Hydrogen Reduction Reaction Research Articles

Construction of 0-dimensional silver quantum dot/MoSe2@MXene/3-dimensional porous copper foam composite electrodes with heterogeneous interfaces for synergistic electrocatalytic degradation of antibiotics

This study proposes a novel and efficient Ag quantum dots (QDs)/MoSe2@two-dimensional transition metal carbide/nitride (MXene)/copper foam (CF) composite electrode to address the challenge of electrocatalytic degradation of antibiotics in water. The electrode formed a unique electron donor–acceptor system by loading Ag QDs and heterostructured nanosheets on CF, significantly facilitating charge transfer and segregation at the interface. The catalytically active sites at the edges and defective locations of MoSe2 in conjunction with the two-dimensional MXene structure, which formed an efficient electron transfer channel, promoted the electron transfer from the interior to the surface and accelerated the hydrogen adsorption and reduction reactions. Moreover, the charge redistribution at the interface of Ag QDs and MoSe2@MXene formed interfacial dipoles, increasing the active sites on the catalyst surface and promoting the generation of cathodic atomic hydrogen (H*). Under optimal conditions, the degradation rate of tigecycline (TGC) reached as high as 90.1 % ± 2.4 % within 60 min. The anode-generated OH and HClO, along with the cathode-generated H, further promoted the degradation of TGC through co-catalysis. The degradation pathways were analyzed using density-functional theory (DFT) calculations and liquid chromatography-mass spectrometry (LC-MS) techniques. Moreover, toxicity analysis of the degradation products was carried out to ensure the safety of the treated wastewater discharge. A reflux continuous effluent reactor was also designed to achieve high degradation efficiency and low energy consumption after stable operation, laying the foundation for industrial applications. This technology provides new ideas for the design of green, efficient, stable, and low-consumption electrocatalytic reactors and contributes to a sustainable future environment.

Synergistic advancements in battery-grade energy storage: Nb2C/MoTe2(PANI) hybrid electrode material as a enhanced electrocatalyst for hydrogen reduction reaction

The inherent stratified arrangement, narrow energy band gap, and similar electrical conductivity of two-dimensional (2D) molybdenum ditelluride (MoTe2) have attracted considerable interest for their use in supercapacitors. Integrating Niobium Carbide (Nb2C) into the MXene framework significantly improves self-aggregation and electrochemical activity. The current work, Nb2C/MoTe2 was synthesized via a cost-effective and simple hydrothermal technique. However, the Nb2C/MoTe2 nanocomposite shows pronounced self-stacking problems during electrode fabrication, which can significantly restrict the capacity for storing charge. PANI was incorporated as a dopant to address these challenges and enhance electrochemical activity, such as Nb2C/MoTe2(PANI). The performance of supercapacitors was assessed by electrochemical measurement in an aqueous electrolytic solution with a concentration of 2 M potassium hydroxide (KOH). Based on the GCD profile, the Nb2C/MoTe2(PANI) material demonstrates a notable specific capacity (Qs) of 270 C/g, energy density of 72.2 Wh/kg, and power density of 935 W/kg at a current density of 2 A g-1. In contrast, the composite material demonstrates a specific capacity of 185 C/g, as proven by CV conducted at 5 mV/s. In addition, the nanohybrid has a high level of capacitance retention of 87.6 % after undergoing 8500 consecutive cycles. The exceptional efficiency of supercapacitor applications can be ascribed to the enhanced mechanical flexibility, active cooperation, and synergistic impacts of Nb2C/MoTe2 and PANI. The Nb2C/MoTe2(PANI) nanocomposite possesses significant potential for eco-friendly energy generation and allows for a simple single-step fabrication procedure. Consequently, it can serve as an electrode for highly efficient supercapacitors.

Continuous synthesis of metal oxide‐supported high‐entropy alloy nanoparticles with remarkable durability and catalytic activity in the hydrogen reduction reaction

AbstractMetal oxide‐supported multielement alloy nanoparticles are very promising as highly efficient and cost‐effective catalysts with a virtually unlimited compositional space. However, controllable synthesis of ultrasmall multielement alloy nanoparticles (us‐MEA‐NPs) supported on porous metal oxides with a homogeneous elemental distribution and good catalytic stability during long‐term operation is extremely challenging due to their oxidation and strong immiscibility. As a proof of concept that such synthesis can be realized, this work presents a general “bottom‐up” l ultrasonic‐assisted, simultaneous electro‐oxidation–reduction‐precipitation strategy for alloying dissimilar elements into single NPs on a porous support. One characteristic of this technique is uniform mixing, which results from simultaneous rapid thermal decomposition and reduction and leads to multielement liquid droplet solidification without aggregation. This process was achieved through a synergistic combination of enhanced electrochemical and plasma‐chemical phenomena at the metal–electrolyte interface (electron energy of 0.3–1.38 eV at a peak temperature of 3000 K reached within seconds at a rate of ~105 K per second) in an aqueous solution under an ultrasonic field (40 kHz). Illustrating the effectiveness of this approach, the CuAgNiFeCoRuMn@MgO‐P3000 catalyst exhibited exceptional catalytic efficiency in selective hydrogenation of nitro compounds, with over 99% chemoselectivity and nearly 100% conversion within 60 s and no decrease in catalytic activity even after 40 cycles (>98% conversion in 120 s). Our results provide an effective, transferable method for rationally designing supported MEA‐NP catalysts at the atomic level and pave the way for a wide variety of catalytic reactions.image

Synergistically-mediated highly-efficient visible-light-driven hydrogen evolution activity using Ohmic/Schottky-type dual-junctions and sulfur vacancy

Enabling highly-efficient multiplex-optimization photocatalysts is critical to overcome the bottlenecks of hydrogen evolution reaction efficiency and photostability. Herein, novel CoS/Sv-ZnIn2S4/MoS2 composites are successfully synthesized through an in situ technique. Taking advantage of the synergistic effect of sulfur vacancy, Schottky-type MoS2/Sv-ZnIn2S4 junction and Ohmic-type CoS/Sv-ZnIn2S4 junction, the light absorption, electron/hole separation efficiency, charge transfer rate and hydrogen reduction reaction dynamic can be significantly enhanced. As a result, an impressive photocatalytic hydrogen evolution rate of 18.43 mmol g−1 h−1 is achieved under the visible-light irradiation. Furthermore, apparent quantum efficiencies of 72.14 % and 9.91 % are also achieved under 350 and 420 nm monochromatic light irradiation. This work presents an in situ perspective to design multiplex-optimization photocatalytic system for highly-efficient hydrogen production.

Mitigating Side Reactions in Electrocatalytic Ammonia Synthesis by Nitrate Reduction

Electrocatalytic nitrate reduction holds significant promise for generating green ammonia and mitigating pollution, reducing energy input, and exhibiting zero-carbon emissions. However, the intricate multiple electron and proton transfer processes complicate the pathways from nitrate to ammonia, hindering the development of electrocatalysts with high activity and selectivity for practical use. The primary side reactions, such as the conversion of nitrate to gaseous nitrogen species and the hydrogen reduction reaction, limit the Faradaic efficiency of nitrate-to-ammonia conversion. In this work, we have developed a controllable methodology for preparing highly active Cu-based nanocatalysts. These nanocatalysts exhibit remarkable activity and selectivity in the electrochemical nitrate reduction reaction within a flow-cell device, with a high ammonia yield and high Faradaic efficiency.

Theoretical Calculation Assisted by Machine Learning Accelerate Optimal Electrocatalyst Finding for Hydrogen Evolution Reaction

AbstractElectrocatalytic hydrogen evolution reaction (HER) is a promising strategy to solve and mitigate the coming energy shortage and global environmental pollution. Searching for efficient electrocatalysts for HER remains challenging through traditional trial‐and‐error methods from numerous potential material candidates. Theoretical high throughput calculation assisted by machine learning is a possible method to screen excellent HER electrocatalysts effectively. This will pave the way for high‐efficiency and low‐price electrocatalyst findings. In this review, we comprehensively introduce the machine learning workflow and standard models for hydrogen reduction reactions. This mainly illustrates how machine learning is used in catalyst filtration and descriptor exploration. Subsequently, several applications, including surface electrocatalysts, two‐dimensional (2D) electrocatalysts, and single/dual atom electrocatalysts using machine learning in electrocatalytic HER, are highlighted and introduced. Finally, the corresponding challenge and perspective for machine learning in electrocatalytic hydrogen reduction reactions are concluded. We hope this critical review can provide a comprehensive understanding of machine learning for HER catalyst design and guide the future theoretical and experimental investigation of HER catalyst findings.

A comprehensive comparison of plastic derived and commercial Pt/C electrocatalysts in methanol oxidation, hydrogen evolution reaction, oxygen evolution and reduction reaction

This work utilized an innovative and economical remediation method to convert inexpensive waste feedstock into extremely useful catalysts. The procedure centered on polyethylene (PE), an easily accessible substance, and effectively transformed it at a mild temperature utilizing a new solvothermal technique, which entailed the reaction of sulfuric acid with PE chains at 120 °C. Throughout this process, the polymer experienced a pivotal cross-linking stage, resulting in its conversion into carbon materials when exposed to temperatures above 500 °C. To improve the catalytic characteristics, platinum (Pt) was effectively integrated into the resultant carbon matrix using the existing impregnation technique. Further, the catalyst's physicochemical properties were thoroughly analyzed utilizing SEM, FTIR, and XRD techniques. After that, the catalyst's performance was thoroughly evaluated in several electrocatalytic reactions, such as methanol oxidation, oxygen evolution and reduction reactions, and hydrogen evolution. The results of this investigation reveal the impressive electrocatalytic ability of the Pt/C catalyst made from waste plastic. It was found to be comparable to the best commercially available Pt/C catalysts in all the reactions that were examined. This research not only demonstrates the possibility of using waste plastic for catalyst production, but also serves as the first documented example, based on successfully converting waste plastic bags into Pt/C through the conventional Liquid Phase Reduction (LPR) process. This novel method has great potential for sustainable and ecologically responsible catalytic applications.

Multiobjective‐Optimization MoS2/Cd‐ZnIn2S4/CdS Composites Prepared by In Situ Structure‐Tailored Technique for High‐Efficiency Hydrogen Generation

Photocatalytic water splitting into hydrogen production provides a new avenue to produce clean chemical fuels. However, developing high‐efficiency photocatalytic materials still remains a challenge till now. Herein, multiobjective‐optimization MoS2/Cd‐ZnIn2S4/CdS (MS/CZIS/CS) composites are successfully constructed by an in situ structure‐tailored technique. Benefiting from the synergistic feature integrating sulfur vacancy, II‐type CZIS/CS heterojunction and Schottky‐type MS/CS heterojunction, such composites not only effectively steer photogenerated carrier transfer but also markedly expedite surface reaction kinetics for hydrogen reduction reaction. As a result, an optimal hydrogen evolution rate of 11.49 mmol g−1 h−1 is achieved over the MS/CZIS/CS catalysts, which is approximately 4.79 times higher than that of pristine ZIS (2.40 mmol g−1 h−1). This work provides some new inspirations for the steering of carrier transfer and the design of multiobjective‐optimization photocatalysts with high efficiency.

Tailoring photocatalytic water splitting activity of boron-thiophene polymer through pore size engineering.

Taking into account the electron-rich and visible light response of thiophene, first-principles calculations have been carried out to explore the photocatalytic activity of donor-acceptor polymers incorporating thiophene and boron. Honeycomb-kagome boron-thiophene (BTP) polymers with varying numbers of thiophene units and fixed B center atoms are direct bandgap semiconductors with tunable bandgaps ranging from 2.41 to 1.88eV and show high absorption coefficients under the ultraviolet and visible regions of the solar spectrum. Fine-tuning the band edges of the BTP polymer is efficiently achieved by adjusting the pore size through the manipulation of thiophene units between the B centers. This manipulation, achieved without excessive chemical functionalization, facilitates the generation of an appropriate quantity of photoexcited electrons and/or holes to straddle the redox potential of the water. Our study demonstrates that two units between B centers of thiophene in BTP polymers enable overall photocatalytic water splitting, whereas BTP polymers with larger pores solely promote photocatalytic hydrogen reduction. Moreover, the thermodynamics of hydrogen and oxygen reduction reactions either proceed spontaneously or need small additional external biases. Our findings provide the rationale for designing metal-free and single-material polymer photocatalysts based on thiophene, specifically for achieving efficient overall water splitting.

Investigations of the relationships between structure and electrochemical properties of fullerenol nanoaggregates

Hybrid materials containing fullerenols have been used as electrodes in many applications, such as electrochemical biosensors for different targets or in hydrogen and oxygen reduction reactions. However, electrodes modified with fullerenols and without other electroactive materials are not much explored, and the electrochemical behavior of fullerenols themselves is not well-established in the literature. Herein, we report the basic electrochemical characterization of electrode modified with fullerenol and some correlations between material structure and electrochemical behavior. The prepared fullerenol is composed of nanoaggregates dispersed in an organic solvent. Although the electrode modified with pristine fullerene is slightly less active to [Fe(CN)6]3−/4− concerning bare glassy carbon electrode (GCE), the fullerenol-based electrode presents a much lower activity that is slightly increased after electrochemical reduction. The drying process greatly influences the electrochemical performance of the electrodes modified with fullerenol, and fast drying can form ruptures with micrometric dimensions that provide a particular behavior towards the anionic probe. The reduction process increases the number and sizes of these ruptures and changes the electrochemical response. Moreover, the fullerenol-based electrode is more active for [Ru(NH3)6]3+ than the bare GCE, and the activity was increased after reduction. However, the electrochemical response to the cationic probe is characteristic of macroelectrodes regardless of the drying process or reduction. This work opens new perspectives in the electrochemical studies of modified carbon nanomaterials, with the possibility of producing carbon-based electrodes selective to charged probes by controlling the carbon materials' molecular and microscale structures.

Engineering hydrophobicity and high-index planes of gold nanostructures for highly selective electrochemical CO2 reduction to CO and efficient CO2 capture

In current study, we demonstrate a strategy for improving the catalytic performance of gold (Au) for carbon dioxide reduction reaction (CO2RR), specifically enhancing selectivity for CO over hydrogen evolution reaction (HER) and increasing low-level CO2 capture efficiency. This involved controlling nanostructures without any further modification. Au nanostructures having four different morphologies (i.e., degree of roughness) were fabricated via electrodeposition at varied deposition potential, resulting in different intrinsic surface hydrophobicity and exposure of high-index planes depending on the actual morphology. The roughest Au, with its combination of the most hydrophobic feature and abundant high-index planes, generated greater partial current density (jCO) and faradaic efficiency for CO (FECO) than the other Au deposits within a tested potential region: The roughest Au showed 6-fold higher FECO (95.8 %) and 327-fold higher jCO (normalized to electrode geometric surface area) at −0.75 VRHE compared to the smoothest Au. Moreover, the roughest Au exhibited excellent CO2 capture ability even at low CO2 concentration, confirmed with scanning electrochemical microscopy. These improvement at hierarchical Au for CO2RR could be ascribed to two factors. Firstly, the morphology-driven hydrophobicity provides an optimal gas–liquid-solid triple-phase interfaces, increasing the local CO2 concentration near the Au catalyst surface due to its superb CO2 capture ability. Secondly, the abundant high-index planes serve as stable active sites for CO2RR, expediting the reaction rates. Remarkably, Au with the highest hydrophobicity and enriched high-index planes, even without any chemical modification, showed excellent CO2RR catalytic performance comparable to or even better than the other previously reported Au-based catalysts.

Electronic structure and defect density co-modulation of CoSe2/CeO2 nanocomposite for bifunctional hydrogen oxidation and reduction reactions

Developing bifunctional non-precious metal electrocatalysts toward hydrogen oxidation reaction (HOR) and hydrogen evolution reaction (HER) in acid is seriously challenged in various applications, such as hydrogen purifiers, fuel cells, and water electrolyzers. Here, we report the development of CoSe2/CeO2 nanocomposite electrocatalyst improved by electrochemical tuning for efficient HOR and HER in acid. Electrochemical tuning is shown to generate Ce3+, Co3+, and oxygen vacancies on the surface of the nanocomposite, which are considered as active sites for the adsorption and desorption of hydrogen species. The tuned catalyst (t-CoSe2/CeO2) indicates an impressive activity towards HOR and HER in 0.5 M H2SO4 solution, achieving an anodic current density of 1.8 mA cm−2 at 900 rpm and cathodic overpotential of 61 mV, respectively, outperforming the commercial Pt/C. Besides, the synthesized electrocatalyst delivers favorable HOR/HER durability. Our results suggest that the surface manipulation of CoSe2/CeO2 nanocomposite could provide promising insights for substituting precious electrocatalysts for HOR/HER.

Research on V2O3 preparation by stepwise catalysis solution-phase hydrogen reduction from shale V-rich solution

Solution-phase hydrogen reduction reaction (SpHR) was introduced to overcome the problems of ammonia nitrogen pollution, high energy consumption, and long production flow of traditional reduction roasting. From φ-pH diagram, the increase of reaction temperature, vanadium concentration and H2 partial pressure is beneficial to the preparation of V2O3. High purity V2O3 could not be prepared by single addition catalysis and synchronous catalysis in SpHR process, and the Ni + NiSO4 stepwise catalysis can effectively eliminate the problem of nickel wrapped in vanadium precipitates during the precipitation process. Under the optimal conditions of Ni + NiSO4 stepwise catalysis of nickel powder dosage 5 g/L, NiSO4 dosage 8 g/L, nickel powder catalytic time 90 min, NiSO4 catalytic time 30 min, the precipitate with nickel content 11.15 % was obtained, and Ni catalyst can be separated by magnetic separation with nickel recovery ratio of 99.52 %. Ni2+ in SpHR precipitates to Ni(OH)2 and then disintegrates and reduces to Ni, and Ni + NiSO4 stepwise catalysis includes two steps of pre-catalysis and secondary catalysis. After fourth cyclic experiment, the vanadium content of V2O3 product obtained was 67.46 % (i.e. 99.21 % V2O3 purity met the requirements of GB 40301–2021), the total recovery was 98.68 %, and the vanadium loss ratio was stable at 1.22 %. The process of SpHR has no ammonia nitrogen wastewater or waste gas discharge, and the price of V2O3 with purity more than 99 % on the market is about 260,000 ¥/t. The stepwise catalysis SpHR has remarkable environmental benefits and economic benefits.

Visualization of the structural transformation of NiO/YSZ/BZY nanocomposite particles using in situ gas environmental transmission electron microscopy.

This study focused on investigating the dynamic structural transformations of spherical NiO/YSZ/BZY triple-phase nanocomposite particles, commonly employed for cermet anodes, during the hydrogen reduction reaction. We utilized both spherical aberration (Cs) corrected transmission electron microscopy (TEM) and high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) observation modes under a controlled gaseous environment. The environmental gas pressure was set to 1 atm (760 Torr), mirroring real-world conditions. To elucidate pre- and post-hydrogen reduction compositional alterations, we conducted elemental mapping using energy-dispersive X-ray spectroscopy (EDS). Our findings indicated that NiO nanoparticles underwent reduction to Ni particles upon heat treatments in an environment containing H2 gas. Significantly, this reduction of NiO led to the migration of Ni along the external surface of each composite particle, ultimately resulting in the agglomeration at the interparticle spaces among the three NiO/YSZ/BZY nanocomposite particles.

Highly bifunctional Rh2P on N,P-codoped carbon for hydrazine oxidation assisted energy-saving hydrogen production.

Highly pure Rh2P nanoparticles on N,P-codoped carbon were synthesized by a simple "mix-and-pyrolyze" method using one kind of low-cost nucleotide as the carbon, nitrogen and phosphorus source, which exhibits excellent bifunctional activity for the hydrogen reduction and hydrazine oxidation reactions, achieving energy-efficient hydrogen production.

Hydrogen Reduction Reduction (HRR)

The year 2023 marks the bicentennial of the discovery of heterogeneous H2 catalysis. Nowadays, the hydrogen oxidation reaction (HOR), which converts H2 to protons (H+), is one of the most important transformations in energy research. Meanwhile, hydrogenation reactions, which transfer net H-atoms (H·) to organic substrates from H2, play pivotal roles in various chemical industries. In comparison, it is surprising to see that a heterogenous catalytic reaction that directly converts H2 to hydrides (H–) still remains elusive. Hydride transfer is a critical elementary reaction step that spans biological catalysis, organic synthesis and energy conversion. Conventionally, hydride transfer reactions are performed using (bio)molecular hydride reagents under homogeneous conditions. Here we report a conceptually distinct heterogeneous hydride transfer reaction via the net electrocatalytic hydrogen reduction reaction (HRR), which reduces H2 to hydrides. The reaction proceeds by H2 dissociative adsorption on a metal electrode to form surface M−H species, which are then negatively polarized to drive hydride transfer to molecular hydride acceptors with up to 91% Faradaic efficiency. The hydride transfer reactivity of surface M−H species is highly tunable, and, depending on the electrode potential, the thermodynamic hydricity of Pt−H on the same Pt electrode can continuously span a range of >40 kcal/mol.In addition to this electrochemical transformation, we further developed an alternative strategy to achieve heterogeneous hydride transfer on dispersed metal catalysts under non-electrochemical conditions. In the presence of a base, deprotonation of surface M-H builds up electron density at the metal surface and thereby causes spontaneous polarization which can then drive hydride transfer from metal nanoparticles. Based on this, HRR can be performed under standard hydrogenation conditions with the addition of a base using dispersed metal catalysts, and the surface hydricity is now controlled by the solution basicity. We further demonstrate that this non-electrochemical HRR method can be applied to NADH regeneration which is closely related to industrial biocatalysis. The discovery of HRR reveals the fundamental hydride transfer reactivity of surface M-H species as well as its polarization-dependent nature. Both the electrochemical and non-electrochemical HRR methods establish sustainable strategies for accessing reactive hydrides directly from H2. Figure 1

Boosting Photocatalytic Water Splitting of Polymeric C60 by Reduced Dimensionality from Two-Dimensional Monolayer to One-Dimensional Chain.

The recent synthesis of monolayer fullerene networks (Hou, L., et al. Nature 2022, 606, 507) provides new opportunities for photovoltaics and photocatalysis because of their versatile crystal structures for further tailoring of electronic, optical, and chemical function. To shed light on the structural aspects of the photocatalytic water splitting performance of fullerene nanomaterials, we compare the photocatalytic properties of individual polymeric fullerene chains and monolayer fullerene networks from first-principles calculations. We find that the photocatalytic efficiency can be further optimized by reducing the dimensionality from two-dimensional (2D) to one-dimensional (1D). The conduction band edge of the polymeric C60 chain provides an external potential for the hydrogen reduction reaction much higher than that of its monolayer counterparts over a wider range of pH values, and there are 2 times more surface active sites in the 1D chain than in the 2D networks from a thermodynamic perspective. These observations identify the 1D fullerene polymer as a more promising candidate as a photocatalyst for the hydrogen evolution reaction in comparison to monolayer fullerene networks.

Inorganic Oxide-Based "Hydrophobic-Hydrophilic-Hydrophobic" Separators Systems for Long-Life Zinc-Ion Batteries.

Hydrogen reduction reaction (HER) and corrosion limit the long-life cycle of zinc-ion batteries. However, hydrophilic separators are unable to prevent direct contact between water and electrodes, and hydrophobic separators have difficulty in transporting electrolytes. In this work, an inorganic oxide-based "hydrophobic-hydrophilic-hydrophobic" self-assembled separator system is proposed. The hydrophobic layer consists of a porous structure, which can isolate a large amount of free water to avoid HER and corrosion reactions, and can transport electrolyte by binding water. The middle hydrophilic layer acts as a storage layer consisting of the GF separator, storing large amounts of electrolyte for proper circulation. By using this structure separator, Zn||Zn symmetric cell achieve 2200h stable cycle life at 5mA cm-2 and 1mAh cm-2 and still shows a long life of 1800h at 10mA cm-2 and 1mAh cm-2. The assembled Zn||VO2 full cell displays high specific capacity and excellent long-term durability of 60.4% capacity retention after 1000 cycles at 2C. The assembled Zn||VO2 pouch full cell displays high specific capacity of 172.5mAh g-1 after 40 cycles at 0.5C. Changing the inorganic oxide materials, the hydrophobic-hydrophilic-hydrophobic structure of the separators still has excellent performance. This work provides a new idea for the engineering of water-based battery separators.

Transition-metal sulfides with excellent hydrogen and oxygen reactions: A mini-review

In order to create sustainable, environmentally friendly energy systems, the Hydrogen Evolution Reaction and Oxygen Evolution Reaction must be prioritized. Transition metal sulfides (TMSs) have been studied extensively as catalysts for both HER and OER because of their high activity, cheap cost, and availability. However, its low stability and conductivity limit its usefulness. Recent research efforts have focused on developing TMS-based nanocomposites, which combine the advantageous properties of TMSs with those of other materials, in order to overcome these concerns. The latest advances in TMS-based nanocomposites for oxygen reduction reaction and hydrogen reduction reaction are outlined in this article. We begin by discussing the broad concepts of HER and OER and the problems of TMSs in these reactions. We have comprehensively addressed the role of Sulfur atoms in electrocatalytic water splitting. We also emphasize the need to improve the contact between TMSs and other materials to enable effective charge transfer. Lastly, we evaluate the performance of TMS-based nanocomposites in HER and OER and compare their activity to that of other cutting-edge catalysts. We also examine the remaining research problems and potential in this subject. TMS-based nanocomposites show significant potential for practical applications of HER and OER in renewable energy systems.

Variable metal valence states with band-edge shift over in-situ annealed CuTi-LDH nanosheets for efficient hydrogen and oxygen reduction reactions

Variable metal valence states with band-edge shift over in-situ annealed CuTi-LDH nanosheets for efficient hydrogen and oxygen reduction reactions