The discovery and identification of novel active sites are paramount for deepening the understanding of the catalytic mechanism and driving the development of remarkable electrocatalysts. Here, we reveal that the genuine active sites for the hydrogen evolution reaction (HER) in LaRuSi are Si sites, not the usually assumed Ru sites. Ru in LaRuSi has a peculiar negative valence state, which leads to strong hydrogen binding to Ru sites. Surprisingly, the Si sites have a Gibbs free energy of hydrogen adsorption that is near zero (0.063 eV). The moderate adsorption of hydrogen on Si sites during the HER process is also validated by in situ Raman analysis. Based on it, LaRuSi exhibits an overpotential of 72 mV at 10 mA cm-2 in alkaline media, which is close to the benchmark of Pt/C. This work sheds light on the recognition of real active sites and the exploration of innovative silicide HER electrocatalysts.

Highly Active Si Sites Enabled by Negative Valent Ru for Electrocatalytic Hydrogen Evolution in LaRuSi.

High activity and stability in Ni2P/(Co,Ni)OOH heterointerface with a multiple-hierarchy structure for alkaline hydrogen evolution reaction

Developing high‐efficiency electrocatalysts for the hydrogen evolution and oxidation reactions (HER/HOR) in alkaline electrolytes is of critical importance for realizing renewable hydrogen technologies. Ruthenium phosphides (RuPx) are promising candidates to substitute Pt‐based electrodes; however, great challenges still remain in their electronic structure regulation for optimizing intermediate adsorption. Herein, it is reported that a homologous RuP@RuP2 core–shell architecture constructed by a phosphatization‐controlled phase‐transformation strategy enables strong electron coupling for optimal intermediate adsorption by virtue of the emergent interfacial functionality. Density functional theory calculations show that the RuP core and RuP2 shell present efficient electron transfer, leading to a close to thermoneutral hydrogen adsorption Gibbs free energy of 0.04 eV. Impressively, the resulting material exhibits superior HER/HOR activities in alkaline media, which outperform the benchmark Pt/C and are among the best reported bifunctional hydrogen electrocatalysts. The present work not only provides an efficient and cost‐effective bifunctional hydrogen electrocatalyst, but also offers a new synthetic protocol to rationally synthesize homologous core–shell nanostructures for widespread applications.

Unlocking Interfacial Electron Transfer of Ruthenium Phosphides by Homologous Core–Shell Design toward Efficient Hydrogen Evolution and Oxidation

The discovery and identification of novel active sites are paramount for deepening the understanding of the catalytic mechanism and driving the development of remarkable electrocatalysts. Here, we reveal that the genuine active sites for the hydrogen evolution reaction (HER) in LaRuSi are Si sites, not the usually assumed Ru sites. Ru in LaRuSi has a peculiar negative valence state, which leads to strong hydrogen binding to Ru sites. Surprisingly, the Si sites have a Gibbs free energy of hydrogen adsorption that is near zero (0.063 eV). The moderate adsorption of hydrogen on Si sites during the HER process is also validated by in situ Raman analysis. Based on it, LaRuSi exhibits an overpotential of 72 mV at 10 mA cm−2 in alkaline media, which is close to the benchmark of Pt/C. This work sheds light on the recognition of real active sites and the exploration of innovative silicide HER electrocatalysts. 

Highly Active Si Sites Enabled by Negative Valent Ru for Electrocatalytic Hydrogen Evolution in LaRuSi

Herein, we developed a novel and simple strategy to construct Pt-decorated TiO 2 /β-Ni(OH) 2 nanosheet arrays that steadily deliver large current densities in alkaline electrolyte. It is of great interest to find that the versatile role of few-layered Ti 3 C 2 endows the unique growth mechanism of Pt/TiO 2 /β-Ni(OH) 2 . It is worth noting that the interconnected array electrode exhibits noticeable hydrogen evolution reaction (HER) performance, achieving ultralow overpotentials of 107, 145 and 184 mV at high current densities of 500, 1000 and 1500 mA cm −2 , respectively, which outperforms most reported HER electrocatalysts. It requires only 1.95 V to drive 1000 mA cm −2 towards full water electrolysis along with considerable stability. It is demonstrated for the first time that the synergistic effect of Pt and TiO 2 /Ni(OH) 2 the enhanced HER performance. This work reports a robust nanoarray support for Pt electrocatalyst to break through its intrinsic barrier in alkaline HER and under large current density. A novel and simple strategy was proposed to construct robust Pt-decorated TiO 2 /β-Ni(OH) 2 nanosheet arrays that steadily deliver industrial current densities at ultralow overpotentials in alkaline electrolyte. The unexpected HER activity originates from the synergy between Pt and TiO 2 /Ni(OH) 2 along with the interconnected array architecture. • Pt/TiO 2 /Ni(OH) 2 /NF possesses ultralow HER overpotential at high current density. • Pt/TiO 2 /Ni(OH) 2 /NF couple requires small cell voltage for overall water splitting. • 2D MXene endows the unique growth mechanism of Pt/TiO 2 /β-Ni(OH) 2 nanosheet. • The synergy between Pt and TiO 2 /Ni(OH) 2 contributes to the enhanced HER activity. • The interconnected array architecture overcomes the mass transfer resistance. 

Robust Pt/TiO2/Ni(OH)2 Nanosheet Arrays Enable Outstanding Performance for High Current Density Alkaline Water Electrolysis

Alloying is a well‐accepted strategy for modulating the electronic structures of catalyst materials. Compared to disordered solid‐solution alloys, intermetallic compounds feature ordered atomic arrangements and provide a unique platform with a rich and diverse resource to study the relationships among chemical composition, atomic structure, electronic structure, and properties. Unfortunately, it is still challenging to synthesize the nanostructures of intermetallic compounds for catalysis research. In this study, a series of intermetallic silicides (PtSi, RhSi, Ru2Si3, IrSi), germanide (Ru2Ge3), and stannides (Ru3Sn7, IrSn2, PdSn3, PdSn2) are rationally designed and constructed through a facile molten‐salt‐assisted route. As an example, the PtSi not only shows highly desirable electrocatalytic properties for the hydrogen evolution reaction (HER) with low overpotentials of 22, 38, and 66 mV at a current density of 10 mA cm‐2 in acidic, alkaline, and neutral media, respectively, but exhibits superior durability, as well as >97% faradic efficiency. The theoretical calculations suggest that the introduction of Si to Pt could weaken the binding energy between Pt and H atoms, which further facilitates the hydrogen generation during the HER process. Further, the findings inspired the authors to develop other kinds of metal‐based carbon‐group intermetallic phases with excellent activity in the HER and beyond.

General Synthesis of Transition‐Metal‐Based Carbon‐Group Intermetallic Catalysts for Efficient Electrocatalytic Hydrogen Evolution in Wide pH Range

Incorporating transition metal (TM) complexes into cluster-based chalcogenide frameworks is an effective synthetic strategy to induce structural diversity and to control the optoelectronic properties, which may further improve their photocatalytic...

Stable 3D neutral gallium thioantimonate frameworks decorated with transition metal complexes for tunable photocatalytic hydrogen evolution

Polynuclear silver clusters have attracted intensive attention in the academic community owing to their rich physicochemical properties. The development of thione-protected silver clusters has been lagging behind the well-explored thiolate-protected silver-sulfide clusters. Herein, we report two N-heterocyclic thione-protected silver clusters: [Ag4(2-TBI)6(SO4)3]2- (Ag4) and [Br@Ag8(2-TBI)12(SO4)2]3+ (Ag8) (2-TBI = 2-thiobenzimidazol), which cocrystallize to form cluster-based molecular crystals with a CaF2-type structure. The cocrystal shows high thermal stability in air. Notably, the two cluster-based layers are alternately assembled to exhibit a unique k-vector-differential crystallographic arrangement. This work may lay a foundation for synthesis of atomically precise and stable silver clusters using readily available N-heterocyclic thione ligands.

N-Heterocyclic Thione-Protected Ag4 Tetrahedra and Ag8 Cubes Cocrystallized in a Single Crystal.

Biomass is considered as a promising source to fabricate functional carbon materials for its sustainability, low cost, and high carbon content. Biomass‐derived‐carbon materials (BCMs) have been a thriving research field. Novel structures, diverse synthesis methods, and versatile applications of BCMs have been reported. However, there has been no recent review of the numerous studies of different aspects of BCMs‐related research. Therefore, this paper presents a comprehensive review that summarizes the progress of BCMs related research. Herein, typical types of biomass used to prepare BCMs are introduced. Variable structures of BCMs are summarized as the performance and properties of BCMs are closely related to their structures. Representative synthesis strategies, including both their merits and drawbacks are reviewed comprehensively. Moreover, the influence of synthetic conditions on the structure of as‐prepared carbon products is discussed, providing important information for the rational design of the fabrication process of BCMs. Recent progress in versatile applications of BCMs based on their morphologies and physicochemical properties is reported. Finally, the remaining challenges of BCMs, are highlighted. Overall, this review provides a valuable overview of current knowledge and recent progress of BCMs, and it outlines directions for future research development of BCMs.

https://onlinelibrary.wiley.com/doi/pdfdirect/10.1002/advs.202205557

Functional Carbon from Nature: Biomass‐Derived Carbon Materials and the Recent Progress of Their Applications

The types and quantities of surface ligands used in the synthesis of nanomaterials play a dominant role in determining their physical and chemical properties, and this situation likewise occurs in metal-chalcogenide supertetrahedral clusters (MCSCs). The MCSCs are mainly categorized into ligand-fully-protected MCSCs and ligand-free ones according to the surface ligand situation. However, ligand-partially-protected MCSCs are rarely reported. In this study, a facile synthetic strategy was proposed to create ligand-partially-protected MCSCs through the pyrolysis of the S-S or Se-Se bond of disulfide organic ligands in a solvothermal procedure, and a series of Pn-type MCSCs with their surface partially protected by thiophenol ligands (ISC-24-MnSnS: 10(3,5-DMPH+)·[Mn4Sn4S17]10-·4H2O; ISC-25-MnSnS-SPh: 7(3,5-DMPH+)·Mn4Sn4S14(SPh)37-·H2O; ISC-26-MnSnSeCl-SePh: 5.2(3,5-DMPH+)·Mn4Sn4Se12.2Cl0.8(SePh)45.2-·0.8(3,5-DMP)·4H2O; ISC-26-MnSnSeS-SPh: 6(3,5-DMPH+)·Mn4Sn4Se12S(SPh)46-·(3,5-DMP)·4H2O) were obtained. This work could lay a foundation for the synthesis of ligand-partially-protected MCSCs and other partially-protected nanomaterials through the cleavage of disulfide bonds in organic ligands.

Ning Chen

Papers

General Synthesis of Transition‐Metal‐Based Carbon‐Group Intermetallic Catalysts for Efficient Electrocatalytic Hydrogen Evolution in Wide pH Range

Stable 3D neutral gallium thioantimonate frameworks decorated with transition metal complexes for tunable photocatalytic hydrogen evolution

N-Heterocyclic Thione-Protected Ag4 Tetrahedra and Ag8 Cubes Cocrystallized in a Single Crystal.

Functional Carbon from Nature: Biomass‐Derived Carbon Materials and the Recent Progress of Their Applications

Ligand-partially-protected metal-chalcogenide supertetrahedral clusters.