources adopted by the global industries. Transition metal dichalcogenides such as tungsten disulfide (WS 2) provide abundant active sites to foster hydrogen evolution reaction (HER). A simple hydrothermal process was employed to synthesize WO 3 ·H 2 O (hydrated tungsten trioxide) and WO 3 nanoparticles. The inclusion of WS 2 into the oxide has enhanced the ionic movement, which has improved the catalytic performance of the composite. The hydrophilic nature of WO 3 has facilitated the conversion of water molecules into adsorbed hydrogen, which was then spilled over the HER active sites of WS 2 to produce hydrogen. Thus, the WO 3 ·H 2 O/WS 2 catalyst achieved a current density of 10 mA cm−2 at an overpotential of 383 mV with Tafel slope of 77 mV dec−1 under neutral conditions and a hydrogen evolution rate of 0.33 mmol h−1 cm−2 at −0.5 V versus RHE. [Display omitted] • A tungsten-based composite, WO 3 ·H 2 O/WS 2 , was synthesized using a facile hydrothermal method at a relatively low temperature. • An overpotential of 383 mV at a current density of 10 mA cm−2 in HER is achieved under neutral conditions. • The estimated rate of hydrogen evolution is 0.33 mmol h−1 cm−2 at a potential of −0.5 V versus RHE. [ABSTRACT FROM AUTHOR]

A convenient, non-toxic, and low-cost tin dioxide (SnO2)/nickel oxide (NiO)/reduced graphene oxide (rGO) nanocatalytic electrode was investigated, which can effectively promote the hydrogen evolution reaction and can also be used to construct a sensitive winter wheat cold-tolerant RNA sensor. Due to the good synergy and photocurrent generation between SnO2 and NiO, which accelerates the electron transfer and catalyzes the hydrolysis reaction, the resultant data for the hydrogen evolution reaction in alkaline environment of this material are very impressive, with cathodic current densities of up to 10 mA cm−2. The marvelous heterostructures and photovoltaic properties form a signal amplification system, which enables the nanocomposites to have an excellent linear sensitivity in low-concentration RNA solutions. The single-stranded complementary RNA of the target RNA was immobilized on the surface of the nanocomposites, which enabled the materials to recognize the target RNA under enzyme-free conditions. The test results showed that the modified electrode materials had good single detection performance in a wide linear range from 0.1 nM to 2 mM, with the limit of detection (LOD) of 0.078 nM. The developed nanocomposite electrode has good performance in hydrogen evolution and winter wheat cold-resistant RNA detection, and is a bifunctional device with superior performance. [ABSTRACT FROM AUTHOR]

The synthesis of supported multielement transition metal phosphides (TMPs) to exploit the synergistic interplay between electronic and geometric effects resulting from the presence of different metals in the material and the arrangement of heterogeneous atoms is pivotal for reducing metal content while offering multiple active sites. However, the integration of Ni, Co, and P, for example, into a nanostructured carbon network to develop self‐supporting NixCoyP bimetallic phosphides is limited by several factors, including the synthesis and the discrepancy between the crystal structure of the respective monometallic phosphides. Moreover, conventional synthesis of supported TMPs often separates nanoparticles, support and phosphidation steps, which do not allow tailoring of physical and catalytic properties via particle support, electronic and geometric interactions. Herein, an innovative solid‐state, ex situ phosphidation‐free approach tailored to synthesize a library of self‐supporting NixCoyP TMPs in N,S,P‐modified nanostructured carbon networks generated together with NixCoyP particles is presented. Extensive multivariate characterization validates the unique properties of NixCoyP bimetallic materials with enhanced electrocatalytic performance for the hydrogen evolution reaction and the selective electroconversion of biomass‐derived 5‐hydroxymethylfurfural (5‐HMF) to value‐added 2,5‐furandicarboxylic acid (FDCA) with 90–100% Faradaic efficiency. Overall, the synthesis expands the possibilities for tailoring the microstructure of supported TMPs for improved physical/catalytic properties. [ABSTRACT FROM AUTHOR]

The demand for energy surpasses the available supply, leading to various economic, social, and environmental consequences. Hydrogen is one of the most clean and renewable source for energy. Therefore, the electrocatalytic hydrogen evolution reaction (HER) presents a promising eco-friendly approach for generating sustainable hydrogen energy. However, in alkaline conditions, HER encounters slow kinetics due to challenges associated with hydrogen adsorption and hydrolysis. In this article, thin Ni films were synthesized using the electrodeposition technique from citrate electrolyte. Their suitability as electrocatalysts for the hydrogen evolution reaction (HER) in a 1 M NaOH solution was estimated. This research investigates how the uniform magnetic field and temperature affect the process of nickel electrodeposition from a citrate bath and its subsequent influence on surface morphology and catalytic properties for the hydrogen evolution reaction (HER). Additionally, alterations in surface material wettability were examined based on changing the temperature during using the magnetic field for the electrodeposition process and shows how this effect on the catalytic performance towards HER. The outputs show that using the magnetic field for fabrication of Ni thin films at room temperature enhances the surface morphology and its catalytic performance for HER. However, the study reveals that using the temperature for Ni electrodeposition improves its catalytic performance independently of the magnetic field, whereas combining temperature with the magnetic field for Ni thin film fabrication diminishes their catalytic performance for the hydrogen evolution reaction (HER). The nickel thin film produced at 25 °C under the influence of a magnetic field, whether parallel or perpendicular, demonstrates the lowest overpotential of − 268 mV to achieve a current density of 10 mA cm−2. Additionally, it exhibits the smallest Tafel slope values of 106 mV dec−1 and 128 mV dec−1 for the parallel (Bǁ) and perpendicular (BꞱ) directions, respectively. However, the magnetic field effect diminishes at elevated temperatures. Nickel thin films prepared at 35 °C under the influence of perpendicular (BꞱ) and parallel (Bǁ) directions exhibit higher overpotential values of − 314 mV and − 322 mV, respectively. [ABSTRACT FROM AUTHOR]

The Co2O3-Chitosan composite (Co@Chitosan) nanoparticles were synthesized through a green approach. The composite under investigation was characterized by various analytical methods, including scanning electron microscopy (SEM), transmitted electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and atomic force microscope (AFM) confirming the preparation step. The modified composite's performance was evaluated for its potential applications in nitrite sensing and hydrogen production by utilizing diverse electrochemical methodologies. The Co2O3-Chitosan that has been modified exhibits a linear detection range of 0.25–100 µM and a limit of detection (LOD) of 0.117 µM with a response time of approximately 5 s using the amperometry technique. Furthermore, the utilization of Co2O3-Chitosan composite as a proficient catalyst for hydrogen generation in an alkaline environment was implemented. The electrode exhibited enduring stability in fuel generation and heightened energy safeguarding. The current density of the electrode was observed to attain a value of η 50 at − 0.55 and − 0.43 V (versus RHE) for Co2O3 and Co@Chitosan, respectively. The study investigated the durability of electrodes during extended periods of constant potential chronoamperometry lasting 6 h. The Co2O3 and Co@Chitosan exhibited a reduction in initial current by 11% and 7%, respectively. [ABSTRACT FROM AUTHOR]

The burgeoning field of conjugated microporous polymers (CMPs) has generated widespread interest due to their potential as photocatalysts for hydrogen production from water. Nevertheless, their photocatalytic performance is sometimes hindered by inadequate charge separation and transfer, coupled with rapid charge recombination. Herein, a strategy to enhance photocatalytic performance via the customization of π‐bridges through the modulation of heteroatoms in a series of donor‐π‐acceptor (D‐π‐A) CMPs is proposed. This affords optimized energy levels and improved charge separation and transfer, thus boosting photocatalytic efficiency. Among various heteroatom substitutions, S‐doped CMP (10 mg) demonstrates the highest photocatalytic hydrogen evolution rate of 203 µmol h−1 (AQY450nm = 7.4%) under visible light irradiation. Subsequent experimental analysis reveals its superior photocatalytic performance can be largely related to its minimized exciton binding energy, facilitated charge transfer efficiency, and impeded charge recombination among these heteroatom‐doped D‐π‐A CMPs. This research paves the way for the rational design and modification of organic semiconductors for advanced solar‐driven photocatalysis by promoting charge separation and transfer. [ABSTRACT FROM AUTHOR]

The process of transforming solar power into hydrogen fuel through photoelectrochemical water splitting is a highly viable strategy for producing hydrogen in an environmentally friendly and sustainable manner, offering a long-term solution to the worldwide energy crisis. Therefore, the need for high-performance photoelectrodes is critical for optimizing the transformation of solar energy into hydrogen fuel. Herein, a simple citrate sol-gel technique was employed to fabricate magnesium iron oxide (MgFeO 3) for its potential use in photoelectrochemical water splitting. A detailed analysis was undertaken using techniques such as XRD, FESEM, XPS, PL, EDX, and UV–Vis spectrophotometry to uncover the fundamental physicochemical and optoelectronic aspects of the MgFeO 3 perovskite material. The MgFeO 3 photoelectrode manifests superior PEC characteristics as evidenced by the optimal photocurrent density of 4.5 mA cm−2 achieved at a potential of 1.2 V vs. RHE, and a commendable solar-to-hydrogen conversion efficiency of 0.97%. EIS studies provided evidence of improved charge transfer kinetics and decreased recombination rates in the MgFeO 3 photoelectrode. In addition, extended reliability evaluations utilizing chronoamperometry verified consistent operation for 10 h at a photocurrent density of 3.5 mA cm−2, demonstrating the long-term durability of MgFeO 3 in PEC water splitting. These results emphasize the considerable promise of MgFeO 3 perovskite as a proficient and robust photoelectrode substance for PEC water-splitting applications. [Display omitted] • Developed MgFeO 3 perovskite nanostructures using a facile citrate sol-gel method. • High photocurrent density of 9.1 mA cm⁻2 at 1.2 V vs. RHE under visible light irradiation. • Demonstrated a solar-to-hydrogen conversion efficiency of 0.97% that showcase the material's efficiency. • MgFeO 3 material exhibited outstanding long-term stability under prolonged visible light exposure. [ABSTRACT FROM AUTHOR]

Porphyrin and its derivatives have been seen as a type of potential organic photocatalyst for photocatalytic hydrogen evolution. Substituent regulation as a simple method can effectively regulate the photoelectric characteristic of organic semiconductors. Herein, we designed three porphyrin derivatives attached with different substituents (PP‐NH2, PP‐OH and PP‐COOH). Through a facile substituent optimization strategy, the photoelectric properties of these porphyrin derivatives show an obvious difference, which leads an optimized photocatalytic hydrogen evolution efficiency. The porphyrin derivative with carboxyl presents a reduced impedance, and a better charge separation. Compared to the amino group, PP‐COOH with carboxyl, achieved a high hydrogen evolution rate of 2.20 mmol g−1 h−1 (over 20 times than that of PP‐NH2). Moreover, enhanced stability was observed in PP‐COOH rather than PP‐OH, because of the lower HOMO energy level. And the ionization of carboxyl in water negatively charges the porphyrin derivatives and forms a relatively stable sol. This result further increases the operation stability of PP‐COOH, during photocatalytic hydrogen evolution. This study presents a promising design strategy for long‐lifetime photocatalysts for hydrogen evolution. [ABSTRACT FROM AUTHOR]

Metal/MXene‐based materials show broad prospects in energy conversation through the strong metal‐support interaction (SMSI). However, the difficulty and harshness of synthesis heavily limit their further application. Herein, using Lewis acidic molten salt to etch MAX as a precursor of MXene, a more convenient and safer strategy is designed to in situ construct the MXene‐supported CoIr nanoalloy (CoIr/MXene) catalyst through Ti─O─M bond. The special layered structure and oxygen‐containing functional group of MXene regulate the SMSI upon CoIr nanoalloys. Moreover, the contact angle and in situ Raman test results exhibit good interface hydrophilicity of MXene, enhancing the water adsorption on interfaces, and accelerating the mass transfer process. As a result, CoIr/MXene shows high hydrogen evolution reaction (HER) performance, which only needs overpotentials of 34 and 50 mV to drive a current density of 10 mA cm−2 in alkaline and acidic media, respectively, with excellent stability. Especially, in alkaline media, CoIr/MXene possesses 6 times higher HER mass activity (4.297 A mgIr−1) than commercial Pt/C catalysts (0.686 A mgPt−1) at the potential of 50 mV, indicating larger active site density and intrinsic activity for CoIr/MXene. This work expands the application of the molten salt assist etching strategy and provides new insight for the development of metal/MXene‐based catalysts. [ABSTRACT FROM AUTHOR]

Photocatalysis is an emerging technology to address environmental pressure and energy shortages by converting solar energy into chemical energy in an efficient manner. In recent years, many review articles focused on LDH-based heterojunctions and their contributions to photocatalytic hydrogen production, CO 2 conversion, and organic degradation, but no review paper considered NiAl-LDH-based photocatalysts. Thus, our study introduces a comprehensive overview of the synthesis approaches, structural analysis, morphological characteristics, optical properties, and mechanism insights of NiAl-LDH-based hybrids and their powerful capacity for H 2 evolution. Furthermore, particular attention is given to the recent modification strategies, including metal doping, Type II, p-n, and Z/S-scheme heterojunctions. These technologies played a vital role in boosting the catalytic behavior of NiAl-LDH through reinforcing the oxidation potential, expanding the solar light absorption, strengthening catalyst stability, and enhancing the charge dynamic. This summarization relied primarily on the DFT calculations to justify and understand the photocatalytic mechanisms of the NiAl-LDH-based heterostructure. Special consideration is paid to the outstanding performance of NiAl-LDH-based photocatalysts for hydrogen evolution under solar light. By linking the previous outcomes with our future perspectives, this review attempts to encourage further investigations and developments in NiAl-LDH-based photocatalysts for sustainable H 2 generation, emphasizing their potential to solve environmental and global energy problems. • This review summarizes the latest trends in NiAl-LDH-based heterojunctions. • The synthesis and characterization techniques of NiAl-LDH-based hybrids were discussed. • Some modification strategies to boost the catalytic activity of NiAl-LDH were introduced. • Our work employed DFT calculations to justify the catalytic mechanisms of NiAl-LDH. • The NiAl-LDH-based photocatalysts exhibited excellent capacity for hydrogen evolution. [ABSTRACT FROM AUTHOR]

g-C 3 N 4 , a well-known semiconductor is widely used for photocatalysis because of its renowned and special properties. It is a nonmetallic polymeric material that is abundant in sources and easy to prepare, making it an attractive choice for photocatalysis that responds to visible light. However, due to various intrinsic structural and chemical drawbacks, it is very far from further applications. Herein, we used sucrose to modify the physicochemical characteristics of ordinary g-C 3 N 4 to prepare a carbon self-doped g-C 3 N 4 (Cn-MA) material through co-polycondensation with melamine and applied it for hydrogen production. The characterization showed that the addition of sucrose resulted in a narrowed band gap, widened absorption range, enhanced photoresponse, and photogenerated charge carrier separation. Furthermore, the prepared material was applied for hydrogen production activity, which revealed that it has higher photocatalytic performance than pristine g-C 3 N 4. The H 2 production rate of the optimized material (C 7.5 -MA) was recorded as 7.3 times greater than that of pure g-C 3 N 4. Through cycling tests, the stability of C 7.5 -MA was examined. The results showed that, even after four consecutive cycles, no apparent drop in its performance was observed. Additionally, here the mechanism of hydrogen production is also discussed. [Display omitted] • C-doped g-C 3 N 4 is prepared by Co-polycondensation of Melamine and Sucrose. • The photocatalytic H 2 evolution activity of C 7.5 -MA is 7.3 times higher than that of pristine g-C 3 N 4. • The morphology and chemical composition of pristine g-C 3 N 4 are not affected by carbon doping. • A negligible decrease in the photocatalytic performance of C 7.5 -MA is observed after 4 consecutive cycles. [ABSTRACT FROM AUTHOR]

The production of highly active and inexpensive electrocatalysts for the hydrogen evolution process is a need of time to meet the high demands for sustainable and clean energy. Transition metal (TM) doped single-atom catalysis is an alternative to precious metal catalysis thereby paving the way to commercial scale, and sustainable hydrogen generation. TM based efficient electrocatalysts possess several key features, including a low overpotential for the hydrogen evolution process (HER), excellent catalytic activity, high stability, and low cost. In the current study, first row TM (Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, & Zn) doped dioxaporphyrin (DOP) have been screened for hydrogen evolution reaction. The HER activity has been explored on the most stable spin states of each HTM@DOP. The stability of designed complexes have been confirmed through thermodynamic analysis and it has been found that all designed HTM@DOP complexes are thermodynamically stable with adsorption energies ranging from (−2.16 to −10.07 eV). The HFe@DOP complex has displayed the best catalytic activity for the hydrogen evolution process, with an optimal ΔG H value of −0.04 eV. In view of frontier molecular orbitals (FMOs) study, doping caused noticeable changes in the conductivities of HTM@DOP complexes. Additionally, the density of states (DOS) analysis for designed HTM@DOP complexes has been perfectly correlated with the FMO study. All TM-doped complexes have further been examined through charge transfer analysis, specifically natural bond orbitals (NBO) analysis and electron density difference (EDD). The interactions have been investigated through the quantum theory of atoms in molecules (QTAIM analysis) and noncovalent interactions (NCI analysis). The results reflect that TM-doped dioxaporphyrin are potential single atom electrocatalysts for HER activity. The theoretical study offers fresh insight for the experimentalists to construct such cost-effective electro-catalysts and expand the scientific community's grasp of the HER catalytic mechanism at the atomic and molecular level. [Display omitted] • Investigations on HER activity of first row transition metals doped DOP complexes. • Adsorption energy analysis based stability of HTM@DOP complexes. • Iron (Fe) as an efficient performer in HER due to least Gibbs free energy (G H = −0.050ev). • Transition metal doping increased the conductivity of DOP surface. [ABSTRACT FROM AUTHOR]

In this research, we present a novel facile, scalable, and template-free technique of synthesizing graphitic carbon nitride (g-C 3 N 4) nanotubes for generating hydrogen through photocatalysis. The hybrid technique involves a two-fold mixing of the precursor materials melamine (M) and cyanuric acid (CA), involving ball milling followed by solution mixing. By varying the M:CA molar ratios, different compositions of g-C 3 N 4 nanotubes were fabricated. The study focused on examining the surface characteristics and the photocatalytic hydrogen evolution performance of these nanotubes. Nanotubes with high specific surface area of 206 m2 g−1 for M:CA molar ratio of 1:3 and 178 m2 g−1 for M:CA molar ratio of 1:5 were produced, with H 2 evolution rates of 543 μmol h−1 g−1 and 740 μmol h−1 g−1 respectively, which were an increase of 4 and 5-fold, respectively, in comparison to the pristine sample. The enhanced efficiency of hydrogen production through photocatalysis by nanotubes, when contrasted with pristine material, can be ascribed to their high crystallinity, superior specific surface areas, decreased recombination rates of electron-hole pairs generated during light exposure, and improved dynamics of charge carriers. This hybrid technique provides a new pathway for cost-effective fabrication of g-C 3 N 4 nanotubes with substantial surface areas and high yield photocatalysts on an industrial scale, without the use of templates and hydrothermal processes for efficient hydrogen generation. [Display omitted] • Graphitic carbon nitride (g-C 3 N 4) nanotubes were synthesized using a novel hybrid synthesis technique involving dual precursor mixing. • High specific surface area g-C 3 N 4 nanotubes of ∼206 m2 g−1 and 178 m2 g−1 were achieved. • A g-C 3 N 4 nanotube with a 1:3 melamine-cyanuric acid molar ratio achieved enhanced H 2 evolution performance (740 µmol h⁻¹ g⁻¹). • The stability of g-C 3 N 4 nanotubes was shown by the consistent H 2 evolution rate during extended irradiation. [ABSTRACT FROM AUTHOR]

Tantalum oxynitride (TaON) has recently attracted much attention due to its excellent performance as a semiconductor. However, its shortage in separation of photogenerated charges hinders the wide application, which, fortunately, can be made up by forming heterojunctions with other photocatalysts. In this study, the rational design of an inorganic‐organic TaON/potassium poly (heptazine imide) (KPHI) heterojunction is reported to separate the photo charges on the two sides of this dyadic structure. The incorporation of 20 wt.% TaON into KPHI resulted not only in H2 generation but also in a wider set of environmental remediation applications under visible light, including Cr(VI) reduction and degradation of otherwise resilient antibiotics. 20TaON/KPHI effectively reduced 17.5 ppm Cr(VI) solution in 35 min under low‐power blue light irradiation with a rate constant which is ≈6 and 30 times higher than that of pristine KPHI and TaON, respectively. Moreover, the composite demonstrated a 2‐ and 40‐fold increase in H2 evolution rate in comparison to pure KPHI and TaON, respectively. This remarkable enhancement in photocatalytic activity is ascribed to the efficient electron‐hole separation and formation of an effective Z‐scheme heterojunction. This work offers a new paradigm for designing efficient photocatalytic systems for environmental applications under low‐power LED and natural sunlight. [ABSTRACT FROM AUTHOR]

The B, N co-doped carbon matrix loaded with ultra-small Ru nanoparticles (Ru/BNC) is an excellent bifunctional catalyst capable of efficiently catalyzing ammonia borane hydrolysis and alkaline water electrolysis for hydrogen evolution. [Display omitted] Developing a straightforward and general strategy to regulate the surface microenvironment of a carbon matrix enriched with N/B motifs for efficient atomic utilization and electronic state of metal sites in bifunctional hydrogen production via ammonia-borane hydrolysis (ABH) and water electrolysis is a persistent challenge. Herein, we present a simple, green, and universal approach to fabricate B/N co-doped porous carbons using ammonia-borane (AB) as a triple functional agent, eliminating the need for hazardous and explosive functional agents and complicated procedures. The pyrolysis of AB induces the regulation of the surface microenvironment of the carbon matrix, leading to the formation of abundant surface functional groups, defects, and pore structures. This regulation enhances the efficiency of atom utilization and the electronic state of the active component, resulting in improved bifunctional hydrogen evolution. Among the catalysts, B/N co-doped vulcan carbon (Ru/BNC) with 2.1 wt% Ru loading demonstrates the highest performance in catalytic hydrogen production from ABH, achieving an ultrahigh turnover frequency of 1854 min−1 (depending on the dispersion of Ru). Furthermore, this catalyst shows remarkable electrochemical activity for hydrogen evolution in alkaline water electrolysis with a low overpotential of 31 mV at 10 mA cm−2. The present study provides a simple, green, and universal method to regulate the surface microenvironment of various carbons with B/N modulators, thereby adjusting the atomic utilization and electronic state of active metals for enhanced bifunctional hydrogen evolution. [ABSTRACT FROM AUTHOR]

Co‐catalysts are commonly employed as catalytic centers to activate reactants and intermediates for driving redox reactions with photogenerated carriers during photocatalysis. Herein, a group of electronically inverted perovskite‐type nitrides CuxIn1−xNNi3 (0 ≤ x ≤ 1) are reported as novel and versatile co‐catalysts for the significantly enhanced photocatalytic hydrogen production performance on various photocatalysts, such as metal sulfides (CdS, ZnIn2S4), carbon nitride (g‐C3N4), and metal oxide (TiO2), respectively. The hybrid photocatalyst Cu0.5In0.5NNi3/CdS exhibits an optimal activity up to 6945 µmol g−1 h−1 and a remarkable enhancement factor of 6146% compared with that of pristine CdS. Besides, a high reaction stability with repetitive photocatalytic cycles is achieved. The obvious improvement of activity can be ascribed to the promoted charge separation of energetic carriers due to the metallic properties of CuxIn1−xNNi3 and abundant Ni active sites. A near‐zero Gibbs free energy of adsorbed atomic hydrogen on the Ni‐site is thermodynamically favorable for hydrogen evolution, which can be regulated by electronic states of A‐sites (Cu/In). This work not only demonstrates the great potential of perovskite‐structured nitrides as a universal platform for enhanced photocatalysis but also addresses the importance of exploring new catalytic applications for unique perovskite‐derivatives with cations/anions exchanged in coordinated sites of polyhedral. [ABSTRACT FROM AUTHOR]

Herein, carbon nitride (MCN) samples were first prepared by the molten salt method, and then Fe-doped carbon nitride (MCN) was prepared by a two-step method of calcination and hydrothermal heating and used as a novel photocatalyst for the photodegradation of seawater for the generation of H 2 or O 2 and as a sacrificial agent when glucosamine hydrochloride is present. As a result, Fe species existed in the form of Fe3+/Fe2+ in the carbon nitride flakes, which reduced the bandgap width of modified molten-salt MCN and improved the photocatalytic performance. Compared with pure MCN prepared by the molten salt method, Fe-doped MCN has superior photocatalytic ability. The best photocatalytic performance was obtained over 0.5Fe-MCN composites. Photolysis of seawater under sunlight produced 1.41 mmol h−1g−1 H 2 and 0.12 mmol h−1g−1 O 2 , which is 5.54 and 7.6 times higher than BCN, respectively. In addition, glucosamine hydrochloride as a sacrificial agent can be completely decomposed while producing 15.84 μmol h−1g−1 H 2. This study provides a new research direction for photolysis of seawater for hydrogen and oxygen production. [Display omitted] • 0.5Fe-MCN catalyst demonstrates 5.54 and 7.6-fold increased activity for hydrogen and oxygen evolution, respectively. • 0.5Fe-MCN photocatalyst could completely remove glucosamine hydrochloride to produce 15.84 μmol g−1 H 2 per hour. • Fe doping MCN could enhance the optical properties by exciting n.→ π* electronic transition. [ABSTRACT FROM AUTHOR]

Photocatalytic water splitting for hydrogen production represents a crucial approach for obtaining green energy through artificial solar energy utilization, offering a sustainable method for energy generation that helps mitigate energy shortages and protect the environment. Among the numerous photocatalytic materials, covalent organic frameworks (COFs) have garnered significant attention and intensive study from researchers due to their distinctive benefits, such as porosity, pre‐design capability, and tunability at the atomic level. Significant advancements are made in the development of materials, enhancement of performance, and comprehension of mechanisms. In this review, recent advancements in COF‐based photocatalytic water splitting are spotlighted, both in half‐reactions and overall reactions, with a particular emphasis on the rational design of COF structures to regulate the materials' optical and electrical properties, as well as the fundamental processes of photocatalysis. Drawing from current research in this field, the existing challenges, and potential opportunities are also discussed for future development. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) attract significant attention due to their ordered, crystalline, porous, metal‐free, and predictable structures. These unique characteristics offer great opportunities for the diffusion and transmission of photogenerated charges during photocatalysis. Currently, a considerable number of COFs are used as metal‐free organic semiconductor photocatalysts. This review aims to understand the relationships between the structure and photocatalysis performance of COFs and provides in‐depth insight into the synthetic strategy to improve photocatalysis performance. Subsequently, the review focuses on the structural motif of COFs in sustainable photocatalytic hydrogen evolution, carbon dioxide reduction, hydrogen peroxide generation, and organic compound transformations. Last, in conjunction with the significant progress achieved and the challenges yet to be overcome, a candid discussion is undertaken regarding the challenges and opportunities in the field of COF photocatalysis, accompanied by the presentation of potential research avenues and future directions. This review seeks to provide readers with a comprehensive understanding of the pivotal role of COFs in the field of photocatalysis, to offer robust guidance for the innovative utilization of COFs in future sustainable photocatalysis. [ABSTRACT FROM AUTHOR]

Hydrogen gas and its production from renewable power sources will be an important part of decreasing global reliance on fossil fuels and developing a sustainable energy economy. Efficient electrocatalysis, however, relies on the delivery of both protons and electrons; ideally in a concerted fashion to avoid high energy intermediates, prevent charge build‐up, and circumvent large kinetic barriers. While this can be achieved using ligand design in homogenous molecular transition metal catalysts (specifically incorporating proton shuttles in the secondary coordination sphere), heterogeneous systems are more desirable from an industrial perspective due to their ease of use and enhanced durability. Supporting transition metal catalysts on electrode surfaces is therefore a promising approach for developing next generation electrocatalysts that retain molecular level control in interfacial environments. This review will first cover key design principles from natural systems, such as hydrogenase enzymes, and then survey some representative examples of synthetic homogeneous hydrogen evolution electrocatalysts that incorporate these important features. We will then discuss transition metal species that have been supported on electrode materials, with a focus on recent advances in the field, and the major challenges that remain. [ABSTRACT FROM AUTHOR]

Graphite phase carbon nitride (g−C3N4) is a highly promising metal‐free photocatalyst, but its low activity, due to limited quantum efficiency and small specific surface area, restricts its practical application. While exfoliating bulk crystals into porous thin‐layer nanosheets and incorporating dopants have been shown to improve photocatalytic efficiency, these methods are typically complex, time‐consuming, and costly processes. In this study, we developed a simple approach to synthesize oxygen‐doped porous g−C3N4 (OCN) nanosheets. The resulting OCN exhibited significantly enhanced light absorption and visible‐light photocatalytic activity compared to bulk g−C3N4 (BCN) and g−C3N4 (CN). The OCN achieved an impressive hydrogen evolution reaction (HER) rate of 8.02 mmol g−1 h−1, eight times greater than BCN, and demonstrated a high Rhodamine B (RhB) degradation rate of 97.3 % owing to the generation of abundant singlet oxygen. These improvements in photocatalytic performance are attributed to the narrow band gap and enhanced electron transfer properties, suggesting a promising route for the efficient design of g−C3N4‐based photocatalysts. [ABSTRACT FROM AUTHOR]

Unraveling the mechanism driven by electronegativity‐dominated electronic configuration is crucial for developing high‐entropy alloys as efficient catalyst for hydrogen evolution reaction (HER). In this work, different atoms with diverse electronegativities are explored to regulate the electrocatalytic activity of PtFeCoNi@HCS toward HER, resulting in PtFeCoNiCuCr@HCS with an overpotential of 29 mV at 10 mA cm−2 and enhanced durability surpassing that of commercial 20% Pt/C in KOH environment. Based on various physicochemical and electrochemical techniques as well as density functional theory calculations, a multi‐site synergistic effect within PtFeCoNiCuCr@HCS material is elucidated in terms of both structural composition and electrocatalytic process. Briefly, Pt and Cu serve as the fundamental elements to form face‐centered cubic crystal framework, Cr primarily functions as an electron donor to regulate the electronic configuration, Co serves as the main active site for water dissociation, and the produced hydrogen species prefer to transfer toward Pt, Fe, and Cu sites for hydrogen formation. This work offers an in‐depth insight on the synergistic mechanism in high entropy alloys and is helpful for designing efficient electrocatalysts. [ABSTRACT FROM AUTHOR]

Despite challenges still remain, simultaneous regulation of light absorption, carrier separation and efficient exposed active sites of carbon nitride for the photocatalytic production of hydrogen (H 2) are essential to help alleviate the energy crisis and achieve carbon neutrality. Using in-plane phenyl groups doping and interlayer sulfate groups modification, we demonstrated an eco-friendly and facile method for excogitating porous tubular graphitic carbon nitride (PhSO-TCN2.5). The PhSO-TCN2.5 has hollow tubular morphology with ultrathin pore walls, which offers more exposed active sites, shortened charge diffusion path and readily available diffusion channels. More importantly, the in-plane phenyl groups doping and interlayer sulfate groups modification enabled significant intense the visible light absorption, accelerated carrier transfer due to the electron transport channel between the interlayers. Meanwhile, PhSO-TCN2.5 possesses exceptionally adjusted band gap structure and more negative conduction band potential. Accordingly, the above synergistic effects contribute to the efficient photocatalytic efficiency in H 2 evolution to 8709.29 μmol g−1 h−1. In addition to the apparent quantum yield of 12.0% at 420 nm, that far exceeds the reported tubular and functional group-modified carbon nitride photocatalysts. This document offers guidance on designing and producing photocatalysts with high efficiency. [Display omitted] • g-C 3 N 4 with phenyl groups doping and sulfate groups modification is fabricated. • Intercalated sulfate groups facilitate the transfer and separation of charge carriers. • The tubular structure and phenyl groups contribute to improve the light absorption. • The photocatalytic H 2 evolution of PhSO-TCN2.5 is 8709.29 μmol h−1 g−1 and AQY is 12 %. • A possible photocatalytic mechanism is proposed. [ABSTRACT FROM AUTHOR]

Replacing the sluggish oxygen evolution reaction with the oxidation of benzyl alcohol to construct the hybrid water electrolysis system has been attractive for its merits of environmentally friendly and economically efficient. However, the activity of the catalyst to oxidize alcohols needs to be further improved. Tailoring the d-band center (E d) has been proven as an effective method to promote the hydrogen evolution reaction (HER). How feasible is this strategy in the oxidation of benzyl alcohol? Here, using Co 2 C as a research platform, the doping nonmetal heteroatom (P, S, N) engineering is adopted to promote its electrocatalytic BA oxidation and HER performance. The results of electrochemical tests show that the P-doped Co 2 C (P–Co 2 C) only requires a low potential of 1.33 and 1.38 V vs. RHE to achieve current densities of 20 and 100 mA cm−2 for BA oxidation, which is superior to that of S–Co 2 C, N–Co 2 C, and pristine Co 2 C. The conversation and faradaic efficiency for BA is up to 98.1% and 93.8% during ten consecutive cycle tests. The P–Co 2 C also exhibited outstanding activity and stability toward HER. The density functional theory (DFT) calculation revealed that specified P doping could modify the d-band center of Co 2 C approaching the peak of the volcano map (electrochemical overpotentials ∼ E d). The Gibbs free energy of the BA oxidation was also reduced, thus optimizing the adsorption and desorption process of intermediates. On the other hand, the catalyst surface physical properties of Co 2 C such as hydrophilicity was promoted by the doped heteroatoms which was favorable for the gas-liquid-solid triphase electrocatalytic reaction. This work offers a facial perception of regulating the d-band to design advanced bifunctional electrocatalysts for organic matter oxidation and HER. The d-band center engineering was employed to boost the bifunctional electrocatalytic performance of X–Co 2 C (X = P, S, N). [Display omitted] • The X-doped Co 2 C (X = P, S, N) electrocatalysts were designed for BA oxidation and HER. • Among the prepared samples, the P–Co 2 C exhibited superior hydrophilicity and catalytic performance. • The P doping could change the d-band center of Co 2 C and optimize the adsorption/desorption process of intermediates. • The Gibbs free energy derived from the DFT was consistent with the order of electrochemical activity. [ABSTRACT FROM AUTHOR]

An advance of highly efficient nanostructured electrocatalysts based on non-noble metals for water electrolysis and urea oxidation reaction (UOR) are of great significance for urea-enriched wastewater remediation and producing hydrogen. Herein, we report V x Ni 1-x O catalysts supported on three-dimensional Ni-foam scaffold for catalytic water and urea electrolysis. V x Ni 1-x O catalysts show rapid water and urea electrolysis due to enhanced electrochemical surface area (ECSA). Most important of all, the urea oxidation reaction has a lower potential of 1.418V vs RHE as compared to oxygen evolution reaction (1.684 V vs RHE) system to generate 100 mA/cm2. Additionally, a two-electrode cell for bi-functional water electrolysis generates 100 mA/cm2 at a potential of 2.10 V at 20 °C and just 1.86 V at 60 °C temperature due to regulated the adsorption/desorption of intermediates species, enhanced charge and mass transport, and easier desorption of oxygen molecules from the anode. The stability of V x Ni 1-x O catalyst was measured at 1000 mA/cm2 current density for up to 17 h. • Doping energy strategy to design a vertical V x Ni 1-x O nanosheets for water and urea electrolysis. • Overpotential of 454 mV for OER and 271 mV for HER at 100 mA/cm2. • Maximum current of 1000 mA/cm2 is achieved at a cell potential of 2.3 V. • V 0.1 Ni 0.9 O catalyst shows he stability for 17 h at 1000 mA/cm2. • Urea electrolysis system has a lower cell potential of 1.418V at 100 mA/cm2. [ABSTRACT FROM AUTHOR]

The photocatalytic activity of 2D/2D/0D heterostructures based on few-layer black phosphorus (FLBP) g-C3N4/FLBP/Co2P in the reaction of photocatalytic hydrogen formation from an aqueous solution of triethanolamine under under visible light irradiation (400 nm) was studied for the first time. An original method for the preparation of the g‑C3N4/FLBP/Co2P composite photocatalyst is proposed, which consists of the solvothermal synthesis of cobalt phosphide Co2P nanoparticles, their immobilization on the surface of FLBP, and subsequent mixing of the FLBP/Co2P heterostructure with g‑C3N4. The synthesized photocatalysts were characterized by physicochemical analytical methods (X-ray diffraction, X-ray photoelectron spectroscopy, high-resolution transmission microscopy, energy-dispersive X-ray spectroscopy). The hydrogen evolution rate in the presence of the g‑C3N4/FLBP/Co2P heterostructure was 0.09 mmol h–1, which is 25 times higher than the same characteristic for the unmodified g‑C3N4 sample. The obtained numerical values of the photocatalytic activity are at the level of the literature values. [ABSTRACT FROM AUTHOR]

The photocatalytic decomposition of ammonia to produce N2 and H2 was achieved using single-walled carbon nanotube (SWCNT) nanohybrids. The physical modification of ferrocene-dye-encapsulated CNTs by amphiphilic C60-dendron yielded nanohybrids with a dye/CNT/C60 coaxial heterojunction. Upon irradiation with visible light, an aqueous solution of NH3 and dye@CNT/C60-dendron nanohybrids produced both N2 and H2 in a stoichiometric ratio of 1/3. The action spectra of this reaction clearly demonstrated that the encapsulated dye acted as the photosensitizer, exhibiting an apparent quantum yield (AQY) of 0.22% at 510 nm (the λmax of the dye). This study reports the first example of dye-sensitized ammonia decomposition and provides a new avenue for developing efficient and sustainable photocatalytic hydrogen production systems. [ABSTRACT FROM AUTHOR]

Developing photocatalysts with desired activity and stability toward hydrogen evolution reaction (HER) in alkaline seawater is of prime significance but still pressingly challenging. Herein, cuprum nanoclusters (CuNCs) are anchored on the surface of cadmium sulphide homojunctions (CdS‐H) with unsaturated edge sulphur (S) by an in situ photoreduction technique, which promotes the stability and hydrogen evolution of photocatalyst in the process of alkaline seawater hydrogen (H2) evolution (15.5 mmol g−1 h−1) with an apparent quantum yield of 11.0% at 450.0 nm. It is comprehensively confirmed that the unsaturated edge S not only effectively anchored Cu NCs but also promoted the adsorption of chloride ion (Cl−) ions, which suppressed the oxidation of lattice S and modulated the stability of the photocatalyst in alkaline seawater. The photothermal effect induced by the anchored Cu NCs accelerated the reaction kinetics, and the directional migration of the photocarrier at the metal‐semiconductor interface is demonstrated via the in situ method. This work affords a new perspective to rational design photocatalysts with high stability and superior performance in alkaline seawater. [ABSTRACT FROM AUTHOR]

The electrochemical removal of abundant and toxic H2S from highly sour reservoirs has emerged as a promising method for hydrogen production and desulfurization. Nevertheless, the ineffectiveness and instability of current electrocatalysts have impeded further utilization of H2S. In this communication, we introduce a robust array of Fe2NiSe4 nanowires synthesized in situ on a FeNi3 foam (Fe2NiSe4/FeNi3) via hydrothermal treatment. This array acts as an active electrocatalyst for ambient H2S splitting. It offers numerous exposed active sites and a rapid electron transport channel, significantly enhancing charge transport rates. As an electrode material, Fe2NiSe4/FeNi3 displays remarkable electrocatalytic efficiency for both sulfide oxidation and hydrogen evolution reactions. This bifunctional electrode achieves efficient electrochemical H2S splitting at a low potential of 440 mV to reach a current density of 100 mA∙cm−2, with a faradaic efficiency for hydrogen production of approximately 98%. These findings highlight its significant potential for desulfurization and energy-efficient hydrogen generation. [ABSTRACT FROM AUTHOR]

The catalytic activity of FeCo alloy nanoparticles (NPs) supported on nitrogen-doped mesoporous carbon spheres (FeCo/NMCS) was evaluated for hydrogen evolution and reduction of various organic dyes. The NMCS was spherical, with an average diameter of 488.1 nm, while the FeCo alloy NPs were evenly distributed across the NMCS, with an average diameter of 8.2 nm. The nitrogen content in FeCo/NMCS was found to be 3.91 wt%. The FeCo/NMCS displayed remarkable efficiency in hydrogen evolution through the hydrolysis of ammonia borane (AB), characterized by an activation energy of 23.49 kJ/mol. The FeCo/NMCS also demonstrated superior catalytic activity in reducing 4-nitrophenol (4-NP), with a reduction rate constant of 0.468 min⁻1 using 5 mg of FeCo/NMCS and 20 mg of AB. This rate places the FeCo/NMCS among the highest-performing catalysts for 4-NP reduction. Further, the catalyst efficiently reduced crystal violet, methylene blue, and rhodamine B under the same conditions. Azo dyes, including tartrazine, methyl orange, Red 195, and Yellow 145, underwent faster reduction than other tested dyes. The FeCo/NMCS maintained its integrity and activity even after four hydrogen generation cycles. These results highlight FeCo/NMCS's potential as a multifunctional, magnetically separable, and reusable catalyst for efficient hydrogen production and environmental remediation applications. [ABSTRACT FROM AUTHOR]

Modulating lattice strain in intermetallic compounds could effectively alter their electronic structure and binding energy, thus impacting catalytic activity. Strain is usually induced through lattice mismatch, achieved by constructing core‐shell nanostructures or metal‐substrate interfaces with complex reciprocity and distractors. However, in situ induced strain without interface‐construction or lattice mismatch presents challenges. In this study, we precisely manipulate consecutive compressive strain from −0.5% to −0.8% in CoPt3Pd intermetallic compound by inducing interior atomic radius mismatch. Precise strain control results in a negative shift of d‐band center, dynamic charge distribution, and facilitates water dissociation, leading to enhanced electrocatalytic activity. The CoPt3Pd catalyst with −0.5% compressive strain exhibits exceptional hydrogen evolution activity, with an overpotential of 169 mV at 1 A cm−2. Our approach offers a straightforward method to manipulate compressive strain on intermetallic compounds by atomic size mismatch, with broad implications for catalytic processes. [ABSTRACT FROM AUTHOR]

Controlling the electronic structure based on the valence state is key for effective electrocatalysis, and the challenge lies in attaining the optimal metal valence states. Here, a new approach called valence‐elastic control is introduced to create intermediate‐valence Ru species within a‐RuOx/C catalyst matrices. By utilizing hetero‐interfaces between RuOx and C, pathways for efficient electron transfer and precise valence adjustment are activated through switchable bonding at the interfaces. The catalyst demonstrates exceptional performance in hydrogen evolution reaction with an unprecedentedly low overpotential of 4.1 mV in KOH + seawater electrolytes at 10 mA cm−2. Furthermore, the two‐electrode electrolyzer demonstrates improved stability and voltage efficiency compared to the commercial Pt/C‐based system. The in situ tests combined with theoretical analysis reveal the water dissociation and *H adsorption are optimized by the switchable interface bonding of the tailored Ru species. This study showcases a transformative design framework for next‐generation high‐efficiency metal catalysts with variable valence. [ABSTRACT FROM AUTHOR]

The development of electrodes for hydrogen evolution via water splitting in a neutral electrolyte is highly desirable, especially considering that natural water resources such as seawater typically have a neutral pH. In this study, silicon nanowires (SiNWs) arrays with uniform silver (Ag) decoration are prepared as a cathode material, which exhibits excellent and stable electrochemical performance for neutral water electrolysis. Ag ions, utilized in the preparation of SiNWs through metal-assisted chemical etching technique, are retained and decorated within the SiNWs array without undergoing a dissolution process, referred to as Native SiNWs. Remained Ag+ ions on the SiNWs are activated photocathodically and reduced to Ag0, resulting in a significantly enhanced performance as an electrocatalyst for hydrogen evolution reaction (HER). Hence, this photocathodic activation of Native SiNWs (PCA-Native SiNWs) eliminates the need for additional cocatalyst deposition for HER, utilizing the Ag ions employed in the SiNWs preparation process. This enhancement in HER activity is exclusively observed by photocathodic activation, not by cathodic activation without light irradiation, indicating the crucial role of photoelectrons in SiNWs under light irradiation for the activation. Additionally, the nanowire structure serves as an ideal platform for Ag nanoparticles, providing sufficient surface area, resulting in excellent dispersion and an increased number of active sites. Furthermore, PCA-Native SiNWs demonstrates outstanding electrochemical stability for over 60 h, with no significant reduction in current density or structural degradation in a neutral electrolyte. Several characterizations and electrochemical analyses have been conducted to elucidate the in-situ decoration of Ag nanoparticles on SiNWs and investigate the surface chemistry for the activation mechanism. This work introduces a new perspective on using Ag-decorated SiNWs directly as an electrocatalyst for effective hydrogen evolution in a neutral media. Saleem et al., "A Strategy to Reutilize Silver Nanoparticles on Silicon Nanowires via Photocathodic Activation for Enhanced and Sustainable Hydrogen Evolution"Native SiNWs, which are prepared by retaining Ag nanoparticles during SiNW synthesis, exhibited better performance for HER than SiNWs. Additionally, the retained Ag can be more evenly distributed and reduced during photocathodic activation, resulting in significantly improved HER activity. [Display omitted] • Photocathodically activated Native SiNWs (PCA-Native SiNWs) are developed. • Retained Ag ions on SiNWs are reduced and activated by light irradiation and cathodic potential (photocathodic activation). • Reduced Ag enhances electrochemical performance of SiNWs as an electrocatalyst. • Ag nanoparticles are evenly distributed vis the dissolution-redeposition phenomenon. • PCA-Native SiNWs show stable activity in neutral pH. [ABSTRACT FROM AUTHOR]

Solar-driven water splitting for hydrogen production is a vital approach to mitigating the energy crisis and achieving carbon neutrality and peak carbon emissions. Cd 0.8 Mn 0.2 S holds significant potential for photocatalytic hydrogen evolution but faces severe challenges due to photogenerated carrier recombination. To address this, we employed ultrasonic self-assembly to tightly couple Cu 2 WS 4 nanosheets with Cd 0.8 Mn 0.2 S nanoparticles, forming an S-scheme heterojunction to reduce carrier recombination rates. In this configuration, Cd 0.8 Mn 0.2 S acts as the electron acceptor, and Cu 2 WS 4 serves as the electron donor. The Cd 0.8 Mn 0.2 S/Cu 2 WS 4 structure creates a closely spaced interface, providing the shortest transfer distance for electron migration. The S-scheme heterojunction strategy effectively suppresses the recombination of photogenerated carriers, promoting vectorial separation. Under 10 W white light irradiation, the Cd 0.8 Mn 0.2 S/Cu 2 WS 4 composite photocatalyst exhibited remarkable hydrogen evolution activity, with a hydrogen production rate of 39.83 mmol g−1 h−1. This S-scheme heterojunction strategy lays the foundation for the structural design and large-scale application of high-activity visible-light photocatalysts. • Recombination of photogenerated carriers is inhibited. • Facilitated vector separation of photogenerated carriers. • In situ irradiated XPS validates the S-scheme heterojunction charge transfer mechanism. [ABSTRACT FROM AUTHOR]

In this study, we present self-supported vanadium-doped copper sulfide (Cu 2 S) electrodes as effective catalytic network for alkaline water electrolysis. The electrodes demonstrate a remarkably lower value of overpotential 375 mV for HER (hydrogen evolution reaction) and 403 mV for OER (oxygen evolution reaction) to generate 100 mA/cm2 current. A bi-functional electrolyzer incorporating these electrodes achieves a high current of 100 mA/cm2 at a cell voltage of 1.97 V. The positive influence of vanadium incorporation enhances the overall electrocatalytic activity of Cu 2 S and capable of generating the geometric current density of more than 500 mA/cm2 current for bi-functional electrolysis in industrial-scale alkaline electrolyte 5 M KOH at an elevated temperature of 60 °C, highlighting its potential for practical applications in renewable hydrogen production. Furthermore, the stability of electrodes was measured at different current densities at 20, 50 and 300 mA/cm2, suggesting the capabilities of electrodes for sustainable water electrolysis for green H 2 and O 2 production. DFT analyses confirms that the V-Cu s S exhibits superior performance owing to favourable H-adsorption energy on S-sites and minimum Gibb's free energy on V-sites. The study focuses on specific electrochemical performance metrics, offering insights into the promising utilization of vanadium-doped Cu 2 S electrodes for efficient water splitting in alkaline environments. [Display omitted] • Self-supported catalysts V–Cu 2 S were synthesized by hydrothermal technique. • Electrolyser generates 100 mA/cm2 current at 1.97 V in an alkaline solution. • Industrial scale water electrolysis is achieved with current of 500 mA/cm2. • DFT study shows superior HER on V–Cu 2 S due to favourable H-adsorption on S-sites. • Optimal Δ G H of 0.54 eV on V-sites in V–Cu 2 S accelerates catalytic activity. [ABSTRACT FROM AUTHOR]

A one-step calcination method was employed to fabricate a new TiO 2 /g-C 3 N 4 (TCN) composite catalyst. The therein TiO 2 nanoparticles with good dispersion were synthesized through a sol-gel method and followed by additional heat treatment. The ultra-thin and flat g-C 3 N 4 (CN) nanosheets were synthesized by calcining a mixture of urea and melamine. The obtained TCN exhibited significantly excellent performance, especially when 3 wt% Pt was added and lactic acid (HL) was used as a sacrificial agent, achieving a rate of 32.5 mmol/h/g. This improvement can be attributed to the uniform dispersion of nano TiO 2 particles on g-C 3 N 4 , the flat ultra-thin layer structure of CN, and the constructed heterojunctions between two, which promote the separation of photogenerated electron-hole pairs. Measurements of PL and photocurrent response confirmed enhanced efficiency in interface charge separation and transfer. Additionally, it demonstrated lower internal resistance in EIS tests. Notably, owing to the piezoelectric properties of CN, when the reaction liquid was subjected to additional ultrasonic treatment, the hydrogen production rate further increased to 43.57 mmol/h/g and 2.9 mmol/h/g, respectively, in simulated sunlight and visible light response. The piezoelectric effect of CN induced by ultrasound regulated the bandgap width of the catalysts, broadening their response to visible light. [Display omitted] • Small TiO 2 nanoclusters with good dispersion combined with ultra-thin, flat g-C 3 N 4. • The obtained TiO 2 /g-C 3 N 4 exhibited boosting photocatalytic hydrogen. • H 2 yield rate is 33 mmol/h/g with lactic acid sacrificial agent and Pt-deposition. • Hydrogen yield rate raised to 43.57 mmol/h/g due to piezoelectric effect of C 3 N 4. • Piezoelectric effect caused by ultrasound affected the response to visible light. [ABSTRACT FROM AUTHOR]

Highlights: Bimetallic single-atom catalysts (bimSACs) have garnered significant attention for leveraging the synergistic functions of the two metal active centers. This review focuses on the advancements in the field of bimSACs and their pivotal role in hydrogen generation via water splitting. State-of-the-art computational and physicochemical techniques for the analysis of bimSACs and their application in electrocatalytic water splitting are discussed. Green hydrogen from water splitting has emerged as a critical energy vector with the potential to spearhead the global transition to a fossil fuel-independent society. The field of catalysis has been revolutionized by single-atom catalysts (SACs), which exhibit unique and intricate interactions between atomically dispersed metal atoms and their supports. Recently, bimetallic SACs (bimSACs) have garnered significant attention for leveraging the synergistic functions of two metal ions coordinated on appropriately designed supports. BimSACs offer an avenue for rich metal–metal and metal–support cooperativity, potentially addressing current limitations of SACs in effectively furnishing transformations which involve synchronous proton–electron exchanges, substrate activation with reversible redox cycles, simultaneous multi-electron transfer, regulation of spin states, tuning of electronic properties, and cyclic transition states with low activation energies. This review aims to encapsulate the growing advancements in bimSACs, with an emphasis on their pivotal role in hydrogen generation via water splitting. We subsequently delve into advanced experimental methodologies for the elaborate characterization of SACs, elucidate their electronic properties, and discuss their local coordination environment. Overall, we present comprehensive discussion on the deployment of bimSACs in both hydrogen evolution reaction and oxygen evolution reaction, the two half-reactions of the water electrolysis process. [ABSTRACT FROM AUTHOR]

Although MoS2 quantum dots with abundant edge sites have been regarded as promising eletrode materials for the hydrogen evolution reaction (HER), their electrocatalytic capacity still requires improvements in actual applications. Herein. we demonstrate a controllable and robust bottom‐up approach to build 3D crosslinked graphene‐Ti3C2Tx MXene frameworks decorated with MoS2 quantum dots (MQD/RGO‐MX) via a convenient co‐assembly process. The novel structural design gives the MQD/RGO‐MX nanoarchitectures a series of superior textural attributes, including 3D interconnected networks, continuous meso‐ and macropores, well‐dispersed quantum dots, ameliorative electronic configuration, and excellent electrical conductivity. Accordingly, the resulting hybrid nanoarchitectures express superior electrocatalytic properties in terms of a low onset potential of only 45 mV, a small Tafel slope of 61 mV dec−1 as well as a long service life towards the HER, which make it quite competitive against bare MoS2 quantum dots, MXene as well as binary MQD/RGO and MQD/MXene electrocatalysts. [ABSTRACT FROM AUTHOR]