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Co-catalyst loading on photoelectrodes is considered to be an effective way to accelerate charge transfer. However, the bonding between most of the co-catalysts and photoelectrodes tends to be weak, which severely limits the role of co-catalysts in the catalytic system. Based on the above problems, we introduced trifluoroacetic acid (TFA) as a homogeneous molecular co-catalyst in the layered BiOIO 3 catalytic system for the first time. The BiOIO 3 -TFA photoelectrode exhibited excellent photoelectrochemical performance under light and applied bias voltage. The photocurrent density reached up to 0.228 μA cm−2, which was 2.11 times higher than that before modification, while the overpotential was negatively shifted by 183 mV. The results showed that the photogenerated electron-hole pairs in BiOIO 3 are excited and transferred to the TFA causing the C O double bond to break to form a TFA radical (TFA ·), which is then reduced to TFA - . This cyclic redox reaction accompanied by fast hole transfer can greatly reduce the recombination behavior during carrier transport. This work demonstrates a new form of co-catalyst for photoelectrochemical water splitting. Highly water-soluble molecules and TFA · /TFA - reversible reactions have considerable potential for the development of new co-catalysts. It also provides ideas for the establishment of new, efficient catalytic systems for inhibiting carrier recombination. [Display omitted] • A novel homogeneous TFA molecule was loaded on BiOIO 3 as a co-catalyst. • Reversible redox reaction of TFA · /TFA - accompanied by fast hole transfer. • TFA molecules can effectively suppress recombination during carrier transport. • BiOIO 3 -TFA photoelectrode exhibits excellent PEC performance under light and applied bias voltage. [ABSTRACT FROM AUTHOR]

The efficient and high-quality production for hydrogen through water electrolysis at high current densities is crucial for commercial utilization. However, the performance of existing hydrogen evolution reaction (HER) electrocatalysts is far from satisfactory. In this regard, we proposed a method to prepare Rh–Ni(OH) 2 catalyst based on Nickel foam (NF). The hydrolysis galvanic replacement of nickel boride with RhCl 3 led to produce a lattice contraction in Ni(OH) 2 due to the rigid pressure generated, resulting in outstanding HER performance at high current densities. It achieves an industrial current density of 500 mA cm−2 with an overpotential of 130 mV. Furthermore, at the industrially prefer temperature of 80 °C, only 67 mV overpotential is required. The catalyst also demonstrated exceptional stability, maintaining excellent performance even after a stability test of 100 days with a current density of 200 mA cm−2. Through Density-functional theory (DFT) calculations, Rh series reduced the hydrogen adsorption free energy. The electronic structure of Ni was improved by pretreatment with NaBH 4 , and then it reacted with Rh species, triggering the lattice contraction of Ni(OH) 2 , and the existence of this effect makes Rh play an active site role at the same time, and Ni also plays an auxiliary role in its role. The result is a highly efficient catalyst (Rh–Ni(OH) 2 /NF) for HER that achieves a current density of 500 mA cm−2 at only 130 mV and remains stable for three months under constant current conditions. [Display omitted] • Rh–Ni(OH) 2 on nickel foam boosts hydrogen production at high current densities. • Lattice contraction in Ni(OH) 2 due to Rh improves HER activity. • Achieves industrial current density with low overpotentials (130 mV at room temperature, 67 mV at 80 °C). • Exceptional Stability: Maintains performance even after a 3-month test. [ABSTRACT FROM AUTHOR]

The demand for renewable energy sources has become more urgent due to climate change and environmental pollution. The oxygen evolution reaction (OER) plays a crucial role in green energy sources. This article primarily explores the potential of using non‐noble metals, such as transition and rare earth metals, to enhance the efficiency of the OER process. Due to their cost‐effectiveness and unique electronic structure, these non‐noble metals could be a game‐changer in the field. ′Doping,′ which is the process of adding a small amount of impurity to a material to alter its properties, and ′synergistic effects,′ which refer to the combined effect of two or more elements that is greater than the sum of their individual effects, are two key concepts in this field. Transition and rare earth metals can reduce the overpotential, a measure of the excess potential required to drive a reaction, thus enhancing the OER process by engineering the electronic and surface molecular structure. This article summarizes the roles of various non‐noble metals in the OER process and highlights opportunities for researchers to propose innovative ways to optimize the OER process. [ABSTRACT FROM AUTHOR]

Here we present the density functional theory-based exploration of layered IrO2 polymorphs for the oxygen evolution reaction, as well as a data-driven geometric descriptor for catalytic activity. The layer edges are identified as promising active site motifs with not only low theoretical overpotential but also intriguing structural flexibility and to break the universal energetic scaling through torsional distortion. [ABSTRACT FROM AUTHOR]

The precise regulation of single‐atom catalysts (SACs) with the desired local chemical environment is vital to elucidate the relationship between the SACs structure and the catalytic performance. The debate on the effect of the local coordination environment is quite complicated even for the SACs with the same composition and chemical nature, calling for increased attention on the regulation of the second coordination shell. For oxide‐supported SACs, it remains a significant challenge to precisely manipulate the second coordination shell of single atoms supported on oxides due to the structural robustness of oxides. Here, Ir single atoms were anchored on NiO supports via different bonding strategies, resulting in the diverse Ir−O−Ni coordination numbers for Ir sites. Specifically, Ir1/NiO, Ir1−NiO, and Ir1@NiO SACs with increasing Ir−O−Ni coordination numbers of 3, 4, and 5 were synthesized, respectively. We found that the activity of the three samples towards oxygen evolution reaction (OER) exhibited a volcano‐shaped relationship with the Ir−O−Ni coordination number, with Ir1−NiO showing the lowest overpotential of 225 mV at 10 mA cm−2. Mechanism investigations indicate that the moderate coordination number of Ir−O−Ni in Ir1−NiO creates the higher occupied Ir dz2 orbital, weakening the adsorption strength for *OOH intermediates and thereby enhancing the OER activity. [ABSTRACT FROM AUTHOR]

Metal‐organic frameworks (MOFs) have emerged as promising pre‐catalysts for oxygen evolution reaction (OER) due to their marvelous structural reconstruction process in strongly alkaline media. However, targeting design MOF structures to achieve excellent OER performance of reconstructed products is a challenge. Here, a strategic defect engineering is used to promote the OER performance of reconstructed products. Briefly, modified linkers with monocarboxylic acids (ferrocene carboxylic acid, FcCA) are incorporated into MOF (NiBDC‐FcCA), leading to its stepwise reconstruction into Fe‐doped Ni(OH)2 and NiOOH during the OER process, with the oxygen vacancy and strategic doping of metal Fe persisting throughout the multi‐step reconstruction. Benefiting from the synergistic interaction of oxygen vacancies and Fe doping, NiBDC‐FcCA delivers the extremely enhanced current density at 1.6 V versus reversible hydrogen electrode by ≈9 times compared with that of NiBDC. Moreover, the optimized NiBDC‐FcCA/Fe foam exhibits excellent OER catalytic activity and stability with a low overpotential of 250 mV at 200 mA cm−2 and negligible activity decay after 1200 h at 1 A cm−2. Density function theory calculations reveal that Fe doping weakens the interaction of oxygen intermediate with Ni sites, favoring the formation of OOH* to accelerate the OER process. [ABSTRACT FROM AUTHOR]

A novel Ir−Mn dual‐atom electrocatalyst is synthesized by a facile ion‐exchange method by incorporating Ir in SrMnO3, which yields an extremely high activity and stability for the oxygen evolution reaction (OER). The ion exchange process occurs in a self‐limitation way, which favors the formation of Ir−Mn dual‐atom in the IrMnO9 unit. The incorporation of Ir modulates the electronic structure of both Ir and Mn, thereby resulting in a shorter distance of the Ir−Mn dual‐atom (2.41 Å) than the Mn−Mn dual‐atom (2.49 Å). The modulated Ir−Mn dual‐atom enables the same spin direction O (↑) of the adsorbed *O intermediates, thus facilitating the direct coupling of the two adsorbed *O intermediates to release O2 via the oxygen‐oxygen radical coupling mechanism. Electrochemical tests reveal that the Ir‐SrMnO3 exhibits a superior OER's activity with a low overpotential of 207 mV at 10 mA cm−2 and achieves a mass specific activity of 1100 A gIr−1 at 1.5 V. The proton‐exchange‐membrane water electrolyzer with the Ir‐SrMnO3 catalyst exhibits a low electrolysis voltage of 1.63 V at 1.0 A cm−2 and a stable 2000‐h operation with a decay of only 15 μV h−1 at 0.5 A cm−2. [ABSTRACT FROM AUTHOR]

The synthesized RuO2/MnCo2O4.5 nano-heterostructure possesses dense interfaces and abundant defect structures, synergistically balancing oxygen evolution reaction (OER) activity and stability. RuO2/MnCo2O4.5 exhibits a low overpotential of 190 mV at 10 mA cm−2. The proton exchange membrane (PEM) electrolyzer assembled can operate at 200 mA cm−2 stably for 50 h. [ABSTRACT FROM AUTHOR]

The strategic formulation of a compatible electrolyte plays a pivotal role in extending the longevity of lithium‐metal batteries (LMBs). Here, we present findings on a partially fluorinated electrolyte distinguished by a subdued solvation affinity towards Li+ ions and a concentrated anion presence within the primary solvation layer. This distinctive solvation arrangement redirects the focal points of reactions from solvent molecules to anions, facilitating the predominant involvement of anions in the creation of a LiF‐enriched solid‐electrolyte interphase (SEI). Electrochemical assessments showcase effective Li+ transport kinetics, diminished overpotential polarization for Li nucleation (28 mV), and prolonged cycling durability in Li||Li cells employing the partially fluorinated electrolyte. When tested in Li||NCM811 cells, the designed electrolyte delivers a capacity retention of 89.30 % and exhibits a high average Coulombic efficiency of 99.80 % over 100 cycles with a charge‐potential cut‐off of 4.6 V vs. Li/Li+ under the current density of 0.4C. Furthermore, even at a current density of 1C, the cells maintain 81.90 % capacity retention and a high average Coulombic efficiency of 99.40 % after 180 cycles. This work underscores the significance of weak‐solvation interaction in partially fluorinated electrolytes and highlights the crucial role of solvent structure in enabling the long‐term stability and high‐energy density of LMBs. [ABSTRACT FROM AUTHOR]

The development of electrocatalysts is of vital importance to the OER. In this work, an optimized MOF electrode, Ir-NiFe-btz/NF, was synthesized by incorporating ultralow levels of Ir nanoparticles into an ionic bimetallic MOF. Under alkaline conditions, the prepared MOF electrode demonstrated outstanding OER activity and stability with a low overpotential of 182 mV to reach 10 mA cm−2 and no obvious increase of overpotential in a chronovoltammetry test over 100 hours at 100 mA cm−2. [ABSTRACT FROM AUTHOR]

Alkaline water electrolysis was performed using Ni(OH) 2 /NiOOH as an anode and MmNi 5 -based hydrogen storage alloy as a cathode removed from NiMH batteries at 303 K and 10 mA/cm2 for 2 h. The water decomposition voltage changed from 1.36 V to 1.48 V (thermoneutral voltage: 1.48 V). The hydrogen evolution reaction (HER) overpotentials of the practically used MmNi 5 -based alloy with low H 2 dissociation pressure 0.012 MPa were small (33–75 mV) at 10 mA/cm2. The HER overpotentials were similar to those of Pt-based electrocatalysts. The low dissociation pressure of the hydride was suggested to play a key role to decrease the HER overpotentials of the alloy. The alkaline water electrolysis voltage was 1.46–1.48V and stable at 50 mA/cm2 and 353K for 24h. Then, the MmNi 5 -based hydrogen storage alloy was found to be a new type of HER electrocatalyst for alkaline water electrolysis. [Display omitted] • Alkaline water electrolysis was performed using Ni(OH) 2 and MmNi 5 -based alloy. • HER overpotentials of the alloy with low dissociation pressure were 33–75 mV. • The overpotentials of the alloy were similar to those of Pt-based electrocatalysts. • The dissociation pressure of the alloy hydride increased with the overpotential. • The water electrolysis voltage was stable at 50 mA/cm2 and 353K for 24h. [ABSTRACT FROM AUTHOR]

NiFe-based oxyhydroxides are promising electrocatalysts for the oxygen evolution reaction (OER) in alkaline media, but further enhancing their OER performance remains a significant challenge. Herein, we in situ incorporated polyoxometalates into NiFe oxyhydroxides to form a homogeneous/heterogeneous hybrid material, which induces the electronic interaction between Ni, Fe and Mo sites, as revealed by a variety of characterization experiments and theoretical calculations. The resulting hybrid electrocatalyst delivers a low overpotential of 203 mV at 10 mA cm−2 and a TOF of 2.34 s−1 at 1.53 V in alkaline media. This work presents a critical step towards developing high-performance OER catalysts by constructing metal–POM hybrids. [ABSTRACT FROM AUTHOR]

FeNiOOH is regarded as the most stable active species in the oxygen evolution reaction (OER), but the high oxidation energy of NiOOH poses a challenge to directly synthesize FeNiOOH as a real OER catalyst. Herein, an anion‐mediated kinetically controlled strategy is proposed, coupled with cation‐induced geometric topology modulation, to directly synthesis FeNiOOH with ultra‐thin, densely packed nanosheet architectures. Specifically, the Cl−‐mediated in situ generation of hypochlorous acid promotes the direct formation of NiFeOOH. Concurrently, high‐valence competitive Ru3+ mitigate electrostatic repulsion, fostering a compact and densely packed assembly of Ru/FeNiOOH nanosheet branches. Furthermore, the intrinsic electron‐capturing ability of FeOOH, in synergy with the stabilizing effect of doped Ru atoms, further promote the formation and stabilization high‐valence NiOOH. Consequently, the hierarchical Ru/FeNiOOH@NiPOx nanoarray catalyst displays exceptional OER performance, with an overpotential of 172 mV at 10 mA cm−2 and outstanding stability. This study provides a novel strategy to directly construct a real catalyst. [ABSTRACT FROM AUTHOR]

Li─O2 batteries (LOBs) have the largest theoretical capacity among current batteries, but the irreversible growth and decomposition of Li2O2 products in positive electrodes cause dramatic degradation of their capacities over charging–discharging cycles. Herein, a metal–organic framework is reported with bipyridinic N linkers attached to graphene (bpyN‐MOF/g) as a positive electrode material to overcome the challenge. The bpyN‐MOF/g promotes conformal Li2O2 growth during discharging, while allowing Li2O2 decomposition at a low overpotential (0.487 V vs Li+/Li at 200 mA gc−1) during charging process, outperforming the Pt/C‐based electrode (0.857 V). Moreover, 3D‐tomography and density functional theory calculations consistently support the Li2O2 growth and decomposition mechanism inside bpyN‐MOF/g. Furthermore, bpyN‐MOF/g//Li LOBs achieve an exceptional discharge capacity (17 275 mAh gc−1 at 100 mA gc−1) and steady cycling for 270 cycles at 1000 mAh gc−1 under 2000 mA gc−1. Additionally, high gravimetric capacity at low mass loadings (0.27–0.44 mg cm−2) and stable cycle operation at a high areal current density (0.5 mA cm−2) open new opportunities for various practical applications. [ABSTRACT FROM AUTHOR]

The energy crisis stems from increasing demand, diminishing fossil fuel reserves, and insufficient investment in renewable alternatives, posing a profound threat to global energy security and environmental sustainability. Fuel cells offer promise as a solution to the energy crisis and the integration of two-dimensional carbon materials in fuel cell catalysts holds potential for enhancing efficiency, reducing costs, and improving the overall sustainability of fuel cell technologies. The new two-dimensional carbon form tetra-penta-octagonal-graphene and its boron doped derivative have been examined in this report for its applicability in the electrocatalytic oxygen reduction reaction for generation of electricity. The most favorable site for the reaction in the pristine specimen and the most favorable boron doping site have been carefully determined based on adsorption energy and formation energy, respectively. Projected density of states confirms a low density of states for the active site in both specimens. Boron doping causes a significant charge transfer from the primed site. The analysis of the four electron pathways along with the dioxygen adsorption step in the acidic medium has been conducted to gain a deeper understanding of the process. In both systems, the formation of the *O intermediate is associated with the highest Gibbs free energy change. The performance of the pristine material in the process has been found to support monotonically exothermic reaction with an overpotential of 0.622 V whereas the boron doped specimen presents very small barrier for the dioxygen adsorption step followed by monotonically exothermic reaction steps with overpotential 0.549 V. • A new sp2 stable 2D carbon allotrope TPO-graphene shows electrocatalytic activity. • Active site has lowest partial density of states at Fermi level. • Steps of ORR in four-electron pathway in acidic medium are monotonically exothermic. • TPO-graphene has a overpotential of 0.622 V for the ORR process. • Boron doping creates ORR catalysis site with lowest partial density of states. • Boron doped TPO-graphene has a overpotential of 0.549 V for the ORR process. [ABSTRACT FROM AUTHOR]

The meticulous design of heterogeneous interfaces presents a promising approach for enhancing the electrocatalytic activity of Cu-based materials in nitrate reduction reactions. Herein, we developed a self-templated metal–organic frameworks transformation strategy to synthesize hollow multi-metallic oxide materials with well-defined interfaces. By utilizing novel hollow Cu–Co bimetallic Prussian blue analogs as precursors, a hollow cage composed of ultra-small CuO/Co3O4 hetero-nanograins was successfully constructed. It was discovered that this structure greatly enhanced the electrocatalytic activity for the conversion of NO3− to NH3, achieving a remarkably high Faradaic efficiency (FE) for NH3 (with a maximum FE of 90.68%) at low overpotential ranges. Furthermore, electrochemical experiments and in situ spectroscopy provided evidence that electrochemically induced reconstruction led to the formation of synergistic sites between Cu and Co3O4. This enabled the sequential reduction of nitrate and nitrite on adjacent metal/metal oxide phases, resulting in the rapid generation of NH3. [ABSTRACT FROM AUTHOR]

Low ionic migration and compromised interfacial stability pose challenges for low‐temperature batteries. In this work, we discovered that even with the state‐of‐the‐art localized high‐concentration electrolytes (LHCEs), uncontrolled Na electrodeposition occurs with a huge overpotential of >1.2 V at −20 °C, leading to cell failure within tens of hours. To address this, we introduce a new electrolyte category that incorporates an ionic liquid as a key solvation species. Diverging from traditional LHCEs, the IL‐tailored LHCE facilitates an anion–solvent‐molecules exchange within the solvation sheath between Na+ and organic cations at low temperatures. This behavior reduces solvation cluster size and strengthens Na+–anion coordination, which proves instrumental in enabling fast ionic dynamics in both the bulk liquid and at the interface. Therefore, durable Na electrodeposition and shuttle‐free, 0.5 Ah sodium–sulfur pouch cells are achieved at −20 °C, for the first time, surpassing the limitations of typical LHCEs. This tailoring strategy opens a  new design direction for advanced batteries operating in fast‐charge and wide‐temperature scenarios. [ABSTRACT FROM AUTHOR]

As ammonia continues to gain more and more interest as a promising hydrogen carrier compound, so does the electrochemical ammonia oxidation reaction (AmOR). To avoid the liberation of H2 in a reverse Haber–Bosch reaction under release of the energetically more favorable N2, we propose the oxidation of ammonia to value‐added nitrite (NO2−), which is usually obtained during the Ostwald process. We investigated the anodic oxidation of gaseous ammonia directly supplied to a gas diffusion electrode (GDE) using a variety of compositionally different multi‐metal catalysts coated on Ni foam under the simultaneous formation of H2 at the cathode. This will double the amount of H2 per ammonia molecule while applying a lower overpotential than that required for water electrolysis (1.4–1.8 V vs. RHE at 50 mA ⋅ cm−2). A selectivity study demonstrated that some of the catalyst compositions were able to produce significant amounts of NO2−, and further investigations using the most promising catalyst composition Nif_AlCoCrCuFe integrated within a GDE demonstrated up to 88 % Faradaic efficiency for NO2− at the anode coupled to close to 100 % Faradaic efficiency for the cathodic H2 production. [ABSTRACT FROM AUTHOR]

A highly efficient electrocatalytic platform based on in situ formed metallic bismuth submicron crystals (microBi) was developed for 4-aminophenol electrosynthesis via the electrochemical reduction of 4-nitrophenol at acidic pH. The facile formation and high reactivity of microBi enable efficient electrosynthesis of 4-aminophenol with high selectivity (∼100%) at the expense of an ultra-low overpotential. [ABSTRACT FROM AUTHOR]

Facile preparation of low-cost electrocatalysts for an efficient oxygen evolution reaction (OER) is significant but remains a big challenge. Herein, a novel and facile strategy for transforming intrinsic non-stoichiometric ultrathin Co5(O9.48H8.52)NO3 nanosheets into oxygen-vacancy enriched Co3O4/CoOOH heterostructure nanosheets for an efficient OER was developed. The as-synthesized Co3O4/CoOOH heterostructure nanosheets displayed excellent OER performances, showing an extremely low overpotential of 260 mV at a current density of 10 mA cm−2, a relatively small Tafel slope of 52 mV dec−1, and a long-term durability of at least 20 h. This work provides a new way for the production of oxygen vacancies on metal (oxy)hydroxide nanosheets through electric-field assisted in situ transformation of non-stoichiometric metal oxyhydroxide nanosheets. [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]

Secondary non-aqueous magnesium-based batteries are a promising candidate for post-lithium-ion battery technologies. However, the uneven Mg plating behavior at the negative electrode leads to high overpotential and short cycle life. Here, to circumvent these issues, we report the preparation of a magnesium/black phosphorus (Mg@BP) composite and its use as a negative electrode for non-aqueous magnesium-based batteries. Via in situ and ex situ physicochemical measurements, we demonstrate that Mg ions are initially intercalated in black phosphorus two-dimensional structures, forming chemically stable MgxP intermediates. After the formation of the intermediates, Mg electrodeposition reaction became the predominant. When tested in the asymmetric coin cell configuration, the Mg@BP composite electrode allowed stable stripping/plating performances for 1600 h (800 cycles), a cumulative capacity of 3200 mAh cm−2, and a Coulombic efficiency of 99.98%. Assembly and testing of the Mg@BP | |nano-CuS coin cell enabled a discharge capacity of 398 mAh g−1 and an average cell discharge potential of about 1.15 V at a specific current of 560 mA g−1 with a low decay rate of 0.016% per cycle for 225 cycles at 25 °C. Uneven Mg plating behaviour at the negative electrode leads to high plating overpotential and short cycle life. Here, to circumvent these issues, authors report the preparation of a magnesium/black phosphorus composite and its use as a negative electrode for non-aqueous magnesium-based batteries. [ABSTRACT FROM AUTHOR]

Ensuring effective and controlled zinc ion transportation is crucial for functionality of the solid electrolyte interphase (SEI) and overall performance in zinc‐based battery systems. Herein the first‐ever demonstration of incorporate cation‐π interactions are provided in the SEI to effectively facilitate uniform zinc ion flux. The artificial SEI design involves the immobilization of 4‐amino‐p‐terphenyl (TPA), a strong amphiphilic cation‐π interaction donor, as a monolayer onto a conductive poly(3,4‐ethylenedioxythiophene) (PEDOT) matrix, which enable the establishment of a robust network of cation‐π interactions. Through a carefully‐designed interfacial polymerization process, a high‐quality, large‐area, robust is achieved, thin polymeric TPA/PEDOT (TP) film for the use of artificial SEI. Consequently, this interphase exhibits exceptional cycling stability with low overpotential and enables high reversibility of Zn plating/stripping. Symmetrical cells with TP/Zn electrodes can be cycled for more than 3200 hours at 1 mA cm−2 and 1 mAh cm−2. And the asymmetric cells can cycle 3000 cycles stably with a high Coulomb efficiency of 99.78%. Also, under the extreme conditions of lean electrolyte and low N/P ratio, the battery with TP protective layer can still achieve ultra‐stable cycle. [ABSTRACT FROM AUTHOR]

A systematic investigation of the electrochemical iron nitride synthesis in a LiCl/KCl salt melt at 723 K shows an optimum of ϵ -Fe 3 N 1 + x formation in the range of 2.2 to 2.3 V and for γ ′ -Fe 4 N between 2.4 and 2.5 V enabling the control of the desired iron nitride phase by setting the supplied terminal voltage. The product formation of iron nitrides starts when the electrochemical window is reached, which could be verified by linear sweep voltammetry. Hence, a maximum of nitrogen content in the formed iron nitride phases is observed for 2.27 V. During elongated synthesis periods, convection emerges as the predominant transport mechanism hindering an accelerated reaction rate with higher overpotential applied. Real-time analysis of the background current allows conclusions about the remaining nitride concentration. Additionally, there is concurrent iron nitride formation at the electrode surface through nitride adsorption and autonucleation-induced precipitation of iron and nitride ions. The analysis of the amount of sediment in comparison to the layer thickness of the nitrided working electrode suggests that the autonucleation mechanism dominates over the adsorption mechanism with increasing overpotential and can be further enhanced by this feature. [ABSTRACT FROM AUTHOR]

This article describes the relationship that relates the static threshold parameter of K1SCC (at ∼10−10 m/s) to ΔKth and Kmax,th (at ∼10−10 m/cycle) under fatigue load at high R-ratio like R = 0.85. At these high R-ratios (>0.75), applied Kmax > K1SCC and the fracture path has a larger component of static fracture. 5083 Al alloy is adapted as an example to demonstrate this relationship at room temperature their relationship with and without GB-β anodic precipitates in inert and a 3.5 % NaCl solution environments. We are interested in the mechanical cyclic ΔKth and Kmax,th and quasi-static KISCC driving forces affecting the damage in the presence of a chemical environment due to anodic dissolution of the GB-β precipitates. Detailed discussions involve how these parameters are interrelated. [ABSTRACT FROM AUTHOR]

Rechargeable aqueous zinc batteries (AZIBs) with merits of high safety and high theoretical capacity are regarded as next‐generation energy storage devices. However, their practical application is hindered by the instable Zn anodes associated with the dendrite growth, parasite corrosion and side reactions. Developing a stable solid electrolyte interface is crucial for improving the cycling stability of Zn anodes. Herein, a hydrophobic interface is constructed on Zn anode through a simple heptafluorobutyrate acid etching route. The hydrophobic interface containing organic C─F, O─C═O and inorganic Zn─F bonds effectively address the issues of dendrites growth and parasitic reactions. Consequently, symmetric cells with acid‐treated Zn‐HA anodes achieve a prolonged lifespan of over 2000 h at 4.0 mA cm−2 and 1100 h at 10.0 mA cm−2. When paired with MnO2 cathode, the full cells deliver lower overpotential and outstanding cycling stability. This strategy provides a simple and feasible method to construct stable Zn anode for achieving high performance AZIBs. [ABSTRACT FROM AUTHOR]

The 2D porous protonated NiSe/g-C 3 N 4 nanosheets are synthesized via a chemical-calcination-etching-acidification-hydrothermal method. The obtained 2D NiSe/g-C 3 N 4 nanosheets (NiSe/HCN-3) exhibit signally enhanced HER (∼1184.74 μmol g−1 h−1)/degradation (∼0.04645 min−1) than the monomer g-C 3 N 4 (∼150/5-folds), including a decent stability (average HER ∼1152.71 μmol g−1 h−1). It mainly attributes to the NiSe/g-C 3 N 4 interface owns appropriate potential gradient can promote the interface carrier driving to optimize efficiency, including increasing carrier transport, extending carrier lifetime, and reducing recombination, as well as the porous nanosheets and surface protonation obtain numerous active sites for decreasing overpotential and promoting electron solid/liquid interfacial diffusion. Additionally, the 2D porous nanosheets can improve the solar efficiency (multiple internal reflections) and shorten the carrier pathway. [Display omitted] • NiSe co-catalyst optimize carrier efficiency by appropriate Fermi level gradient. • Surface protonation increase active sites to promote electron interfacial diffusion. • Porous nanosheets increase active sites/solar efficiency and shorten carrier path. [ABSTRACT FROM AUTHOR]

Atomic isolated and dispersed single atom catalyst is ideal for high-performance industrial catalyst. However, the contribution from small amounts of nanoclusters coexisting with single atoms to the catalytic reaction activity is often neglected. In this work, a MXene-supported uniformly dispersed Pt single atoms and nanoclusters (Pt 1 +Pt n /MXene) were obtained by self-assembly through an impregnation method. The catalyst exhibits high electrochemical performance in the hydrogen evolution reaction with an overpotential of only 61.3 mV and a Tafel slope of 32.5 mV dec−1 at a current density of 10 mA cm−2 in an acidic environment. The XAFS analysis and further DFT calculation indicate that the synergistic effect between single atoms and nanoclusters can facilitate adsorption of H* and promote the HER reaction. This work provides an efficient method for integrating multiple active sites in noble metal catalysts. • Constructing Pt sites on MXene enables a strong synergism between nanoclusters and single atoms. • Pt 1 +Pt n /MXene possesses large numbers of highly active Ti–O–Pt interfacial sites. • Ti–O–Pt sites make Pt 1 +Pt n /MXene obtain an outstanding catalytic performance in HER. • Pt 1 +Pt n /MXene boosts the adsorption of H* and promotes the HER reaction process. [ABSTRACT FROM AUTHOR]

Developing an OER electrocatalyst that combines high performance with low cost represents a crucial challenge to address for the widespread adoption and implementation of PEM water electrolyzers. The Ru-based catalyst has garnered significant interest owing to its cost-effectiveness and high activity, positioning it as one of the prime contenders to replace Ir-based catalysts. Nevertheless, Ru-based catalysts are easily corrupted by oxidation at high potential, leading to poor catalyst durability. In this work, we used a simple method to synthesize an electrode material which was a carbon framework-supported coralline RuCo alloy catalyst on the CC surface. The porous and highly conductive carbon framework in RuCo@C/CC effectively anchors the RuCo alloy, preventing its aggregation and detachment from the CC. And the carbon framework also facilitates enhanced mass and charge transfer processes, thereby greatly improving catalytic performance. Additionally, charge transfer and redistribution occur within the RuCo alloy, thereby efficiently reducing the activation energy barrier (via the AEM mechanism) of the OER, consequently enhancing OER performance. Therefore, RuCo@C/CC exhibits outstanding performance in acidic OER, achieving a current density of 10 mA/cm2 at a remarkably low overpotential of 200 mV, significantly surpassing commercial RuO 2 (which requires 280 mV), owing to its exceptional OER kinetics, while also demonstrating exceptional stability in practical PEMWE test. This research introduces a convenient route for creating a highly efficient and durable alloy electrocatalyst, showcasing its promise for Proton Exchange Membrane Water Electrolysis. • Charge transfer and redistribution within RuCo reduce the OER energy barrier. • Role of C skeleton in preventing RuCo shedding and enhancing mass and charge transfer. • RuCo@C/CC shows a low overpotential of 200 mV at η 10 , surpassing commercial RuO 2. [ABSTRACT FROM AUTHOR]

The advancement of effective and robust catalysts that can replace the precious-metal-based benchmarks for electrocatalytic overall water splitting is a highly fashionable approach to exploring sustainable energy utilization and addressing environmental issues. Herein, we demonstrate a facile single-step fabrication of NiS-NiS 2 nanoparticles in situ grown on the layered porous sulfur-doped graphitic carbon nitride nanosheets (NiS-NiS 2 /SGCN) act as bifunctional electrocatalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in an alkaline medium. Further, an increasing the Ni precursor (fixed sulfur source) increases the formation of NiS-NiS 2 on the surface of SGCN (labeled as NS-1.0, NS-2.0, and NS-3.0). Structural and morphological studies such as PXRD, XPS, FTIR, HR-TEM, etc., revealed a uniform distribution of NiS/NiS 2 on the surface of S-g-C 3 N 4 nanosheets. The OER and HER activity of NiS-NiS 2 /SGCN nanohybrid were significantly enhanced by increasing the affinity of accessible surface-active edge sites, interfacial contact allows effective modification of electronic structure, high structural porosity, redox-active centers of Ni2+/Ni3+, and rich in sulfur vacancy. In addition, the enhancement of the exposure of the edge sites is improved by their attachment to a sulfur-doped g-C 3 N 4 framework. As a result, in the half-cell experiments, the NiS-NiS 2 /SGCN (NS-3.0) catalyst exhibited enhanced performance in both OER and HER, requiring an overpotential of 298 mV to reach 50 mA/cm2 for OER and −144 mV to reach 10 mA/cm2 for HER. Furthermore, the constructed electrolyzer using Ni-S 3.0 as the cathode and anode required a cell voltage of 1.66 V to yield 50 mA/cm2 in overall water splitting. This study may inspire the in-situ synthesis of different metal sulfides on SGCN to provide a unique interfacial approach for improving the performance of bifunctional non-precious electrocatalysts. NiS-NiS2/SGCN as Bifunctional Electrocatalysts for HER and OER in an alkaline medium. [Display omitted] • Single-step fabrication of NiS-NiS 2 grown insitu on sulfur-doped graphitic carbon nitride. • NiS-NiS 2 /SGCN/NF exhibited a low OER overpotential of 298 mV (at 50 mA/cm2). • NiS-NiS 2 /SGCN/NF showed a low HER overpotential of −144 mV (at 10 mA/cm2). • NiS-NiS 2 /SGCN/NF electrode acts as a bifunctional electrocatalyst in alkaline media. [ABSTRACT FROM AUTHOR]

N-doped WO3 anchored on porous carbon (N–WO3/PNC) was synthesized as an efficient oxygen reduction catalyst. The N doping reduced the overpotential of WO3 during oxygen reduction. N–WO3/PNC displayed a half-wave potential of 0.85 V. An N–WO3/PNC-based zinc–air battery displayed a high power density of 209.7 mW cm−2. [ABSTRACT FROM AUTHOR]

Different from "bottom–up" Zn plating/stripping, "top–down" Zn stripping/plating provides a new perspective to reinvent current aqueous Zn batteries (AZBs), yet related studies remain absent. Herein, a chelation‐induced solvation barrier remodeling strategy is initiated toward fast‐kinetics "top–down" Zn stripping/plating in original Zn2+‐free water‐lean organic electrolytes (WLOE) for durable Zn batteries. It is found that in WLOE, the initial Zn stripping kinetics of the Zn anode remarkably limits the "top–down" Zn stripping/plating. The intervention of multidentate chelant (2‐methoxyethylamine, MEA) in WLOE greatly lowers the solvation reorganization energy of in situ stripped Zn2+ from the Zn anode, enabling the fast‐kinetics "top–down" Zn stripping/plating. Spectral characterization and fitted overpotential‐reorganization energy correlation strongly confirm the underlying mechanism. As such, the Zn stripping/plating in the MEA‐mediated WLOE shows a 90‐fold‐enhanced current response, triple‐lowered overpotential, and 170‐fold‐prolonged cyclability (over 1700 h at 0.5 mA cm−2) of those in MEA‐free counterpart. The assembled Zn||LiFePO4 hybrid full cell in MEA‐regulated WLOE exhibits a distinct and high voltage plateau of 1.50 V and a low polarization voltage of 0.14 V, far surpassing those in conventional WLOE. This work opens a new avenue to break the kinetics bottleneck of Zn stripping/plating in WLOE for durable Zn batteries. [ABSTRACT FROM AUTHOR]

While cobalt-based oxides can function as OER catalysts under acidic conditions, challenges such as high overpotential and inadequate stability persist, demanding solutions to fulfill practical application demands. We utilized a rapid and efficient one-step molten salt method to synthesize LaMn-doped Co 3 O 4 supported on carbon cloth, with the aim of improving its OER activity and stability in acidic conditions. Subsequent characterization revealed that doping increased oxygen vacancies and lattice distortion within the spinel structure, while also altering the morphology of the catalyst surface, rendering it denser. In addition, the doping optimizes the electronic structure around cobalt, so that the electrons around oxygen are biased towards cobalt, which enhances the electrocatalytic activity of Co 3 O 4 and the stability of Co–O bonds. Ultimately, under 0.5 M H 2 SO 4 conditions, LaMn–Co 3 O 4 /CC exhibited superior OER activity and stability, displaying a lower overpotential of 370 mV at a current density of 10 mA cm−2 and maintaining stability for over 24 h, a notable enhancement compared to pure Co 3 O 4. • Rapid synthesis of LaMn-doped Co 3 O 4 particles by a one-step molten salt method. • Doping inhibits particle growth and markedly influences the material's microstructure. • The performance of co-doped sample was markedly improved in all prepared materials. • The synergy of the two metals improves the catalytic performance of the material. [ABSTRACT FROM AUTHOR]

The electrolysis of water is the key method for hydrogen production but the high overpotential necessitates electrocatalysts. Traditionally, Pt is used, but it is scarce and costly. Herein, MnCO 3 is unveiled as an electrocatalyst for the production of hydrogen. MnCO 3 is electrodeposited onto pencil graphite by chronoamperometric method and confirmed by XRD and vibrational spectroscopic studies. MnCO 3 electrodeposited for 15 min at 2 V demonstrates a good HER activity (overpotential of 123 mV to reach 10 mA cm−2) in 0.5 M H 2 SO 4 with a Tafel slope of 79 mV dec−1. In addition, MnCO 3 exhibited good stability during continuous operation (over 3000 cycles and 14 h). Though MnCO 3 requires higher overpotential than the benchmark catalyst (Pt/C) to reach 10 mA cm−2, it outperforms Pt/C at higher current density (≥75 mA cm−2) demonstrating that MnCO 3 could be used as an electrocatalyst to produce H 2 at a high rate from acidic medium. [Display omitted] • MnCO 3 is electrodeposited onto pencil graphite by chronoamperometry method. • MnCO 3 electrodeposited at 2 V demonstrates a good HER activity in 0.5 M H 2 SO 4. • MnCO 3 exhibits good stability (over 3000 cycles and 14 h of continuous operation). • MnCO 3 surpassed the performance of Pt/C at 100 and 200 mA cm−2 [ABSTRACT FROM AUTHOR]

In recent years, the electrocatalytic nitrogen reduction reaction (NRR) has attracted considerable attention as a promising method for ammonia synthesis. Currently, various diatomic catalysts (DACs) composed of metal and non-metal combinations have been studied and reported for the NRR. These catalysts have been proven the ability to lower the reaction overpotential and enhance its activity. Among them, DACs supported on two-dimensional nitride materials have been widely applied in the NRR. In this work, ten heteronuclear diatomic catalysts supported on nitrogen-doped graphene were constructed. The research results demonstrated that MoCrN 6 -G exhibited the best catalytic performance among these catalysts due to its lowest overpotential (0.45 V) and low desorption free energy (0.15 eV) of NH 3 , as well as a higher selectivity for NRR compared to the hydrogen evolution reaction. It is worth emphasizing that the d-band center (ε d) is considered as a descriptor for rapidly screening efficient NRR electrocatalysts, further guiding the rational design of catalysts. [Display omitted] • Construced ten stable nitrogen-doped graphene supported heteronuclear diatomic catalysts. • The MoCrN 6 -G catalyst exhibited the lowest overpotential (0.45 V) during the NRR. • NH 3 can easily dissociate from the MoCrN 6 -G catalyst surface due to a desorption free energy of only 0.15 eV. • The MoCrN 6 -G catalyst demonstrated inhibitory effects towards the HER and showed high thermodynamic stability. • The d-band center (ε d) can serve as a predictive descriptor for rapidly screening highly active NRR catalysts. [ABSTRACT FROM AUTHOR]

The activation of lattice oxygen oxidation mechanism (LOM) will endow iridium‐based electrocatalysts with desired acid‐available water oxidation activity, compared to the conventional adsorbate evolution mechanism (AEM). However, the inherent symmetric [IrO6] octahedra of commercial Ir‐based catalysts generally thermodynamically favor the AEM pathway contributing to the moderate water oxidation performance. Here, based on typical layered Ca2IrO4 (CIO) modeled materials, the d‐orbitals electron repulsion strategy is demonstrated, via constructing asymmetrically polarized Ir‒O‒Ru configuration in Ru‐CIO, to effectively activate the lattice oxygen participating in water oxidation process for decent oxygen‐related electrocatalytic activity. Specifically, a great increase of ≈700‐fold and ≈170‐fold in mass activity and turnover frequency, respectively, has been realized for the optimal Ru‐CIO electrocatalyst in an acid medium relative to the commercial IrO2 electrocatalysts, where a small overpotential of only 175 mV is required for achieving 10 mA cmgeo‒2. In situ X‐ray fine structure spectroscopies combined with in situ 18O‐ isotope‐labeled differential electrochemical mass spectrometry analyses reveal that desirable LOM has been boosted by the activated lattice oxygen and the flexible Ir(3+δ)+ active sites of asymmetric [IrO6] octahedra, which results in superior OER kinetics for Ir‐based oxide catalysts. [ABSTRACT FROM AUTHOR]

Perovskite oxides are promising catalysts for water oxidation. Herein, we constructed a Sr3CoFeWO9 triple perovskite with Co, Fe, and W atoms sharing octahedral positions. Thermally activated growth of an amorphous FeCoW oxyhydroxide layer on this perovskite pre-catalyst greatly enhanced the oxygen evolution reaction (OER) activities, reducing overpotential at 10 mA cm−2geo by 115 mV. This highlights the benefits of compositional design and structural reconstruction for efficient electrocatalytic materials. [ABSTRACT FROM AUTHOR]

Overall urea–water electrolysis has the potential to be employed in the purification of urea-containing wastewater and the production of hydrogen. However, the lack of cost-effective catalysts currently presents a significant obstacle to the further development of this technology. Through a simple template-directed selenium reaction in a novel type of highly active solution, an interface engineering strategy was designed to synthesize hollow CuSe nanocubes as an efficient bifunctional catalyst. The unique hollow CuSe nanocubes exhibit significant catalytic efficiency because of their larger electrolyte contact area and faster ion transport. In 1 M KOH with a 0.5 M urea electrolyte, CuSe/NF required an overpotential of 199 mV for HER and a potential of 1.38 V for UOR to achieve a current density of 10 mA cm−2. It can work stably for 24 h without significant degradation of activity at 10 mA cm−2, showing excellent durability and excellent stability. For overall urea–water electrolysis, it exhibits a remarkable activity with a low cell voltage of 1.61 V at 10 mA cm−2. Consequently, the design strategy of this unique hollow-structured CuSe provides a new insight to improve electrocatalytic performance and stability. [ABSTRACT FROM AUTHOR]

Chirality‐induced spin selectivity observed in chiral 2D organic–inorganic hybrid perovskite holds promise to achieve spin‐dependent electrochemistry. However, conventional chiral 2D perovskites suffer from low conductivity and hygroscopicity, limiting electrochemical performance and operational stability. Here, a cutting‐edge material design is introduced to develop a stable and efficient chiral perovskite‐based spin polarizer by employing fluorinated chiral cation. The fluorination approach effectively promotes the charge carrier transport along the out‐of‐plane direction by mitigating the dielectric confinement effect within the multi‐quantum well‐structured 2D perovskite. Integrating the fluorinated cation incorporated spin polarizer with BiVO4 photoanode considerably boosts the photocurrent density while reducing overpotential through a spin‐dependent oxygen evolution reaction. Furthermore, the hydrophobic nature of fluorine in spin polarizer endows operational stability to the photoanode, extending the durability by 280% as compared to the device with non‐fluorinated spin polarizer. [ABSTRACT FROM AUTHOR]

Electrocatalytic conversion of CO2 into formate is recognized an economically‐viable route to upgrade CO2, but requires high overpotential to realize the high selectivity owing to high energy barrier for driving the involved proton‐coupled electron transfer (PCET) processes and serious ignorance of the second PCET. Herein, we surmount the challenge through sequential regulation of the potential‐determining step (PDS) over Te‐doped Bi (TeBi) nanotips. Computational studies unravel the incorporation of Te heteroatoms alters the PDS from the first PCET to the second one by substantially lowering the formation barrier for *OCHO intermediate, and the high‐curvature nanotips induce enhanced electric field that can steer the formation of asymmetric *HCOOH. In this scenario, the thermodynamic barrier for *OCHO and *HCOOH can be sequentially decreased, thus enabling a high formate selectivity at low overpotential. Experimentally, distinct TeBi nanostructures are obtained via controlling Te content in the precursor and TeBi nanotips achieve >90 % of Faradaic efficiency for formate production over a comparatively positive potential window (−0.57 V to −1.08 V). The strong Bi−Te covalent bonds also afford a robust stability. In an optimized membrane electrode assembly device, the formate production rate at 3.2 V reaches 10.1 mmol h−1 cm−2, demonstrating great potential for practical application. [ABSTRACT FROM AUTHOR]

The reconstruction of local electronic states in Pt-O x is an effective strategy for balancing charge distribution and enhancing the intrinsic activity of noble metals. This study presents the use of highly porous and oxygen-rich activated bluecoke powders as a desirable carbon support, and regulates Pt-O x bonds by incorporating the Fe as transition metal, leading to the development of an efficient bluecoke-based electrocatalyst characterized (Fe/Pt–O@MKABC) by exceptionally low Pt loading. The loading amount of Pt in Fe/Pt–O@MKABC is only 0.98 wt%, which is less than the 5% reported for commercial Pt/C catalyst, yet its hydrogen evolution performance is comparable. The developed catalyst presents exciting catalytic ability with overpotential of only 17 mV at 10 mA/cm2, a high mass activity of 8.3 A/(cm2·mg pt) at 50 mV, a large turnover frequency of 8.29 H 2 /s, and outstanding durability with a mere increase of 5 mV over 10000 cycles in acidic electrolyte. Detailed spectroscopic analysis and theoretical calculation results demonstrate that the abundant oxygen on activated bluecoke powders provides an opportunity for the construction of Fe-O y and Pt-O x. The introduction of Fe leads to electron rearrangement in Fe/Pt–O@MKABC, promoting electron transfer and reducing the adsorption free energy of H*, and the interaction between Fe-O y and Pt-O x enhances the hydrogen evolution reaction (HER) performance. [Display omitted] • Utilizing highly porous and oxygen-rich activated bluecoke powders as defect carbon support. • The introduction of Fe optimizes the Pt-O x bonds and significantly reduces the Pt loading. • The loading amount of Pt in the developed Fe/Pt–O@MKABC electrocatalyst is only 0.98 wt%. • The interaction between Fe-O y and Pt-O x accelerates the Volmer-Heyrovsky process. [ABSTRACT FROM AUTHOR]

The complete anodic oxidation of ammonia is an important part of direct ammonia fuel cells. Fabricating a high-performance electrocatalyst for ammonia oxidation reaction is meaningful for developing a direct ammonia fuel cell. Herein, we designed one platinum-decorated NiCo-layered double hydroxide nanoflower on Ni foam (Pt-NiCo-LDH-Ni foam) and measured the electrocatalytic performance via the cyclic voltammetry (CV) technique. The experimental results demonstrated that the optimized Pt-NiCo-LDH-Ni foam showed great electrocatalytic performance, with a low overpotential with a value of −0.573 V, a high current density of 17.75 mA cm−2 for the ammonia oxidation reaction, and good stability. [ABSTRACT FROM AUTHOR]

In order to deeply understand the multi-physical field coupling behavior inside the LIB(Lithium-Ion Battery) and better provide reference for the manufacturing and optimization design of the LIB, a more physically realistic coupled ETM(Electrochemical-Thermal-Mechanical) model of the LIB is established and solved in the finite element simulation software COMSOL Multiphysics by means of numerical simulation in the present study. The model takes into account the stress generation in both electrode and particle scales during battery operation, which solves the problem of difficult calculation of stress at the electrode level in previous models, and better correlates the relationship between stress and electrochemistry by considering the correction of stress on lithium diffusion and overpotential. Based on this model, the effect of different positive electrode particle sizes on the battery performance is discussed in the study. The numerical results show that the performance index of each physical field during the discharge of LIB is better and the energy density of the battery is improved when the positive electrode particle size is small, which proves that the use of smaller positive electrode particle size can improve the performance of LIB. [ABSTRACT FROM AUTHOR]

The electrocatalytic performance of a Fe65Co10Si12.5B12.5 Fe-based compounds toward alkaline hydrogen evolution reaction (HER) is enhanced by dealloying. The dealloying process produced a large number of nanosheets on the surface of NS-Fe65Co10Si12.5B12.5, which greatly increased the specific surface area of the electrode. When the dealloying time is 3 h, the overpotential of NS-Fe65Co10Si12.5B12.5 is only 175.1 mV at 1.0 M KOH and 10 mA cm−2, while under the same conditions, the overpotential of Fe65Co10Si12.5B12.5 is 215 mV, which is reduced. In addition, dealloying treated electrodes also show better HER performance than un-dealloying treated electrodes. With the increase in Co doping amount, the overpotential of the hydrogen evolution reaction decreases, and the hydrogen evolution activity is the best when the addition amount of Co is 10%. This work not only provides a basic understanding of the relationship between surface activity and the dealloying of HER catalysts, but also paves a new way for doping transition metal elements in Fe-based electrocatalysts working in alkaline media. [ABSTRACT FROM AUTHOR]

Previous studies have shown that partially coating electrode surfaces with patterns of 'islands' of hydrophobic tetrafluoroethylene (PTFE; Teflon) may lead to more energy efficient gas generation. This occurred because the gas bubbles formed preferentially on the PTFE, thereby freeing up the catalytically active metallic surfaces to produce the gas more efficiently. This work examined electrochemically induced hydrogen bubble formation on a nickel electrode surface that had been coated with linear patterns of PTFE. The impact of the PTFE line size (width) and degree of coverage was examined and analyzed. No improvement in electrical energy efficiency was observed up to 15 mA/cm2 when comparing the PTFE-coated electrodes with the control bare uncoated electrode. However, increasing PTFE coverage up to 15% generally improved electrolysis performance. Moreover, samples with 50% wider lines performed better (at the equivalent PTFE coverage), yielding an overpotential decline of up to 3.9% depending on the PTFE coverage. A 'bubble-scavenging' phenomenon was also observed, wherein bubbles present on the PTFE lines rapidly shrunk until they disappeared. [ABSTRACT FROM AUTHOR]

The accurate representation of lithium plating and aging phenomena has posed a persistent challenge within the battery research community. Empirical evidence underscores the pivotal role of cell structure in influencing aging behaviors and lithium plating within lithium‐ion batteries (LIBs). Available lithium‐ion plating models often falter in detailed description when integrating the structural intricacies. To address this challenge, this study proposes an innovative hierarchical model that intricately incorporates the layered rolling structure in cells. Notably, our model demonstrates a remarkable capacity to predict the non‐uniform distribution of current density and overpotential along the rolling direction of LIBs. Subsequently, we delve into an insightful exploration of the structural factors that influence lithium plating behavior, leveraging the foundation laid by our established model. Furthermore, we easily update the hierarchical model by considering aging factors. This aging model effectively anticipates capacity fatigue and lithium plating tendencies across individual layers of LIBs, all while maintaining computational efficiency. In light of our findings, this model yields novel perspectives on capacity fatigue dynamics and local lithium plating behaviors, offering a substantial advancement compared to existing models. This research paves the way for more efficient and tailored LIB design and operation, with broad implications for energy storage technologies. [ABSTRACT FROM AUTHOR]

The effect of structure of organic additives on the electrodeposition behavior of Zn from alkaline zincate solution and its crystal morphology was investigated. Zn was electrodeposited on an Fe electrode at 20-1000 A·m-2, 2.4 x 104 C·m-2, 300K from unagitated zincate solutions containing the various organic additives as a leveling agent. The suppression effect of additives on the charge transfer and diffusion of ZnO22- ions in Zn electrodeposition corresponded to the number of adsorption site per a straight chain molecule of polymer. The effect of polymer alone on the decrease in size of Zn platelets crystals was small, but the crystal size significantly decreased with coexistence of low molecular additive. The crystal size of deposited Zn decreased in spite of small suppression effect on Zn deposition, showing that the crystal size of deposited Zn doesn't depend on the overpotential for deposition. With coexistence of low molecular additive with polymer, the crystal of deposited Zn was fine regardless of kind of polymer even though Zn deposited at the diffusion control of ZnO22- ions. [ABSTRACT FROM AUTHOR]

This study explores the functionality of α‐Bi2Mo3O12 (BMO) as an electrocatalyst for water splitting and its suitability for supercapacitor applications. BMO was synthesized by the solvothermal method and characterized in pre‐calcination [BMO (BC)], post‐calcination [BMO (AC)], and base‐etched forms [BMO (BE)]. Structural analysis confirmed the formation of α‐Bi2Mo3O12 with well‐defined crystallographic planes. Electrochemical analysis revealed that BMO (AC) exhibited the lowest overpotential for hydrogen evolution reactions (HER) and BMO (BC) exhibited the lowest overpotential for oxygen evolution reactions (OER), indicating its superior electrocatalytic activity. The Tafel slope and electrochemical impedance spectroscopy results confirmed the superior kinetics and charge transfer properties of BMO material. Furthermore, BMO samples demonstrated excellent stability during prolonged chronoamperometry (CA) testing for 12 h. For supercapacitor performances, the BMO (BE) exhibits a superior specific capacitance value of 398 F/g at 2.0 A/g. Thus, the BMO material delivers prominent electrocatalytic activity as well as supercapacitor performance. Overall, this study demonstrates the potentiality of α‐Bi2Mo3O12 in different forms as a dual‐functional material for efficient energy storage and conversion. [ABSTRACT FROM AUTHOR]

Oxygen evolution reaction (OER) over perovskite oxides, upon undergoing a lattice oxygen oxidation mechanism, is strongly oxygen vacancy‐correlated as determined by the oxygen ion diffusivity. Despite substantial efforts having been devoted to tuning the oxygen vacancy concentration in perovskite oxides, the impact of the concomitant altering of oxygen vacancy ordering is often underestimated. In particular, the underlying mechanism of how the ordering and the concentration of oxygen vacancy affect the lattice OER, and how to well balance them still remain inadequately understood. Herein, a series of Sr1−xCaxCo0.5Fe0.5O3−δ with gradually increased oxygen vacancy concentration and ordering are synthesized. Theoretical calculations indicated that a higher oxygen vacancy concentration promoted the lattice oxygen migration, whereas a higher oxygen vacancy ordering impeded it. Particularly, Sr0.5Ca0.5Co0.5Fe0.5O3−δ with a relatively higher oxygen vacancy concentration and a lower ordering displayed the maximum oxygen diffusion rate and the optimal OER activity, affording a current density of 10 mA cm−2 at a quite low overpotential of 310.2 mV, together with a small Tafel slope of 55.87 mV dec−1. This study sheds light on the critical influence of oxygen vacancy configuration on the lattice OER, and paves a compromised avenue to screen and design advanced electrocatalysts for various electrochemical devices. [ABSTRACT FROM AUTHOR]

In this contribution, the design of a graphene-supported high-entropy single-atom catalyst (HESAC) composed of Fe, Co, Ni, and Ru metal atoms (FeCoNiRu-HESAC) is proposed. Negative formation energy and positive dissociation potentials indicate such materials' thermodynamic and electrochemical stability. Based on density functional theory (DFT) calculations, Co active sites lead to the overpotentials of 0.28 V RHE for oxygen evolution reaction (OER), 0.16 V RHE for hydrogen evolution reaction (HER), and 0.25 V RHE for CO 2 reduction reaction (CO 2 RR) towards CO formation. These surpass the activity of CoN 4 single-atom catalyst. More interestingly, the low CO 2 RR and HER overpotentials enable the FeCoNiRu-HESAC to produce syngas (CO + H 2). In addition, the Fe, Ni, and Ru sites simply serve as counterparts to modify the performance of Co active sites through non-bonding interactions. Besides, machine learning (ML) implies that, the valence electrons of intermediates as well as the d orbital electrons of metal sites are the most important parameters affecting the reaction intermediates' Gibbs free energy. According to these DFT and ML results, a strategy to design multifunctional HESACs electrocatalysts is developed. [Display omitted] • DFT calculations performed on multifunctional FeCoNiRu-HESAC species. • FeCoNiRu-HESAC surpassed the OER, HER, and CO 2 RR activities of SAC. • Fe, Ni, and Ru served as counterparts enhancing OER, CO 2 RR, and HER activity of Co. • Low HER- and CO 2 RR-overpotentials enabled the FeCoNiRu-HESAC to produce syngas. • ML implied valence e− of intermediates & d orbital e− of catalyst active site as the key parameters. [ABSTRACT FROM AUTHOR]