Catalysts For Hydrogen Evolution Research Articles

Retraction Note: Co5.47 N/rGO@NF as a High-Performance Bifunctional Catalyst for Urea-Assisted Hydrogen Evolution

Retraction Note: Co5.47 N/rGO@NF as a High-Performance Bifunctional Catalyst for Urea-Assisted Hydrogen Evolution

Atmosphere-driven metal-support synergy in ZnO/Au catalysts for efficient piezo-catalytic hydrogen evolution

Piezo-catalysis, which leverages mechanical energy to drive chemical reactions, is emerging as a promising method for sustainable energy production. While the enhancement of piezo-catalytic performance through metal-support interactions is well-documented, the critical influence of the synthesis atmosphere during metal-loaded piezo-catalyst preparation has been a notable gap in the field. To this end, we systematically investigate how different atmospheric conditions during the synthesis of catalysts—without gas flow or with Ar, N2 and O2—affect metal dispersion, oxidation states, piezo-carrier dynamics, and electronic structure, and subsequently shape the metal-support interactions and piezo-catalytic activity. ZnO/Au, with Au deposited on ZnO, is selected as the model system, and hydrogen evolution reaction is used as the probe reaction. Our results demonstrate that an oxygen-enriched atmosphere significantly enhances the metal-support interactions, achieving an ultrahigh net hydrogen yield of 16.5 mmol·g–1·h–1 on ZnO/Au, a 3.58-fold increase over pristine ZnO. Specifically, the performance improvements substantially surpass those synthesized under other atmospheric conditions. Conversely, exposure to CO2 transforms the ZnO support into ZnCO3, adversely affecting its catalytic activity. These findings reveal the crucial impact of synthesis conditions on piezo-catalyst performance and thereby open new avenues for optimizing catalyst systems for enhanced sustainability.

Tobacco stem-derived porous carbon-supported Ru catalysts for efficient electrochemical hydrogen evolution

Tobacco stem-derived porous carbon-supported Ru catalysts for efficient electrochemical hydrogen evolution

In-situ synthesis nano PtRuW/WC HER catalyst for acid hydrogen evolution by microwave method

Abstract One of the primary challenges in electrocatalysis for the hydrogen evolution reaction (HER) lies in the development of highly efficient catalysts suitable in acidic environments. Tungsten carbide-based materials have long been proposed as potential substitutes for Pt due to their “Pt-like” electronic properties in the HER process. However, tungsten carbide still falls short of the performance exhibited by commercial precious-metal catalysts. Herein, PtRuW/WC was prepared by a microwave heating method and acted as a HER electrocatalyst. The microwave method not only enhances the diffraction peaks of the substrate tungsten carbide, but also facilitates the growth of metal ions at specific sites. The PtRuW/WC catalyst demonstrates outstanding performance in acidic HER, characterized by a minimal overpotential of 40.7 mV at 10 mA/cm2 (η10). Furthermore, it exhibits exceptional stability in acidic solutions, showing no substantial degradation during 20 h at 1000 mA/cm2. The catalyst-assembled PEM electrolytic water electrode further proves that PtRuW/WC has excellent electrolytic water performance and makes some efforts for the development of commercial PEM electrolytic water.

In Situ Growth of MoN on Nickel Foam for Highly Efficient Hydrogen Evolution in Alkaline Solution.

Highly efficient, stable, and low-cost hydrogen evolution catalysts are urgently required for water electrolysis. Herein, a method for in situ growth of medium-nitrogen nanosheet MoN catalysts with a large electrochemical surface area on nickel foam (NF) is proposed. The results show that the morphology of the as-prepared catalysts greatly depends on the nitrogen sources and nitridation temperature. The MoN/NF catalyst nitride at 700 °C using melamine as a nitrogen source exhibits a spindle-like morphology consisting of stacked nanosheets, which is conducive to exposing more active sites, thereby increasing the catalyst activity. The N atoms in MoN could adjust the chemical environment of the metal by changing the density of the d-band electron state, which further improves the HER performance. Benefiting from the regulation of Mo charge distribution and exposure to more active sites through N doping and morphological control, the MoN/NF catalyst exhibits superior HER performance with an overpotential of 70 mV at a current density of 10 mA·cm-2, a Tafel slope of 44.3 mV dec-1, and an Rct of 1.83 Ω, indicating high HER catalytic activity, fast kinetics, and excellent conductivity. Theoretical calculations reveal that among the (002), (202), and (200) planes of MoN, the (202) plane exhibits the lowest value of |ΔGH*| (0.47 eV), which is close to that of Pt(111) (0.14 eV). More importantly, MoN(202) also has the smallest work function of 3.58 eV, indicating an enhanced capability to offer electrons. This work develops a strategy to design high-performance and low-cost transition-metal nitride HER catalysts.

Metal Cocatalyst Engineering in Metal-Semiconductor Hybrid Photocatalysts Achieves a Fivefold Enhancement of Hydrogen Evolution.

This study explores the optimal morphology of photochemical hydrogen evolution catalysts in a one-dimensional system. Systematic engineering of metal tips on precisely defined CdSe@CdS dot-in-rods is conducted to exert control over morphology, composition, and both factors. The outcome yields an optimized configuration, a Au-Pt core-shell structure with a rough Pt surface (Au@r-Pt), which exhibits a remarkable fivefold increase in quantum efficiency, reaching 86 % at 455 nm and superior hydrogen evolution rates under visible and AM1.5 G irradiation conditions with prolonged stability. Kinetic investigations using photoelectrochemical and time-resolved measurements demonstrate a greater extent and extended lifetime of the charge-separated state on the tips as well as rapid water reduction kinetics on high-energy surfaces. This approach sheds light on the critical role of cocatalysts in hybrid photocatalytic systems for achieving high performance.

FePt bimetallic nanoparticles: A highly efficient hydrogen evolution catalyst with tunable d-band center

FePt bimetallic nanoparticles: A highly efficient hydrogen evolution catalyst with tunable d-band center

Electrodeposited zinc cobalt bimetallic phosphate as a bifunctional catalyst for hydrogen evolution and urea oxidation

The theoretical potential of the urea oxidation reaction (UOR) is a mere 0.37 V(vs.RHE), significantly lower than the 1.23 V (vs. RHE) of the oxygen evolution reaction (OER). Thus, substituting the OER with the UOR can effectively reduce the voltage required for electrolysis. Transition metal phosphates (TM-Pi), with their unique physical properties, can partly replace precious metal catalysts and hold great application potential. However, further modification is necessary to enhance their catalytic activity and stability. Therefore, this study prepared a coral-like cluster Co/Zn-Pi@NF (Pi represents phosphate) catalyst, which was grown in situ on nickel foam (NF) using the constant current electrodeposition method. The catalyst exhibited superior catalytic performance in 1 M KOH, with the required overpotentials for the hydrogen evolution reaction (HER) and OER reaching 10 mA·cm−2 being 36.6 mV and 343.4 mV, respectively. In 1 M KOH containing 0.5 M urea, the urea oxidation potential was only 1.4 V, which remained stable for 60 hours. The Co/Zn-Pi@NF nanoparticles were used as the anode and cathode for water-urea electrolysis, and the electrolysis voltage was 1.43 V at a current density of 10 mA·cm−2, which was 290 mV lower than that of electrolyzed water. This study demonstrates that zinc-cobalt bimetallic phosphate can be used as a dual-function electrocatalyst for hydrogen evolution and urea oxidation.

Cauliflower-like Pd/MoC||Mo2C/C heterostructure as an efficient trifunctional catalyst for formic acid oxidation, hydrogen evolution, and oxygen reduction reactions

The use of Pd-based catalytic materials as electrocatalysts for formic acid oxidation reaction (FAO), hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR) has been well-established for some time. The incorporation of a second phase can markedly enhance the electronic properties of the composites. The combination of different compounds with superior electronic properties is crucial for the design and preparation of catalysts with optimal catalytic activity and stability. In this study, a novel cauliflower-like Pd/MoC||Mo2C/C composite with heterostructure is synthesised, which exhibits excellent catalytic activity and long-term stability against FAO, HER, and ORR. The high-temperature treatment results in the formation of small-sized Mo₂C and MoC nanoparticles on the carbonaceous substrate, thereby exposing a greater number of Mo and Mo-C active sites. The formation of heterostructures between Mo₂C and MoC optimises the electronic structure of the composite, thereby facilitating enhanced reaction processes. In terms of FAO, the mass activity of Pd/MoC||Mo2C/C is 1.87A mgPd-1, which is 2.75 times higher than that of Pd/C (0.68A mgPd-1). As for the HER, a much lower overpotential of 28mV is required to achieve a current density of 10mAcm-2 compared to Pd/C (40mV). Fortunately, Pd/MoC||Mo2C/C also shows excellent ORR activity with a half-wave potential of 0.798V and the maximum current density of approximately 5.73mAcm-2 in alkaline electrolyte. These findings may contribute to the development of other noble metal-based materials loaded on intermetallic compounds with stable and effective electrocatalytic performance.

Advances in Shell and Core Engineering of Carbonized Polymer Dots for Enhanced Applications.

ConspectusCarbon dots (CDs), as a novel type of fluorescent nanocarbon material, attract widespread attention in nanomedicine, optoelectronic devices, and energy conversion/storage due to their excellent optical properties, low toxicity, and high stability. They can be classified as graphene quantum dots, carbon quantum dots, and carbonized polymer dots (CPDs). Among these, CPDs exhibit tunable structures and components that allow fine-tuning of their optoelectronic properties, making them one of the most popular types of CDs in recent years. However, the structural complexity of CPDs stimulates deep exploration of the relationship between their unique structure and luminescent performance. As an organic-inorganic hybrid system, the diversity of self-limited quantum state carbon cores and polymer-hybrid shell layers makes understanding the underlying mechanisms and structure-property relationships in CPDs a very challenging task. In this context, elucidating the structural composition of CPDs and the factors that affect their optical properties is vital if the enormous potential of CPDs is to be realized. Achieving controllable structures with predefined optical properties via the adoption of specific functionalization strategies is the prized goal of current researchers in the field.In this Account, we describe the efforts made by our group in the synthesis, mechanism analysis, structural regulation, and functional applications of CPDs, with particular emphasis on the design of CPDs core-shell structures with tailored optoelectronic properties for applications in the fields of optoelectronics and energy. Specifically, through the rational selection of precursors, optimization of reaction conditions, and postmodification strategies for CPDs, we have demonstrated that it is possible to regulate both the carbon core and polymer shell layers, thereby achieving full-spectrum emission, high quantum yield, persistent luminescence, thermally activated delayed fluorescence, and laser action in CPDs. Furthermore, we have established structure-performance relationship in CPDs and proposed a universal strategy for synergistic interactions between hybrid carbon-based cores and surface micronanostructures. In addition, we unveiled a novel luminescence mechanism in cross-linked CPDs, specifically "cross-linking synergistically inducing quantum-state luminescence", which addresses the challenge of efficient circularly polarized luminescence in the liquid and solid phases of CPDs. Subsequently, strong cross-linking, dual-rigidity, and ordering preparation methods were introduced, thereby pioneering tunable laser emission from blue to near-infrared wavelengths. Additionally, we developed a new strategy of "confined composite nanocrystals of CPDs", leading to various high-performance hydrogen evolution catalysts for water electrolysis. The CPDs developed by this strategy not only possessed excellent optical properties but also enabled high efficiencies in field of energy conversion, thus maximizing the utilization of CPDs. Finally, we discuss important new trends in CPD research and development. Overall, this Account summarizes the latest advancements in CPDs in recent years, providing case-studies that enable deep understanding of structure-property-performance relationships and regulation strategies in CPDs, guiding the future expansion and application of CPDs.

Synthesis and recent developments of MXene-based composites for photocatalytic hydrogen production

Abstract The energy crisis has already seriously affected the daily lives of people around the world. As a result, designing efficient catalysts for photocatalytic hydrogen evolution (PHE) is a promising strategy for energy supply. Co-catalyst modification can significantly enhance the photocatalytic activity of single semiconductors, overcoming limitations posed by their narrow visible light absorption range and high electron–hole recombination rate. MXene-based composites demonstrate immense potential as co-catalysts for photocatalytic hydrogen production owing to their distinctive two-dimensional layered structure and outstanding photoelectrochemical properties, and further research and development efforts surrounding MXene-based composites will contribute significantly to the progress of sustainable energy technologies. In this review, we offer a comprehensive overview of synthesis methods for MXene and MXene-based composites, highlight illustrative instances of binary and ternary MXene-based composites in PHE, and explore potential avenues for future research and expansion of MXene-based composites.

Alkali Metals Activated High Entropy Double Perovskites for Boosted Hydrogen Evolution Reaction.

An efficient and facile water dissociation process plays a crucial role in enhancing the activity of alkaline hydrogen evolution reaction (HER). Considering the intricate influence between interfacial water and intermediates in typical catalytic systems, meticulously engineered catalysts should be developed by modulating electron configurations and optimizing surface chemical bonds. Here, a high-entropy double perovskite (HEDP) electrocatalyst La2(Co1/6Ni1/6Mg1/6Zn1/6Na1/6Li1/6)RuO6, achieving a reduced overpotential of 40.7mV at 10mA cm-2 and maintaining exemplary stability over 82 h in a 1m KOH electrolyte is reported. Advanced spectral characterization and first-principles calculations elucidate the electron transfer from Ru to Co and Ni positions, facilitated by alkali metal-induced super-exchange interaction in high-entropy crystals. This significantly optimizes hydrogen adsorption energy and lowers the water decomposition barrier. Concurrently, the super-exchange interaction enhances orbital hybridization and narrows the bandgap, thus improving catalytic efficiency and adsorption capacity while mitigating hysteresis-driven proton transfer. The high-entropy framework also ensures structural stability and longevity in alkaline environments. The work provides further insights into the formation mechanisms of HEDP and offers guidelines for discovering advanced, efficient hydrogen evolution catalysts through super-exchange interaction.

3D hierarchical nanostructured NiCo-LDH/Cu electrode for efficient alkaline hydrogen evolution

The development of an efficient and cost-effective electrocatalyst for the Hydrogen Evolution Reaction (HER) that can be widely applied in industrial settings poses a multifaceted challenge. This research involved fabricating a NiCo-LDH/Cu electrode as a self-supported catalyst for hydrogen evolution on nickel foam using a solvothermal method and constant potential electrodeposition. In comparison to the NiCu electrocatalyst produced through a single-step electrodeposition, the NiCo-LDH/Cu hydrogen evolution electrode prepared via this combined approach exhibited significant electrocatalytic performance for HER in an alkaline electrolyte. The NiCo-LDH/Cu catalytic electrode requires only an overpotential of 78.0 mV to achieve a current density of 10 mA·cm−2 in 1 M KOH. The current density required to catalyze the hydrogenation reaction is reduced by 64 % compared to pure nickel foam. This reduction accelerates the hydrogenation catalytic reaction and enhances electrochemical stability. The remarkable HER efficiency of the NiCo-LDH/Cu catalytic electrode primarily stems from the increased active surface area facilitated by the LDH structure and the synergistic impact generated during the NiCu co-deposition process. This work shows an economical and practical method for developing efficient non-precious metal catalytic electrodes.

Orbital coupling of Pt single crystal via decoration of hetero-diatomic nickel-cobalt for efficient hydrogen evolution

Loading active metals in forms of single atoms or nanocluster is considered as an effective approach for designing catalysts with high atomic utilization efficiency. However, synthesis single atoms or clusters precisely in large quantities is a challenge. In this work, the isolated diatomic sites (Ni, Co) decorated single crystal Pt cluster were synthesized as efficient catalyst for hydrogen evolution. Adjacent Ni and Co atoms optimize the electronic structure of Pt single crystal, effectively lowering the water dissociation barrier and ensuring optimal binding strength of intermediates throughout the reaction process. As results, the mass activity of 2.087 A mg−1 was achieved under 200 mA cm−2, approximately 3 times than that of Pt/C. Theoretical calculations reveal that diatomic Ni, Co decorated Pt cluster reduces the energy barrier for breaking the OH-H bond, as well as facilitating the preferential adsorption and dissociation of H*. This work provides an opportunity for regulation electronic structure of catalytic via decoration single crystal cluster with diatomic sites and provides guidance for designing high efficiency electrocatalysts for promising applications.

Collaborative effect between single-atom Re and S vacancy on modulating localized electronic structure of MoS2 catalysts for alkaline hydrogen evolution

Collaborative effect between single-atom Re and S vacancy on modulating localized electronic structure of MoS2 catalysts for alkaline hydrogen evolution

Robust self-supporting MoS2@Ni2B-GO/CNT electrode for enhanced hydrogen evolution reaction in acidic medium

Molybdenum sulphide (2D-MoS2) promises great potential as a hydrogen evolution (HER) catalyst, especially, when combined with conductive carbon supports like graphene oxide (GO) and carbon nanotubes (CNT). However, the hydrophobic nature of these carbon supports limits the catalytic potential of MoS2. To overcome this, we introduced hydrophilic Nickel Boride (Ni2B) into GO/CNT electrodes (Ni2B-GO/CNT), enhancing wettability (Contact angle-25.3°) and HER activity. By hydrothermally depositing MoS2 onto the hydrophilic Ni2B-GO/CNT electrode, we fabricated a self-supporting MoS2@Ni2B-GO/CNT electrode. The MoS2 deposition led to the formation of MoS2@Ni2B-GO/CNT heterostructure with multiple interfaces, favoring interfacial electronic redistribution (XPS) to significantly improve the HER activity. Thus, the proposed MoS2@Ni2B-GO/CNT electrode exhibited an excellent durability of 100 h (97%) and an overpotential of 224 mV at 10 mA cm−2 in acidic medium.

Highly Sustainable h-BN Encapsulated MoS2 Hydrogen Evolution Catalysts.

Despite the importance of the stability of the 2D catalysts in harsh electrolyte solutions, most studies have focused on improving the catalytic performance of molybdenum disulfide (MoS2) catalysts rather than the sustainability of hydrogen evolution. In previous studies, the vulnerability of MoS2 crystals is reported that the moisture and oxygen molecules can cause the oxidation of MoS2 crystals, accelerating the degradation of crystal structure. Therefore, optimization of catalytic stability is crucial for approaching practical applications in 2D catalysts. Here, it is proposed that monolayered MoS2 catalysts passivated with an atomically thin hexagonal boron nitride (h-BN) layer can effectively sustain hydrogen evolution reaction (HER) and demonstrate the ultra-high current density (500mAcm⁻2 over 11 h) and super stable (64 h at 150mAcm⁻2) catalytic performance. It is further confirmed with density functional theory (DFT) calculations that the atomically thin h-BN layer effectively prevents direct adsorption of water/acid molecules while allowing the protons to be adsorbed/penetrated. The selective penetration of protons and prevention of crystal structure degradation lead to maintained catalytic activity and maximized catalytic stability in the h-BN covered MoS2 catalysts. These findings propose a promising opportunity for approaching the practical application of 2D MoS2 catalysts having long-term stability at high-current operation.

Effect of Catalyst and Electrode Structures on the Operating Current Densities of Liquid Alkaline Water Electrolyzers

Liquid Alkaline Water Electrolyzers (LAWEs) stand out as the technology best-suited for cost-effective hydrogen production. They do not require expensive platinum group metal catalysts and have proven durability afforded by nickel-based electrodes and porous separators. While nickel electrodes and porous separators provide chemical stability in highly alkaline conditions, they do suffer from lower catalytic activity for hydrogen and oxygen evolution reactions (HER and OER), and separators possess higher ohmic resistance due to the absence of ion-conducting groups. Consequently, most LAWEs operate at low current densities ranging from 0.2 to 0.6 A/cm2, resulting in a bulky footprint and comparatively lower energy efficiency due to a reduced hydrogen production rate. To address these challenges, considerable efforts have been directed towards developing thin separators and efficient transition metal-based electrocatalysts for HER and OER in alkaline media. However, the majority of studies related to catalysts are limited to half cells, with only a limited number of catalysts evaluated in relevant LAWE configurations.In this work, we introduce a next-generation Zero-gap LAWE testing capability, benchmarked for performance through H2NEW consortia. Employing this setup, we have evaluated hydrogen and oxygen evolution catalysts under LAWE-relevant conditions on different electrode substrates, each offering a unique electrode structure. Our preliminary findings indicate that Zero-gap LAWEs, when coupled with NiMo cathode and NiFe-type anode catalysts, can operate at current densities exceeding 0.75 A/cm2 at approximately 1.8 V without compromising their short-term durability. In contrast, the benchmark cell exhibited a meager current density of around 0.22 A/cm2. In this presentation, effects of electrode structure, catalyst type, and other relevant parameters related to Zero-gap LAWEs will be discussed in detail. Acknowledgement:This research is supported by the U.S. Department of Energy (DOE) Hydrogen and Fuel Cell Technologies Office through the Hydrogen from Next-generation Electrolyzers of Water (H2NEW) consortium.

Direct Anchoring of Molybdenum Sulfide Molecular Catalysts on Antimony Selenide Photocathodes for Solar Hydrogen Production.

Molybdenum sulfide serves as an effective nonprecious metal catalyst for hydrogen evolution, primarily active at edge sites with unsaturated molybdenum sites or terminal disulfides. To improve the activity at a low loading density, two molybdenum sulfide clusters, [Mo3S4]4+ and [Mo3S13]2-, were investigated. The Mo3S x molecular catalysts were heterogenized on Sb2Se3 with a simple soaking treatment, resulting in a thin catalyst layer of only a few nanometers that gave up to 20 mA cm-2 under one sun illumination. Both [Mo3S4]4+ and [Mo3S13]2- exhibit catalytic activities on Sb2Se3, with [Mo3S13]2- emerging as the superior catalyst, demonstrating enhanced photovoltage and an average faradaic efficiency of 100% for hydrogen evolution. This superiority is attributed to the effective loading and higher catalytic activity of [Mo3S13]2- on the Sb2Se3 surface, validated by X-ray photoelectron and Raman spectroscopy.

Earth-Abundant Metal Oxides as Oxygen Evolution Electrocatalysts in 1 M H2SO4

Water splitting is a very hot research topic as a preferred source for green hydrogen, as a key vector to facilitate a transition into an environmentally friendly and sustainable energy economy in the mid-term. But it is still far from being economically competitive with respect to current hydrogen production technologies based on fossil fuels. One of the major economic hurdles to reduce electrolysis costs is the lack of low-cost catalysts for hydrogen evolution and, more importantly, for oxygen evolution. The water oxidation process is considered the main bottleneck in the advancement of water splitting devices, since it is the rate limiting process, and the main cause of poor long-term performance.Most recent advances in the field of water oxidation catalysis are based on transition metal oxides, operating exclusively in alkaline electrolysis conditions. Unfortunately, these excellent oxygen evolution catalysts in basic pH ( > 13) rapidly lose their activity when the pH is lowered, and are far away from the performance exhibited by noble metals in acid solution. McCrory et al. established in 2013 1a benchmarking protocol to identify the potential of new OER electrocatalysts (and extended in 2015 2 to HER) comparing the initial activity and stability of the materials as a function of pH and showed how no other known catalysts at that time came close to the performance of IrOx-based materials.A simple processing technique using a partially hydrophobic binder has been proved to stabilize Co oxide, resulting in electrodes able to reach high current densities (> 10 mA cm-2) at competitive overpotentials and with long term stability for acidic OER catalysis3. Following this strategy, we have been able to conduct an extensive survey of the activity and stability of monometallic, binary and ternary earth-abundant transition metal oxides during electrocatalytic OER in 1 M H2SO4. Our results confirm the general validity of the strategy in using a partially hydrophobic electrode to confer high stability to common metal oxides under these harsh conditions.[1] C.C.L. McCrory, S. Jung, J.C. Peters, T.F. Jaramillo, Benchmarking heterogeneous electrocatalysts for the oxygen evolution reaction, J. Am. Chem. Soc. 135 (2013) 16977–16987.[2] C.C.L. McCrory, S. Jung, I.M. Ferrer, S.M. Chatman, J.C. Peters, T.F. Jaramillo, Benchmarking Hydrogen Evolving Reaction and Oxygen Evolving Reaction Electrocatalysts for Solar Water Splitting Devices, J. Am. Chem. Soc. 137 (2015) 4347–4357.[3] J. Yu, F.A. Garcés-Pineda, J. González-Cobos, M. Peña-Díaz, C. Rogero, S. Giménez, M.C. Spadaro, J. Arbiol, S. Barja, J.R. Galán-Mascarós, Sustainable oxygen evolution electrocatalysis in aqueous 1 M H2SO4 with earth abundant nanostructured Co3O4, Nat. Commun. 13 (2022) 4341. Figure 1