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Solar-to-chemical energy conversion via heterogeneous photocatalysis is one of the sustainable approaches to tackle the growing environmental and energy challenges. Among various promising photocatalytic materials, plasmonic-driven photocatalysts feature prominent solar-driven surface plasmon resonance (SPR). Non-noble plasmonic metals (NNPMs)-based photocatalysts have been identified as a unique alternative to noble metal-based ones due to their advantages like earth-abundance, cost-effectiveness, and large-scale application capability. This review comprehensively summarizes the most recent advances in the synthesis, characterization, and properties of NNPMs-based photocatalysts. After introducing the fundamental principles of SPR, the attributes and functionalities of NNPMs in governing surface/interfacial photocatalytic processes are presented. Next, the utilization of NNPMs-based photocatalytic materials for the removal of pollutants, water splitting, CO2 reduction, and organic transformations is discussed. The review concludes with current challenges and perspectives in advancing the NNPMs-based photocatalysts, which are timely and important to plasmon-based photocatalysis, a truly interdisciplinary field across materials science, chemistry, and physics. [ABSTRACT FROM AUTHOR]

As an alternative to hydrogen peroxide (H2O2) production by complex anthraquinone oxidation process, photosynthesis of H2O2 from water and oxygen without sacrificial agents is highly demanded. Herein, a covalently connected molecular heterostructure is synthesized via sequential C−H arylation and Knoevenagel polymerization reactions for visible‐light and sacrificial‐agent‐free H2O2 synthesis. The subsequent copolymerization of the electron‐deficient benzodithiophene‐4,8‐dione (BTD) and the electron‐rich biphenyl (B) and p‐phenylenediacetonitrile (CN) not only expands the π‐conjugated domain but also increases the molecular dipole moment, which largely promotes the separation and transfer of the photoinduced charge carriers. The optimal heterostructured BTDB‐CN0.2 manifested an impressive photocatalytic H2O2 production rate of 1920 μmol g−1 h−1, which is 2.2 and 11.6 times that of BTDB and BTDCN. As revealed by the femtosecond transient absorption (fs‐TA) and theoretical calculations, the linkage serves as a channel for the rapid transfer of photogenerated charge carriers, enhancing the photocatalytic efficiency. Further, in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) uncovers that the oxygen reduction reaction occurs through the step one‐electron pathway and the mutual conversion between C=O and C−OH with the anchoring of H+ during the catalysis favored the formation of H2O2. This work provides a novel perspective for the design of efficient organic photocatalysts. [ABSTRACT FROM AUTHOR]

As an alternative to hydrogen peroxide (H2O2) production by complex anthraquinone oxidation process, photosynthesis of H2O2 from water and oxygen without sacrificial agents is highly demanded. Herein, a covalently connected molecular heterostructure is synthesized via sequential C−H arylation and Knoevenagel polymerization reactions for visible‐light and sacrificial‐agent‐free H2O2 synthesis. The subsequent copolymerization of the electron‐deficient benzodithiophene‐4,8‐dione (BTD) and the electron‐rich biphenyl (B) and p‐phenylenediacetonitrile (CN) not only expands the π‐conjugated domain but also increases the molecular dipole moment, which largely promotes the separation and transfer of the photoinduced charge carriers. The optimal heterostructured BTDB‐CN0.2 manifested an impressive photocatalytic H2O2 production rate of 1920 μmol g−1 h−1, which is 2.2 and 11.6 times that of BTDB and BTDCN. As revealed by the femtosecond transient absorption (fs‐TA) and theoretical calculations, the linkage serves as a channel for the rapid transfer of photogenerated charge carriers, enhancing the photocatalytic efficiency. Further, in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) uncovers that the oxygen reduction reaction occurs through the step one‐electron pathway and the mutual conversion between C=O and C−OH with the anchoring of H+ during the catalysis favored the formation of H2O2. This work provides a novel perspective for the design of efficient organic photocatalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • Facile synthesis of anode material with organized structure. • Binary composite demonstrates better performance than its unitary counterpart. • In-situ XRD together with in-depth characterization reveals sodium ion storage. • DFT calculation verifies the sodium migration barrier. Sodium-ion batteries offer significant advantages in terms of low-temperature performance and safety. In this study, we present a straightforward synthetic approach to produce bimetallic selenide NiCoSe 2 nanoparticles grown on a three-dimensional porous carbon framework for application as anode materials in sodium-ion batteries. This unique architecture enhances reaction kinetics and structural stability. The three-dimensional interconnected porous carbon network establishes a continuous pathway of electronic conductive, while increasing specific surface area and mitigating volume expansion. Consequently, these features expedite ion transfer and enhance electrolyte interaction. Notably, compared to CoSe, NiCoSe 2 exhibits reduced ion transport distances and lower sodium diffusion barriers. Leveraging these attributes, NiCoSe 2 /N, Se co-doped carbon composite materials (NiCoSe 2 /NSC) demonstrate a high specific capacity of 320.8 mAh/g, even after 1000 cycles at 5.0 A/g, with a capacity retention rate of 85.1%. The study further delves into the revelation of the reaction mechanism and ion transport pathway through in-situ X-ray diffraction (XRD) analysis and theoretical calculations. The development of these anode materials is poised to pave the way for advancements in sodium-ion battery technology. [ABSTRACT FROM AUTHOR]

Emerging step‐scheme (S‐scheme) heterostructures hold unique superiority in steering directional charge transport and reinforcing redox capacity, yet rational modification of S‐scheme heterostructures by single atoms (SAs) for efficient photocatalytic H2 evolution is rarely reported. In this work, Pd SAs‐modulated organic–inorganic g‐C3N4/CdS S‐scheme heterostructures are designed and prepared by a one‐pot mechanochemical approach allowing for g‐C3N4 nanosheets/CdS nanoparticles to confine atomically dispersed Pd co‐catalysts. The g‐C3N4/CdS S‐scheme charge‐transfer pathway is corroborated by a combination of in situ irradiated X‐ray photoelectron spectroscopy, electron paramagnetic resonance, and Kelvin probe force microscopy. Density functional theory (DFT) calculations, high‐angle annular dark‐field scanning transmission electron microscopy, and X‐ray absorption fine structure identify Pd‐S3 and Pd‐N2 atomic moieties underpinned by the electronic interaction between Pd SAs and g‐C3N4/CdS heterostructures, in which the d‐band center of Pd SAs is optimized for proton adsorption thermodynamically. Further, the g‐C3N4/CdS S‐scheme heterostructures alongside Pd SAs in concert boost the rapid migration of photogenerated electrons (1.05 ps) via Pd─S and Pd─N bond‐derived channels. A maximal H2 evolution rate of 85.66 mmol h−1 g−1 is achieved by 1 wt% Pd‐20 wt% g‐C3N4/CdS hierarchical composites. This work may guide the design of high‐efficiency S‐scheme‐based photocatalysts for solar‐to‐H2 conversion and beyond. [ABSTRACT FROM AUTHOR]

[Display omitted] Various adsorbents for CO 2 capture have been developed to mitigate the greenhouse effect. In this work, a novel CO 2 adsorbent was fabricated by depositing triethanolamine (TEOA) onto the surface of nickel-cobalt-aluminum layered double oxide (NiCoAl-LDO) via the impregnation method. The CO 2 capacity of the TEOA-LDO composite reached 1.27 mmol/g at 0 °C and 100 kPa, which was twice that of unmodified NiCoAl-LDO. In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) showed that the hydroxyl groups (–OH) on the surface of NiCoAl-LDO played a significant role in facilitating CO 2 adsorption, similar to CO 2 adsorption in the presence of H 2 O, where CO 2 is not converted to carbamates but to bicarbonates through base-catalyzed hydration. This bicarbonate pathway doubles the theoretical amine efficiency, increases the CO 2 capacity, and reduces the energy consumption during CO 2 desorption. The work provides valuable insights into the development of CO 2 adsorbents with high capacity, excellent cycling stability, and low regeneration energy. [ABSTRACT FROM AUTHOR]

[Display omitted] • A ternary Ru 0.4 Sn 0.3 Ti 0.3 electrode was prepared via thermal decomposition processes. • Ru 0.4 Sn 0.3 Ti 0.3 electrode exhibits greatly restrained OER behavior during CER process. • Ru 0.4 Sn 0.3 Ti 0.3 electrode shows large O 2 -Cl 2 potential differences between CER and OER. • Ru 0.4 Sn 0.3 Ti 0.3 electrode shows 90 % Cl 2 selectivity at 200 mA cm−2 current density. • Modulated d -band center of Ru 3 d orbital contributes to the enhanced CER activity. Chlorine evolution reaction (CER) is a commercially valuable electrochemical reaction used at an industrial scale. However, oxygen evolution reaction (OER) during the electrolysis process inevitably leads to the decreased efficiency of CER. It is necessary to improve the selectivity of CER by minimizing or even eliminating the occurrence of OER. Herein, a ternary metal oxide (Ru 0.4 Sn 0.3 Ti 0.3) electrode was fabricated and employed as an active and robust anode for CER. The Ru 0.4 Sn 0.3 Ti 0.3 electrode exhibits an excellent CER performance in 6.0 M NaCl solution, with a low potential of 1.17 V (vs. saturated calomel electrode, SCE) at 200 mA cm−2 current density, a high Cl 2 selectivity of over 90 %, and robust durability after consecutive operation for 160 h under 100 mA cm−2. The maximum O 2 -Cl 2 potential difference between OER and CER further demonstrates the high Cl 2 selectivity of Ru 0.4 Sn 0.3 Ti 0.3 electrode. Theoretical studies show that the strong Ru 3 d −Ti 3 d orbitals hybridization effect makes the d -band center (ε d) of Ru 3 d and Ti 3 d orbitals positively and negatively shifted, respectively, endowing Ru site with enhanced Cl adsorption ability (i.e. enhanced Ru−Cl interaction) and Ru 0.4 Sn 0.3 Ti 0.3 electrode with superior CER activity. This work offers valuable insights into the development of advanced electrodes for CER in practical application. [ABSTRACT FROM AUTHOR]

[Display omitted] Compared to hydrogen production through pure water photocatalysis, the direct utilization of seawater for hydrogen production aligns better with the principles of sustainable development. Seawater, however, contains impurity ions like Na+ and Cl−, which pose higher demands on photocatalysts. It is widely acknowledged that RuO 2 and TiO 2 demonstrate excellent stability in seawater. Consequently, this study focuses on the model system of RuO 2 -modified TiO 2 for investigating hydrogen production in simulated seawater. TiO 2 /RuO 2 nanofibers (NFs) were synthesized via a one-step electrospinning method, ensuring intimate contact between the two components. The hydrogen production activity of TiO 2 /RuO 2 NFs in simulated seawater nearly matches that in pure water. Remarkably, RuO 2 serves as an oxidation cocatalyst, effectively scavenging holes from the valence band of TiO 2 and enhancing the separation efficiency of electrons and holes. Interestingly, Cl− ions, similar to RuO 2 , contribute to reducing excess holes. This study lays the groundwork for future research into hydrogen production from seawater. [ABSTRACT FROM AUTHOR]

NiMn2O4/C hollow spheres with sandwich-structured shells were fabricated by a hydrothermal method. Leveraging the mesoporous design of the carbon hollow spheres, NiMn2O4 nanosheets were evenly dispersed on both the inner and outer surfaces of the carbon shells. NiMn2O4/C demonstrated excellent rate capability and prolonged cycling durability for sodium ion storage. [ABSTRACT FROM AUTHOR]

Cooperative coupling of H2 evolution with oxidative organic synthesis is promising in avoiding the use of sacrificial agents and producing hydrogen energy with value‐added chemicals simultaneously. Nonetheless, the photocatalytic activity is obstructed by sluggish electron‐hole separation and limited redox potentials. Herein, Ni‐doped Zn0.2Cd0.8S quantum dots are chosen after screening by DFT simulation to couple with TiO2 microspheres, forming a step‐scheme heterojunction. The Ni‐doped configuration tunes the highly active S site for augmented H2 evolution, and the interfacial Ni−O bonds provide fast channels at the atomic level to lower the energy barrier for charge transfer. Also, DFT calculations reveal an enhanced built‐in electric field in the heterojunction for superior charge migration and separation. Kinetic analysis by femtosecond transient absorption spectra demonstrates that expedited charge migration with electrons first transfer to Ni2+ and then to S sites. Therefore, the designed catalyst delivers drastically elevated H2 yield (4.55 mmol g−1 h−1) and N‐benzylidenebenzylamine production rate (3.35 mmol g−1 h−1). This work provides atomic‐scale insights into the coordinated modulation of active sites and built‐in electric fields in step‐scheme heterojunction for ameliorative photocatalytic performance. [ABSTRACT FROM AUTHOR]

Cooperative coupling of H2 evolution with oxidative organic synthesis is promising in avoiding the use of sacrificial agents and producing hydrogen energy with value‐added chemicals simultaneously. Nonetheless, the photocatalytic activity is obstructed by sluggish electron‐hole separation and limited redox potentials. Herein, Ni‐doped Zn0.2Cd0.8S quantum dots are chosen after screening by DFT simulation to couple with TiO2 microspheres, forming a step‐scheme heterojunction. The Ni‐doped configuration tunes the highly active S site for augmented H2 evolution, and the interfacial Ni−O bonds provide fast channels at the atomic level to lower the energy barrier for charge transfer. Also, DFT calculations reveal an enhanced built‐in electric field in the heterojunction for superior charge migration and separation. Kinetic analysis by femtosecond transient absorption spectra demonstrates that expedited charge migration with electrons first transfer to Ni2+ and then to S sites. Therefore, the designed catalyst delivers drastically elevated H2 yield (4.55 mmol g−1 h−1) and N‐benzylidenebenzylamine production rate (3.35 mmol g−1 h−1). This work provides atomic‐scale insights into the coordinated modulation of active sites and built‐in electric fields in step‐scheme heterojunction for ameliorative photocatalytic performance. [ABSTRACT FROM AUTHOR]

Photocatalysis is considered an effective approach for converting CO2 into high‐value‐added chemicals. However, practical implementation of this technology is limited by the efficiency and stability of photocatalysis. Herein, an interfacial control strategy is proposed to optimize the homogeneous‐heterogeneous hybrid photocatalysis by enhancing the interaction between light‐harvesting semiconductors (LHS) and molecular active centers (MAC). Based on this strategy, self‐assembled organic semiconductors with controlled surface architectures are constructed using 1,6‐bis(phenylethynyl)pyrene building blocks to act as LHS. Combining with the classical MAC, an excellent CO2 photoreduction performance is achieved with a CO turnover number of > 2980 maintaining long‐term stability with a selectivity of > 90%, and an apparent quantum yield of > 2.3%. Theoretical calculations combined with in situ and transient spectroscopy studies reveal that the optimized biphase interface dominates the synergy between the homogeneous and heterogeneous photocatalysts. This strategy and the proposed mechanism of interactions will contribute to the design of future artificial photosynthesis systems. [ABSTRACT FROM AUTHOR]

The interaction between a co‐catalyst and photocatalyst usually induces spontaneous free‐electron transfer between them, but the effect and regulation of the transfer direction on the hydrogen‐adsorption energy of the active sites have not received attention. Herein, to steer the free‐electron transfer in a favorable direction for weakening S−Hads bonds of sulfur‐rich MoS2+x, an electron‐reversal strategy is proposed for the first time. The core–shell Au@MoS2+x cocatalyst was constructed on TiO2 to optimize the antibonding‐orbital occupancy. Research results reveal that the embedded Au can reverse the electron transfer to MoS2+x to generate electron‐rich S(2+δ)− active sites, thus increasing the antibonding‐orbital occupancy of S−Hads in the Au@MoS2+x cocatalyst. Consequently, the increase in the antibonding‐orbital occupancy effectively destabilizes the H 1s‐p antibonding orbital and weakens the S−Hads bond, realizing the expedited desorption of Hads to rapidly generate a lot of visible H2 bubbles. This work delves deep into the latent effect of the photocatalyst carrier on cocatalytic activity. [ABSTRACT FROM AUTHOR]

The interaction between a co‐catalyst and photocatalyst usually induces spontaneous free‐electron transfer between them, but the effect and regulation of the transfer direction on the hydrogen‐adsorption energy of the active sites have not received attention. Herein, to steer the free‐electron transfer in a favorable direction for weakening S−Hads bonds of sulfur‐rich MoS2+x, an electron‐reversal strategy is proposed for the first time. The core–shell Au@MoS2+x cocatalyst was constructed on TiO2 to optimize the antibonding‐orbital occupancy. Research results reveal that the embedded Au can reverse the electron transfer to MoS2+x to generate electron‐rich S(2+δ)− active sites, thus increasing the antibonding‐orbital occupancy of S−Hads in the Au@MoS2+x cocatalyst. Consequently, the increase in the antibonding‐orbital occupancy effectively destabilizes the H 1s‐p antibonding orbital and weakens the S−Hads bond, realizing the expedited desorption of Hads to rapidly generate a lot of visible H2 bubbles. This work delves deep into the latent effect of the photocatalyst carrier on cocatalytic activity. [ABSTRACT FROM AUTHOR]

[Display omitted] • In-situ formed N, S co-doped carbon-supported FeS nanoparticles. • The synergy between electrode and electrolyte is demonstrated. • Thick SEI film and large volume expansion are harmful to cycle life. • The sodium storage mechanism is revealed by in-situ XRD. Pyrrhotite (FeS) is extensively investigated as the anode for low-cost sodium-ion batteries (SIBs) due to their natural abundance and high theoretical capacity. However, it suffers from significant volume expansion and poor conductivity. These problems can be alleviated by promoting sodium-ion transport and introducing carbonaceous materials. Here, FeS decorated on N, S co-doped carbon (FeS/NC) is constructed through a facile and scalable strategy, which is the best of both worlds. Moreover, to give full play to the role of the optimized electrode, ether-based and ester-based electrolytes are used for matching. Reassuringly, the FeS/NC composite displays a reversible specific capacity of 387 mAh g−1 after 1000 cycles at 5A g−1 in dimethyl ether electrolyte. The even distribution of FeS nanoparticles on the ordered framework of carbon guarantees a fast electron/Na-ion transport channel, and the reaction kinetics can be further accelerated in the dimethyl ether (DME) electrolyte, ensuring the excellent rate capability and cycling performance of FeS/NC electrodes for sodium-ion storage. This finding not only provides a reference for the introduction of carbon via in-situ growth protocol, but also demonstrates the necessity for electrolyte–electrode synergy in realizing efficient sodium-ion storage. [ABSTRACT FROM AUTHOR]

The S‐scheme heterojunction is flourishing in photocatalysis because it concurrently realizes separated charge carriers and sufficient redox ability. Steady‐state charge transfer has been confirmed by other methods. However, an essential part, the transfer dynamics in S‐scheme heterojunctions, is still missing. To compensate, a series of cadmium sulfide/pyrene‐alt‐difluorinated benzothiadiazole heterojunctions were constructed and the photophysical processes were investigated with femtosecond transient absorption spectroscopy. Encouragingly, an interfacial charge‐transfer signal was detected in the spectra of the heterojunction, which provides solid evidence for S‐scheme charge transfer to complement the results from well‐established methods. Furthermore, the lifetime for interfacial charge transfer was calculated to be ca. 78.6 ps. Moreover, the S‐scheme heterojunction photocatalysts exhibit higher photocatalytic conversion of 1,2‐diols and H2 production rates than bare cadmium sulfide. [ABSTRACT FROM AUTHOR]

The S‐scheme heterojunction is flourishing in photocatalysis because it concurrently realizes separated charge carriers and sufficient redox ability. Steady‐state charge transfer has been confirmed by other methods. However, an essential part, the transfer dynamics in S‐scheme heterojunctions, is still missing. To compensate, a series of cadmium sulfide/pyrene‐alt‐difluorinated benzothiadiazole heterojunctions were constructed and the photophysical processes were investigated with femtosecond transient absorption spectroscopy. Encouragingly, an interfacial charge‐transfer signal was detected in the spectra of the heterojunction, which provides solid evidence for S‐scheme charge transfer to complement the results from well‐established methods. Furthermore, the lifetime for interfacial charge transfer was calculated to be ca. 78.6 ps. Moreover, the S‐scheme heterojunction photocatalysts exhibit higher photocatalytic conversion of 1,2‐diols and H2 production rates than bare cadmium sulfide. [ABSTRACT FROM AUTHOR]

Electron density regulation of active sites can realize an optimal hydrogen‐binding strength, whereas the underlying regulation mechanism is still indistinct. Herein, a new concept of antibonding‐orbital occupancy state is first proposed to unveil the fundamental influence mechanism of electron density on the SeHads bond strength for achieving first‐rank adsorption energy toward atomic hydrogen by constructing Se‐enriched surrounding to form electron‐deficient Se(2‐δ)‐ active sites in ReSe2+x nanodots. To this end, the Se‐rich ReSe2+x nanodots (0.3–1 nm) can be dexterously fabricated onto the TiO2 to prepare Se‐rich ReSe2+x/TiO2 by an ingenious one‐step photosynthesis route. In a surprise, a large number of visual H2 bubbles are continuously produced on the resultant ReSe2+x/TiO2(0.7 wt.%) with an ultrahigh rate of 12 490.4 µmol h−1 g−1 and an apparent quantum efficiency of 60.0%, which is 5.0 times higher than that of traditional ReSe2/TiO2, even comparable with benchmark Pt/TiO2(0.7 wt.%). In situ/ex situ XPS characterizations coupled with density functional theory (DFT) calculations corroborate that a Se‐enriched environment can induce the formation of electron‐deficient Se(2‐δ)− and then reduce its antibonding‐orbital occupancy state, thus increasing the stability of H 1s‐p antibonding and accordingly reinforcing the SeHads bonds. This holistic study identifies the dominant role of antibonding‐orbital occupancy states in the optimization of hydrogen‐binding energy. [ABSTRACT FROM AUTHOR]

Femtosecond transient absorption spectroscopy (fs-TAS) is a powerful technique for monitoring the electron transfer kinetics in photocatalysis. Several important works have successfully elucidated the electron transfer mechanism in heterojunction photocatalysts (HPs) using fs-TAS measurements, and thus a timely summary of recent advances is essential. This feature article starts with a thorough interpretation of the operating principle of fs-TAS equipment, and the fundamentals of the fs-TAS spectra. Subsequently, the applications of fs-TAS in analyzing the dynamics of photogenerated carriers in semiconductor/metal HPs, semiconductor/carbon HPs, semiconductor/semiconductor HPs, and multicomponent HPs are discussed in sequence. Finally, the significance of fs-TAS in revealing the ultrafast interfacial electron transfer process in HPs is summarized, and further research on the applications of fs-TAS in photocatalysis is proposed. This feature article will provide deep insight into the mechanism of the enhanced photocatalytic performance of HPs from the perspective of electron transfer kinetics. [ABSTRACT FROM AUTHOR]

[Display omitted] • Super-hydrophilic PNF with hierarchically porous structure was fabricated. • Fe-Ni 3 S 2 /PNF was fabricated via mild and scalable electro-deposition strategies. • Fe-Ni 3 S 2 /PNF shows 10 mA cm−2 at 1.50 V cell voltage for overall water splitting. • Fe-Ni 3 S 2 /PNF shows excellent activity and durability under industrial conditions. Alkaline water electrolysis (AWE) offers a promising route for green hydrogen production. However, its industrial application is impeded by unsatisfactory energy conversion efficiency. Herein, a robust electrode composed of porous nickel foam (PNF) and Fe-doped Ni 3 S 2 (Fe-Ni 3 S 2) nanosheet arrays was fabricated and applied for industrial AWE. By conducting a scalable dynamic bubble-template method, PNF with high loading of active catalysts was prepared. The superhydrophilicity of PNF facilitates bubble detachment and promotes mass transfer, especially at high current densities. In addition, Fe-Ni 3 S 2 with optimized electronic structure is featured with enhanced electrical conductivity, sufficient exposure of active sites, and optimized adsorption of intermediates. Benefiting from the concerted advantages of PNF and Fe-Ni 3 S 2 , the obtained Fe-Ni 3 S 2 /PNF-5 electrode with an optimal Fe content of 5 mol% exhibits high catalytic activity for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Compared with the Pt/C/NF||IrO 2 /NF couple, the Fe-Ni 3 S 2 /PNF-5||Fe-Ni 3 S 2 /PNF-5 couple delivers a current density of 10 mA cm−2 at a low cell voltage of 1.50 V for AWE. Under industrial conditions, a competitive cell voltage of 1.75 V is needed for achieving a high current density of 400 mA cm−2. Besides, the couple can operate stably for 120 h, outperforming the commercial RN||RN couple. This work provides a novel strategy to elevate the loading amount of catalysts and improve the electrochemical performance of the electrode for practical AWE application. [ABSTRACT FROM AUTHOR]

The aggravating extreme climate changes and natural disasters stimulate the exploration of low‐carbon/zero‐carbon alternatives to traditional carbon‐based fossil fuels. Solar‐to‐hydrogen (STH) transformation is considered as appealing route to convert renewable solar energy into carbon‐free hydrogen. Restricted by the low efficiency and high cost of noble metal cocatalysts, high‐performance and cost‐effective photocatalysts are required to realize the realistic STH transformation. Herein, the 2D FePS3 (FPS) nanosheets anchored with TiO2 nanoparticles (TiO2/FePS3) are synthesized and tested for the photocatalytic hydrogen evolution reaction. With the integration of FPS, the photocatalytic H2‐evolution rate on TiO2/FePS3 is radically increased by ≈1686%, much faster than that of TiO2 alone. The origin of the greatly raised activity is revealed by theoretical calculations and various advanced characterizations, such as transient‐state photoluminescence spectroscopy/surface photovoltage spectroscopy, in situ atomic force microscopy combined with Kelvin probe force microscopy (AFM‐KPFM), in situ X‐ray photoelectron spectroscopy (XPS), and synchrotron‐based X‐ray absorption near edge structure. Especially, the in situ AFM‐KPFM and in situ XPS together confirm the electron transport pathway in TiO2/FePS3 with light illumination, unveiling the efficient separation/transfer of charge carrier in TiO2/FePS3 step‐scheme heterojunction. This work sheds light on designing and fabricating novel 2D material‐based S‐scheme heterojunctions in photocatalysis. [ABSTRACT FROM AUTHOR]

[Display omitted] • NiFe LDH hollow microspheres were synthesized for tetracycline adsorption. • The adsorption of TC on NFHMS surface is mainly by electrostatic interaction. • The maximum theoretical value of monolayer adsorption of TC on NFHMS surface is 90.9 mg g−1. • The adsorption process of TC on NFHMS surface is spontaneous and endothermic. • The value of pH affects the adsorption properties by changing the type of charge on the surface of the material. Tetracycline (TC) has poor degradability and hepatotoxicity which will increase the burden on the aquatic environment when discharged into lakes in large quantities. LDH materials are often used as adsorbents because of their superior surface area and controllability of morphology. Herein, NiFe LDH hollow microspheres (NFHMS) were synthesized by a facile hydrothermal method. The removal of tetracycline by the as-prepared material in an aquatic environment was systematically investigated through comprehensive characterizations. The NFHMS sample presents a larger specific surface area than the two control samples, which contributes to its higher adsorption performance. The adsorption mechanisms of TC on NFHMS is mainly electrostatic adsorption. The fitting results of experimental data coincide well with pseudo-second-order and Weber-Morris models through kinetic simulation. Moreover, the Langmuir model is verified to be more suitable than the Freundlich model in elucidating molecular surface adsorption, and the maximum adsorption capacity of NFHMS obtained from the Langmuir model is 90.9 mg g−1. Higher temperature is beneficial to improve the adsorption performance, and the adsorption process is spontaneous and endothermic. The initial pH of the solution will affect the adsorption capacity, and the partial neutral condition is more favorable. In addition, NFHMS sample exhibits good stability in cyclic tests. Therefore, NFHMS material is expected to be a very promising adsorbent for treating tetracycline in wastewater. [ABSTRACT FROM AUTHOR]

An optimized approach to producing lattice‐matched heterointerfaces for electrocatalytic hydrogen evolution has not yet been reported. Herein, we present the synthesis of lattice‐matched Mo2C−Mo2N heterostructures using a gradient heating epitaxial growth method. The well lattice‐matched heterointerface of Mo2C−Mo2N generates near‐zero hydrogen‐adsorption free energy and facilitates water dissociation in acid and alkaline media. The lattice‐matched Mo2C−Mo2N heterostructures have low overpotentials of 73 mV and 80 mV at 10 mA cm−2 in acid and alkaline solutions, respectively, comparable to commercial Pt/C. A novel photothermal‐electrocatalytic water vapor splitting device using the lattice‐matched Mo2C−Mo2N heterostructure as a hydrogen evolution electrocatalyst displays a competitive cell voltage for electrocatalytic water splitting. [ABSTRACT FROM AUTHOR]

An optimized approach to producing lattice‐matched heterointerfaces for electrocatalytic hydrogen evolution has not yet been reported. Herein, we present the synthesis of lattice‐matched Mo2C−Mo2N heterostructures using a gradient heating epitaxial growth method. The well lattice‐matched heterointerface of Mo2C−Mo2N generates near‐zero hydrogen‐adsorption free energy and facilitates water dissociation in acid and alkaline media. The lattice‐matched Mo2C−Mo2N heterostructures have low overpotentials of 73 mV and 80 mV at 10 mA cm−2 in acid and alkaline solutions, respectively, comparable to commercial Pt/C. A novel photothermal‐electrocatalytic water vapor splitting device using the lattice‐matched Mo2C−Mo2N heterostructure as a hydrogen evolution electrocatalyst displays a competitive cell voltage for electrocatalytic water splitting. [ABSTRACT FROM AUTHOR]

The best use of photogenerated electrons and holes is crucial to boosting photocatalytic activity. Herein, a bifunctional dual‐cocatalyst‐modified photocatalyst is constructed based on CdS/MoO2/MoS2 hollow spheres for hydrogen evolution coupled with selective pyruvic acid (PA) production from lactic acid (LA) oxidation. MoS2 and MoO2 are simultaneously obtained from the conversion of CdMoO4 in one step. In a photocatalytic process, the MoS2 and MoO2 function as the reduction and oxidation centers on which photogenerated electrons and holes accumulate and are used for hydrogen evolution reaction (HER) and PA synthesis, respectively. By monitoring the intermediates, a two‐step single‐electron route for PA production is proposed, initiated by the cleavage of the α‐C(sp3)−H bond in the LA. The conversion of LA and the selectivity of PA can reach ca. 29 % and 95 % after a five‐hour reaction, respectively. [ABSTRACT FROM AUTHOR]

The best use of photogenerated electrons and holes is crucial to boosting photocatalytic activity. Herein, a bifunctional dual‐cocatalyst‐modified photocatalyst is constructed based on CdS/MoO2/MoS2 hollow spheres for hydrogen evolution coupled with selective pyruvic acid (PA) production from lactic acid (LA) oxidation. MoS2 and MoO2 are simultaneously obtained from the conversion of CdMoO4 in one step. In a photocatalytic process, the MoS2 and MoO2 function as the reduction and oxidation centers on which photogenerated electrons and holes accumulate and are used for hydrogen evolution reaction (HER) and PA synthesis, respectively. By monitoring the intermediates, a two‐step single‐electron route for PA production is proposed, initiated by the cleavage of the α‐C(sp3)−H bond in the LA. The conversion of LA and the selectivity of PA can reach ca. 29 % and 95 % after a five‐hour reaction, respectively. [ABSTRACT FROM AUTHOR]

Regulating molecular structure of donor‐acceptor (D‐A) polymer is a promising strategy to improve photoactivity. Herein, a porous nanorod‐like D‐A polymer is synthesized via a strategy of supramolecular chemistry combined with subsequent calcination treatment. This polymer consists of benzene rings (D) and triazine (A) that are linked by amido bond (−CONH−). −CONH− further partially cracks into cyano groups (−C≡N) (A) under calcination. The ratio of benzene to triazine could be tuned to adjust the −C≡N content by varying the calcination atmosphere. Such regulation of molecular structure could modulate the band structure of D‐A polymer and endow it with unique porous nanorod‐like morphology, leading to the achievement of two‐electron oxygen reduction and two‐electron water oxidation and the improvement of exciton splitting, O2 adsorption and activation. These merits synergistically ensure a highly efficient and stable photocatalytic H2O2 production in pure water. [ABSTRACT FROM AUTHOR]

Regulating molecular structure of donor‐acceptor (D‐A) polymer is a promising strategy to improve photoactivity. Herein, a porous nanorod‐like D‐A polymer is synthesized via a strategy of supramolecular chemistry combined with subsequent calcination treatment. This polymer consists of benzene rings (D) and triazine (A) that are linked by amido bond (−CONH−). −CONH− further partially cracks into cyano groups (−C≡N) (A) under calcination. The ratio of benzene to triazine could be tuned to adjust the −C≡N content by varying the calcination atmosphere. Such regulation of molecular structure could modulate the band structure of D‐A polymer and endow it with unique porous nanorod‐like morphology, leading to the achievement of two‐electron oxygen reduction and two‐electron water oxidation and the improvement of exciton splitting, O2 adsorption and activation. These merits synergistically ensure a highly efficient and stable photocatalytic H2O2 production in pure water. [ABSTRACT FROM AUTHOR]

Graphdiyne is an emerging material widely used in photocatalysis. Its excellent physicochemical properties, such as nonuniform electron distribution, uniform pore distribution, excellent electron mobility, and high chemical stability, make it promising for solar fuel production. Given the rapid development of graphdiyne-based photocatalysts and their application in solar fuel production, a timely review of this field is urgently needed. This paper summarises the structure, properties, synthesis and characterisation of graphdiyne, and the achievements of graphdiyne-based photocatalysts in solar fuel production, including H2 evolution, CO2 reduction and N2 fixation. The challenges and outlook of graphdiyne-based photocatalysts for efficient solar fuel production are presented. This paper is expected to provide new insights into graphdiyne-based photocatalysts for solar fuel production. [ABSTRACT FROM AUTHOR]

Chlorine evolution reaction (CER) in chlor-alkali industry is limited by oxygen evolution reaction (OER) due to their common active sites and close standard reaction potentials. Herein, a ternary RuSnTi electrode was synthesized and exhibits a superior CER activity in saturated NaCl solution. Theoretical studies reveal that Ru dopant improves the electrical conductivity of RuSnTi by contributing Ru orbitals to the energy band curves through/near the Fermi level. RuSnTi delivers a current density of 96.6 mA cm−2 at potential of 1.15 V (saturated calomel electrode, SCE), much higher than that of the dimensionally stable anode (DSA). Moreover, the inhibitory effect of Sn species on OER endows RuSnTi with a high Cl 2 selectivity of 95.7%. Besides, RuSnTi shows good stability during long-term stability test by stably operating 240 h at 100 mA cm−2 in saturated NaCl solution (pH = 7), highlighting the great potential in practical application. This work provides new insights into the development of high-performance Ru-based CER electrodes. [Display omitted] • Cl 2 selectivity of RuSnTi was predicted based on adsorption energy of Cl− and OH− ions. • RuSnTi delivers a high current density of 96.6 mA cm−2 at potential of 1.15 V (vs. SCE). • RuSnTi exhibits the highest Cl 2 selectivity of 95.7% in neutral saturated NaCl solution. • RuSnTi shows excellent stability in neutral and acidic saturated NaCl solution. [ABSTRACT FROM AUTHOR]

Sluggish charge kinetics and moderate adsorption–desorption ability of gas molecules are major limitations for photocatalytic NO x elimination of bulk g-C 3 N 4. A hierarchical porous g-C 3 N 4 photocatalyst modified with N vacancies and charge channels (KCNN) was prepared by thermal polymerisation in KCl medium followed by quenching to increase the photocatalytic efficiency. The optimized KCNN sample exhibits highly enhanced photocatalytic NO removal rate (70.5%), which is superior to those of bulk g-C 3 N 4 (38.1%), porous g-C 3 N 4 (54.5%) and K-doped g-C 3 N 4 (58.6%), respectively. X-ray photoelectron spectroscopy and electron paramagnetic resonance data reveal the successful formation of N vacancy in g-C 3 N 4 framework. The enhanced activity of KCNN is ascribed to the enlarged surface area, expanded light absorption, low charge recombination efficiency and strong oxidation capability, respectively. In situ DRIFTS and density functional theory results suggest that the introduction of N vacancies and K+ ions enable control over NO adsorption and activation, leading to the implementation of a preferred pathway (NO → NO+ → NO 3 ‾) and reduction in the emission of toxic intermediates. This work presents a potential idea for improving the charge transfer of layered materials and optimising the diffusion/adsorption/activation of gas molecules for photocatalytic NO oxidation. [Display omitted] • A hierarchical porous g-C 3 N 4 with N vacancies and charge channels is successfully synthesized. • The optimized KCNN sample exhibits improved photocatalytic NO removal rate and toxic by-product suppression. • DFT calculations reveal that the N vacancies accelerate the adsorption and activation of NO on the g-C 3 N 4 surface. • In-situ DRIFTS revealed the photo-oxidation mechanism of NO on KCNN through a preferred pathway (NO → NO+ → NO 3 ‾). • The synergy of hierarchical porous structure, N vacancy and K+ ions boost photocatalytic NO x removal activity of KCNN. [ABSTRACT FROM AUTHOR]

The development of highly active single‐atom catalysts (SACs) and identifying their intrinsic active sites in oxidizing industrial hazardous hydrocarbons are challenging prospects. Tuning the electronic metal‐support interactions (EMSIs) is valid for modulating the catalytic performance of SACs. We propose that the modulation of the EMSIs in a Pt1−CuO SAC significantly promotes the activity of the catalyst in acetone oxidation. The EMSIs promote charge redistribution through the unified Pt−O−Cu moieties, which modulates the d‐band structure of atomic Pt sites, and strengthens the adsorption and activation of reactants. The positively charged Pt atoms are superior for activating acetone at low temperatures, and the stretched Cu−O bonds facilitate the activation of lattice oxygen atoms to participate in subsequent oxidation. We believe that this work will guide researchers to engineer efficient SACs for application in hydrocarbon oxidation reactions. [ABSTRACT FROM AUTHOR]

The development of highly active single‐atom catalysts (SACs) and identifying their intrinsic active sites in oxidizing industrial hazardous hydrocarbons are challenging prospects. Tuning the electronic metal‐support interactions (EMSIs) is valid for modulating the catalytic performance of SACs. We propose that the modulation of the EMSIs in a Pt1−CuO SAC significantly promotes the activity of the catalyst in acetone oxidation. The EMSIs promote charge redistribution through the unified Pt−O−Cu moieties, which modulates the d‐band structure of atomic Pt sites, and strengthens the adsorption and activation of reactants. The positively charged Pt atoms are superior for activating acetone at low temperatures, and the stretched Cu−O bonds facilitate the activation of lattice oxygen atoms to participate in subsequent oxidation. We believe that this work will guide researchers to engineer efficient SACs for application in hydrocarbon oxidation reactions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hierarchical Pt/Co 3 O 4 -NiO catalyst prepared from MOFs with excellent activity. • Hollow and porous structure with low air resistance and fast diffusion channels. • Abundant active oxygen species at the interface between Co 3 O 4 and NiO. • Enhanced O 2 adsorption and activation due to the electron transfer from NiO to Pt. • Possible mechanism for HCHO oxidation over Pt/Co 3 O 4 -NiO proposed. Room-temperature catalytic decomposition is considered a predominant approach for the continuous and efficient elimination of indoor formaldehyde (HCHO). Herein, Co 3 O 4 -NiO hollow dodecahedra were prepared by using ZIF-67 as a precursor and decorated with 0.3 wt% platinum nanoparticles (Pt NPs). The hierarchical porous Pt/Co 3 O 4 -NiO catalyst exhibited an excellent room-temperature HCHO decomposition performance, and 93% conversion was achieved within 60 min. Numerous active oxygens at the interface between Co 3 O 4 and NiO and the oxygen vacancies generated during Pt deposition were favorable for the adsorption and conversion of HCHO to Dioxymethylene (DOM). Moreover, the electron transfer from NiO to Pt rendered Pt NPs more effective in adsorbing and activating O 2 molecules, thereby promoting the further oxidation of DOM to formate and CO 2. Importantly, the hierarchical structure of the Co 3 O 4 -NiO support with a large surface area participated in the uniform distribution and easy accessibility of Pt active sites. In addition, the hollow and porous structure enabled Pt/Co 3 O 4 -NiO catalyst to possess ultra-low gas resistance, which is important for gas–solid HCHO oxidation. This work may provide clues for the fabrication of MOF-derived catalysts for HCHO decomposition with high efficiency. [ABSTRACT FROM AUTHOR]

2D carbides and nitrides of transition metals, also known as MXenes, are an emerging class of 2D nanomaterials that have shown excellent performances and broad application prospects in the fields of energy storage, catalysis, sensing, electromagnetic shielding, electronics and photonics, and life sciences. This unusual diversity of applications is due to their superior hydrophilicity and conductivity, high carrier concentration, ultra-high volumetric capacitance, rich surface chemistry, and large specific surface area. However, it is difficult to make MXenes with the desired surface functional groups that deliver high reactivity and high stability, because most MXenes are extracted from ceramics (MAX phase) by an etching process, where a large number of metal atoms are inevitably exposed on the surface, with other anions and cations embedded uncontrollably. The exposed metal atoms and implanted ions are thermodynamically unstable and readily react with trace oxygen or oxygen-containing groups to form the corresponding metal oxides or degrade chemically, resulting in a sharp decline in activity and loss of excellent physicochemical properties. The addition of certain synergistic additives during the intercalation and chemical modification of surface functional groups under non-hazardous conditions can result in stable and efficient MXene-based materials with exceptional optical, electrical, and magnetic properties. This review discusses several such methods, mainly additive-mediated intercalation and chemical modification of the surface functional groups of MXene-based materials, followed by their potential applications. Finally, perspectives are given to discuss the future challenges and promising opportunities of this exciting field. [ABSTRACT FROM AUTHOR]

[Display omitted] • Polyhedron MNC HS was synthesized using ZIF-67 as template. • It has a porous structure and large specific surface area. • It showed excellent adsorption capacity and good recovery for Congo red. • It can be as a promising candidate for removal of CR pollutants. Adsorption materials with large specific surface area and porous structures exert a beneficial impact on improving the adsorption performance. In this work, MgNiCo LDH hollow structure (MNC HS) is fabricated through a simple one-step solvothermal method using ZIF-67 as the sacrificial template. Electron microscopy shows that the MNC HS retains the dodecahedral shape of ZIF-67. The as-prepared sample exhibits efficient adsorption for Congo red (CR) in water, which is due to the hierarchical structure and large specific surface area that provides more adsorption sites and electrostatic interaction. The CR adsorption process fits the pseudo-second-order model better by kinetics simulation; while Langmuir model is more accurate than Freundlich model in describing the adsorption isotherms of CR. The maximum adsorption capacity calculated by the Langmuir model can reach 1194.7 mg g−1, which is much higher than that of the sample MgNiCo LDH (MNC) synthesized by conventional methods. The cycle tests also show that the as-prepared adsorbent has good stability and recycling ability. [ABSTRACT FROM AUTHOR]

Room‐temperature oxidation over supported noble metals provides a feasible approach to eliminating formaldehyde (HCHO) from indoor air. Oxygen activation by noble metals such as gold and platinum plays a key role in achieving complete HCHO oxidation, but it is unclear how different noble metals function synergistically toward oxygen activation. Here, the synergistic mechanisms of Pt and Au nanoparticles (NPs) coloaded on TiO2 in catalytic HCHO oxidation are elucidated. Strikingly, ≈0.08% doping of Pt can dramatically improve the catalytic activity of 0.9% Au/TiO2. The surface oxygen species of TiO2 jointly activated by Au and Pt NPs can rapidly transform HCHO to dioxymethylene surface species, while negatively charged Pt NPs can efficiently adsorb and activate molecular oxygen to oxidize the dioxymethylene into formate, which is further completely oxidized. This synergy enables efficient HCHO oxidation at surface sites between adjacent Pt and Au NPs. [ABSTRACT FROM AUTHOR]

Sodium hybrid supercapacitors (Na‐HSCs) are regarded as one promising electrochemical energy storage device, because of the low price of sodium, prolonged life cycle, and high‐energy/power density. Nonetheless, the imparity between the fast capacitive reactions at cathode and the sluggish Faradaic reactions at the anode leads to an imbalance in the electrochemical reaction kinetics, limiting the development of Na‐HSCs. Therefore, it is urgent to develop suitable anode materials for performance‐enhanced Na‐HSCs. Herein, sandwich‐shell‐structured CoMn2O4/C hollow spheres are synthesized by a facile hydrothermal reaction and subsequent calcination, where mesoporous carbon hollow spheres (CHSs) serve as nonsacrificial hard templates. CHSs with numerous mesoporous channels are beneficial for the penetration of reactant ions. Therefore, CoMn2O4 nanosheets are successfully deposited on the inner and outer surfaces of CHSs, generating sandwich‐shell‐structured CoMn2O4/C hollow spheres. Benefiting from the unique design, CoMn2O4/C HSs exhibit excellent sodium storage performance, including a high‐specific capacity of 290 mAh g–1 at 0.1 A g–1 and prolonged cycling durability. A Na‐HSC assembled by CoMn2O4/C HSs anode and activated carbon cathode exhibits a high‐energy density (265 Wh kg–1) and a wide‐operating voltage range (0.01–4.0 V). [ABSTRACT FROM AUTHOR]

Lithium‐sulfur batteries, as viable options for energy storage, have gained popularity because of their high energy density. However, the poor conductivity of sulfur and Li2S, as well as the shuttling effect of lithium polysulfides, seriously limits their commercialization. Herein, cobalt chalcogenides (Co3O4, CoS, and Co3Se4) supported by reduced graphene oxide are synthesized as the electrode materials, which feature high conductivity, rapid kinetic conversion, and catalytic effect. Based on complementary experimental outputs and advanced computation, it is revealed that the change in anion results in distinctive performance. Among them, the cathode material based on Co3Se4/reduced graphene oxide is the best. The reasons can be ascribed to the conductive and catalytic improvement. This comparative study provides guidelines in the design of lithium‐sulfur batteries via the meticulous regulation of the anions. [ABSTRACT FROM AUTHOR]

Organic‐inorganic halide perovskite solar cells (PSCs) have drawn tremendous attention owing to their remarkable photovoltaic performance and simple preparation process. However, conventional wet‐chemical synthesis methods inevitably create defects both in the bulk and at the interfaces of perovskites, leading to recombination of charge carriers and reduced stability. Herein, a bilateral interface modification to perovskites by doping room‐temperature synthesized CsPbBr3 nanocrystals (CN) is reported. The ultrafast transient absorption measurement reveals that CN effectively suppresses the defect at the SnO2/perovskite interface and boosts the interfacial electron transport. Meanwhile, the in situ Kelvin probe force microscopy and contact potential difference characterizations verify that the CN within the upper part of the perovskites enhances the built‐in electric field, facilitating oriented migration of the carriers within the perovskite. Combining the superiorities of CN modifiers on both sides, the bilaterally modified CH3NH3PbI3‐based planar PSCs exhibit optimal power conversion efficiency exceeding 20% and improved device stability. [ABSTRACT FROM AUTHOR]

Coupling photocatalytic H2 production with organic synthesis attracts immense interest in the energy and chemical engineering field for the low‐cost, clean, and sustainable generation of green energy and value‐added products. Nevertheless, the performance of current photocatalysts is greatly limited by grievous charge recombination and tardy H2 evolution. To tackle these issues, a Pt nanocluster‐modified ZnCdS solid solution is fabricated for photocatalytic H2 production and selective furfuralcohol oxidation. The internal electric field inside the ZnCdS and Schottky junction between ZnCdS and Pt nanoclusters drastically ameliorate charge separation. Meanwhile, the Pt nanoclusters remarkably expedite the H2 evolution kinetics on ZnCdS. As a result, the H2 production rate over Pt‐loaded ZnCdS reaches 1045 µmol g−1 h−1, which is about 26‐ and 70‐fold that of CdS and ZnS, respectively. Under light irradiation for 3 h, the conversion of furfuralcohol to furfural reaches 71% with 89% furfural selectivity. The photocatalytic mechanism is investigated by in situ characterizations and theoretical calculations. [ABSTRACT FROM AUTHOR]

K and O co-doped ultrathin carbon nitride nanosheets prepared by one-step calcination with the assistance of K 2 S 2 O 8 exhibit much enhanced photocatalytic performance for CO 2 reduction under non-sacrificial and non-cocatalyst condition. [Display omitted] • The K and O atoms were co-doped into carbon nitride via one-step process by K 2 S 2 O 8. • The modified carbon nitride exbibits improved light absorption and charge separation. • The modified carbon nitride shows much enhanced CO2 photoreduction performance. Polymeric carbon nitride (CN) is a cheap and visible-light photocatalyst for potentially real application of CO 2 photoreduction into solar fuels. However, CN prepared by conventional one-step method always shows serious charge recombination and low charge mobility. Herein, we use urea as the starting material with K 2 S 2 O 8 to synthesize defect-modified ultrathin CN nanosheets. The as-prepared samples exhibit much higher photocatalytic CO 2 -reduction efficiency than the pristine CN with the production of CO and CH 4 fuels. The enhanced photocatalytic activity of modified samples is ascribed to the co-doping of K and O atoms into the CN frameworks, which promotes electron transfer from the bulk to the interface and narrows the band gap to provide a broad range of visible-light response. This work provides a simple but effective strategy to prepare defect-modified polymeric carbon nitride for various photocatalytic applications. [ABSTRACT FROM AUTHOR]

[Display omitted] It is imperative to seek for novel materials with pronounced gas sensing performance towards triethylamine for the sake of human health. Herein, we successfully fabricate an outstanding triethylamine sensor based on CdS/ZnO composite with 0D/2D structure, which are prepared by in-situ growth of CdS quantum dots on ultra-thin ZnO nanosheets. The ratios between the two ingredients are adjusted and their effect is evaluated. The optimal sample exhibits the lowest operating temperature of 200 °C, the highest response value of ~20 and the fastest response time of 2 s. Besides, it also has the virtues of durable stability, excellent selectivity and superior anti-interference ability. The mechanism behind the aforementioned intriguing performance is investigated by X-ray photoelectron spectroscopy, Kelvin probe and density function theory (DFT) simulation. All the results verify that the enhanced gas sensing properties are derived from splendid 0D/2D structure, n - n heterojunction and large specific surface area. Additionally, this study opens an avenue for designing sensors with 0D/2D structure. [ABSTRACT FROM AUTHOR]

Photocatalytic production of H2O2 from water and atmospheric oxygen has been recognized as a green and sustainable chemical process, due to the abundance of raw materials and sustainable solar energy. Herein, flower-like hierarchical ZnO microspheres were prepared by hydrothermal method followed by calcination at different temperatures, and their photocatalytic performance in H2O2 production was examined under simulated sunlight irradiation. The calcination temperature plays a vital role in the structure, morphology, and surface area of the final ZnO products as well as their optical and electrochemical properties, which are determining factors in their photocatalytic activity. The ZnO calcined at 300 °C (Zn-300) exhibits the highest activity and optimal stability, showing productivity of 2793 μmol l−1 within 60 min of irradiation, which was 6.5 times higher than that of uncalcined ZnO precursor. The remarkable photocatalytic activity is attributed to enhanced light utilization, large surface area, abundant exposed active sites, improved separation efficiency, and prolonged carrier lifespan. Moreover, the results from cycling experiments indicate the as-prepared ZnO samples exhibit good stability and long-time performance. This work provides useful information for the preparation of hierarchical ZnO photocatalysts. [ABSTRACT FROM AUTHOR]

Photocatalytic hydrogen production is enchanting in solar energy utilization. And mechanism elucidation in interfacial electron transfer rate is a prerequisite for performance improvement. Herein, atomically dispersed Pt-modified CdS quantum dots (Pt-CdS QDs), prepared by a facile one-step in-situ deposited method, are used as a prototype. Benefiting from the maximized utilization of Pt cocatalyst as well as the strong electronic metal-support interaction, ultrafast electron transfer from CdS to Pt (∼1.7 ps) is achieved, as revealed by femtosecond transient absorption spectra. The optimal sample simultaneously realizes photocatalytic hydrogen evolution coupled with selective oxidation of 2-thiophene methanol (TM) into 2-thiophenecarboxaldehyde (TD). Specifically, it exhibits an enhanced H 2 -evolution rate, which is 70-fold higher than pristine CdS QDs. Moreover, a TM conversion rate of 95.3 % with a TD selectivity of 87.2 % is reached after 4 h. This work will provide some guidance for the design of photocatalytic systems with efficient interfacial electron transfer. [Display omitted] • Atomically-dispersed Pt-modified CdS quantum dots were prepared. • A facile one-step approach was used for the synthesis of photocatalysts. • Enhanced H 2 production coupled with selective oxidation of 2-thiophene methanol. • Both photogenerated electrons and holes are efficiently utilized through this system. • Ultrafast electron transfer from CdS to Pt (∼1.7 ps) is revealed. [ABSTRACT FROM AUTHOR]

Manufacturing efficient and durable electrodes for alkaline water electrolysis under high-current-density conditions is a great challenge. Herein, Ni/Ni x S y heterostructure was grown on designed porous nickel foam (PNF) to construct Ni/Ni x S y -PNF electrode by a facile and scalable method for alkaline hydrogen evolution reaction (HER). The hierarchical porous structure and super-hydrophilic surface of Ni/Ni x S y -PNF accelerate the mass transfer and bubble detachment at high current densities. Theoretical calculations reveals that the enhanced HER activity of Ni/Ni x S y heterostructure is attributed to the stronger H 2 O adsorption. The resulting Ni/Ni x S y -PNF electrode achieves current densities of 100 and 500 mA cm−2 at low overpotentials of 61 and 121 mV, respectively. When applied for overall water splitting, the Ni/Ni x S y -PNF||Fe-Ni 3 S 2 -PNF electrolyser reaches a current density of 10 mA cm−2 at an extremely low voltage of 1.32 V. This work provides an effective strategy for fabricating high-performance electrodes for practical water electrolysis. [Display omitted] ● Porous nickel foam (PNF) substrate was prepared by a dynamic bubble template method. ● Crystalline/amorphous Ni/Ni x S y heterostructure was supported on PNF by an in-situ electrochemical method. ● Hierarchical Ni/Ni x S y -PNF electrode exhibited superior electrocatalytic HER performance with enhanced Volmer step. ● Ni/Ni x S y -PNF electrode is efficient and robust under industrial conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] • This novel inorganic/organic CdS/COF 2D-2D S-scheme heterostructure is designed. • The structure can reduce charge transfer distance, and improve light absorption. • This S-scheme heterojunction enhances charge separation and retains redox ability. • The CdS/COF exhibits a remarkable photocatalytic H 2 production rate. • The heterojunction converts ascorbic acid to value-added 2,3-diketo-L-gulonic acid. It is an efficient strategy to construct photocatalysts by integrating the advantages of inorganic semiconductors and covalent organic frameworks (COFs) for H 2 generation along with simultaneous organic oxidation. Herein, an inorganic/organic CdS/COF (denoted as TpBD) 2D heterostructure is fabricated by an electrostatic self-assembly method. The ultrathin 2D structure can reduce charge transfer distance, enhance light absorption, and multiply reaction sites while the S-scheme heterojunction improves the charge separation efficiency. The CdS/COF composite acquires an outstanding photocatalytic activity of 15.1 mmol/g/h, and can simultaneously convert cheap ascorbic acid to value-added 2,3-diketo-L-gulonic acid. The Hall effect test elucidates the dynamics of carrier migration. The electron paramagnetic resonance analysis, photo-irradiated Kelvin probe force microscopy, femtosecond transient absorption spectroscopy, theoretical calculation, and in-situ irradiation X-ray photoelectron spectroscopy measurements confirm the superiority of S-scheme heterojunction for charge carrier transfer. This research presents new inspiration to develop efficient photocatalysts for hydrogen production and green chemical production. [ABSTRACT FROM AUTHOR]

Coupling photocatalytic H 2 O 2 evolution with simultaneous furfuryl alcohol oxidation can avoid the slow water oxidation reaction and fully utilize photogenerated carriers to produce valuable chemicals. Herein, a COF (denoted as BTTA) was synthesized by the Schiff-base condensation and in-situ grown on the surface of TiO 2 nanofibers. The resultant TiO 2 /BTTA composite has a large interface and a short carrier migration distance. Furthermore, the porous and ultrathin BTTA layers endow the composites abundant active sites and excellent light absorption ability. Remarkably, a H 2 O 2 -evolution rate of 740 μmol L−1 h−1 and a furoic alcohol conversion of 96 % are achieved. In-situ irradiated X-ray photoelectron spectroscopy and electron spin resonance confirm the S-scheme carrier transfer mechanism, which spatially separates photogenerated carriers with strong redox power. This work opens a new door to the rational design of S-scheme photocatalysts for economic and green photosynthesis of H 2 O 2 and organic compounds. [Display omitted] • The novel TiO 2 /BTTA S-scheme heterojunction photocatalysts were constructed. • TiO 2 /BTTA nanocomposites possess high surface area, abundant active sites and excellent visible light absorption. • S-scheme mechanism and pathways of H 2 O 2 and furoic acid evolution was verified. • The S-scheme heterojunction improved the utilization efficiency of charge and retained great redox capacity. [ABSTRACT FROM AUTHOR]

• Zinc porphyrin/g-C 3 N 4 S-scheme photocatalyst is developed via –CONH-bridging bond. • Zn-TCPP/CN exhibits H 2 O 2 production rate with 3.1 times higher than pure CN. • Two-step single-electron route is the predominant reaction step in H 2 O 2 generation. • S-scheme charge transfer path greatly facilitates the spatial charge separation. • DFT reveals strong interface interaction with the electron delocalization effect. Constructing heterojunction photocatalyst is a promising strategy to achieve solar-to-chemical energy conversion. Especially, the S-scheme heterojunction has received a great deal of attention because of its superiority of the efficient photogenerated charge carriers' separation and the strong photoredox capacity. Herein, an S-scheme heterojunction is designed and synthesized through grafting supramolecular Zinc porphyrin (Zn-TCPP) on g-C 3 N 4 (CN) via –CONH- bridging bond for H 2 O 2 production in the O 2 atmosphere under a 300 W Xe lamp irradiation using ethanol as a sacrificial agent. As the optimal sample, Zn-TCPP/CN exhibits the highest H 2 O 2 production rate with 532.7 μmol/L within 90 min, which is 3.1 and 9.0 times higher than those of pure CN and Zn-TCPP, respectively. The route of H 2 O 2 production in the photocatalytic process and the mechanism of activity enhancement are revealed by a systematic characterisation. Hence, the results of the radical trapping experiment and rotating disk electrode measurement demonstrate that the two-step single-electron route is the predominant reaction step in the process of H 2 O 2 generation. In-situ irradiated X-ray photoelectron spectroscopy (ISI-XPS) and Kelvin probe force microscopy (KPFM) technology provide strong evidence of the S-scheme charge transfer path between Zn-TCPP and CN, which greatly facilitates the spatial charge separation. Meanwhile, the density functional theory (DFT) calculations reveal that the strong interface interaction between Zn-TCPP and CN can induce the electron delocalization effect, thus restraining charge recombination. This work inspired the design of a high-active metalloporphyrin-based S-scheme heterojunction for energy conversion. [ABSTRACT FROM AUTHOR]

As we all know, formaldehyde (HCHO) is extremely harmful to human health and has been identified as a primary carcinogen by the World Health Organization. Therefore, there is an urgent need to design efficient formaldehyde-sensing materials. In this work, a highly responsive formaldehyde sensor of In 2 O 3 @ZnO derived from MIL-68(In)@ZIF-8 precursor was successfully prepared. By adjusting the ratio of In 2 O 3 and ZnO, it can be found that the performance of the resulting sensor has greatly improved under 100 ppm HCHO at an operating temperature of 220 °C and the detection limit can be as low as 4 ppb. Additionally, it also has excellent selectivity (Q≥10), anti-interference (the deviation value≤3.5%), and long-lasting stability (the variation value≤4%). Such distinguished sensing performance can be attributed to the metal-organic framework (MOF) derived step-scheme (S-scheme) heterojunction, which ultimately increases the adsorption of oxygen and HCHO. This work verifies that ingenious heterojunction construction can significantly improve gas sensing performance. • The composite of In 2 O 3 /ZnO-5 is derived from dual MOF. • In 2 O 3 /ZnO-5 sensor displays distinguished sensing behaviors towards HCHO. • Its response value (∼190) is very high without loading noble metals. • Such excellent performance is ascribed to S-scheme heterojunction. [ABSTRACT FROM AUTHOR]