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Development and utilization of hydrogen energy is an effective way to achieve carbon neutrality, only hydrogen production through electrolytic water splitting meets the goal of zero carbon emission. To facilitate the large‐scale commercialization of water splitting devices, the development of highly efficient and low‐cost catalysts to reduce the energy consumption is essential. MoS2 has been regarded as a promising electrocatalyst to replace platinum in hydrogen evolution reaction due to its low price and unique 2D layered structure. However, the poor conductivity and inert basal planes of MoS2 limited its wide‐spread application. Recently, researches have demonstrated that the conductivity and active sites of MoS2 can be improved by heteroatoms doping or constructing of heterogeneous structures. In this review, the recent progress of Mo‐based catalysts are summarized centered on MoS2 based on interface engineering and anion engineering, including MoS2–MoO2, MoS2–Mo2C, MoS2–MoNx, MoS2–MoP, and MoS2–MoSe2. The preparation method, structure, and performance of the catalysts are introduced and the possible mechanism behind the improved catalytic activity are revealed to give readers an overall comprehension on the progress of the Mo‐based electrocatalysts for hydrogen evolution reaction. In addition, an outlook on future opportunities and development directions of Mo‐based catalysts are proposed to facilitate the development of Mo‐based catalysts for hydrogen production. [ABSTRACT FROM AUTHOR]

Developing high‐efficiency bifunctional electrocatalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) to realize low‐cost water splitting is the premise for large‐scale production of hydrogen. The catalytic activity of an electrocatalysts greatly depends on its composition and structure. In this work, we report the preparation of hollow CoS2/MoS2 heterostructure using ZIF‐67 as the precursor. The ratio of Co and Mo are optimized to maximize the synergy of CoS2 and MoS2, due to their specific catalytic activity for OER and HER. The optimized CoS2/MoS2 exhibits good bifunctional catalytic activity in view of its low overpotentials for HER (170 mV) and OER (270 mV), as well as small cell voltage of 1.66 V for overall water splitting. This work provides a facile strategy to controllable fabrication of efficient bifunctional electrocatalysts for renewable energy applications. [ABSTRACT FROM AUTHOR]

Single‐atom catalysts (SACs) have attracted increasing research interests owing to their unique electronic structures, quantum size effects and maximum utilization rate of atoms. Metal organic frameworks (MOFs) are good candidates to prepare SACs owing to the atomically dispersed metal nodes in MOFs and abundant N and C species to stabilize the single atoms. In addition, the distance of adjacent metal atoms can be turned by adjusting the size of ligands and adding volatile metal centers to promote the formation of isolated metal atoms. Moreover, the diverse metal centers in MOFs can promote the preparation of dual‐atom catalysts (DACs) to improve the metal loading and optimize the electronic structures of the catalysts. The applications of MOFs derived SACs and DACs for electrocatalysis, including oxygen reduction reaction, oxygen evolution reaction, hydrogen evolution reaction, carbon dioxide reduction reaction and nitrogen reduction reaction are systematically summarized in this Review. The corresponding synthesis strategies, atomic structures and electrocatalytic performances of the catalysts are discussed to provide a deep understanding of MOFs‐based atomic electrocatalysts. The catalytic mechanisms of the catalysts are presented, and the crucial challenges and perspectives are proposed to promote further design and applications of atomic electrocatalysts. [ABSTRACT FROM AUTHOR]

Oxygen reduction reaction (ORR) catalysts with hierarchical pore structures, high specific surface area and multiple heteroatoms doping is very attractive due to the rapid mass transport and abundant active sites. In this work, we reported a facile confined strategy to prepare N, P co‐doped hierarchical porous carbon (NPHC) and investigated their catalytic performance for ORR. The strategy greatly simplifies the synthesis procedure of 3D hierarchical carbon templated by SiO2, which can utilize small organic molecules as carbon sources and avoids the pre‐polymerization and post‐washing process. Moreover, this strategy can be readily extended to synthesis other carbons by simply changing the carbon sources and heteroatom sources, or to synthesize metal compounds/carbon composites by adding metal sources during the synthesis process for energy conversion and storage. [ABSTRACT FROM AUTHOR]

Advances in colloidal chemistry allow to prepare well‐controlled nanostructures, while application of the colloids in heterogeneous catalysis is strongly impeded by the presence of organic capping layers. However, removal of the protection layers inevitably results in changes of the well‐defined nanostructures such as sintering and agglomeration. Here, a simple way is suggested to solve the dilemma by replacing the organic capping layers with another flexible but robust capping layers made of two‐dimensional materials. We show simultaneous removal of surfactant layers in B‐containing Ni, Co, and Fe colloids and formation of hexagonal boron nitride (h‐BN) capping layers over metal nanoparticles. Metal particle size can be well kept even upon thermal treatment at 850 °C and Ni nanocatalysts embedded within h‐BN shells present high catalytic performance in water‐gas shift reaction. This work suggests a facile strategy to promote the application of metal colloids in heterogeneous catalysis. [ABSTRACT FROM AUTHOR]

It is of increasing importance to develop highly active and economical oxygen reduction reaction (ORR) electrocatalysts, which have great significance for the large‐scale implementation of various energy conversion systems, including metal–air batteries and fuel cells. Herein, a novel method to synthesize FeNx‐decorated carbon nanotubes as a high‐efficiency ORR catalyst, by utilizing ZnO nanowires as a sacrificial template and a Fe–polydopamine complex as metal and carbon sources, is reported. The obtained catalyst shows great potential for replacing Pt/C as the ORR catalyst under various pH conditions, from alkaline to acidic electrolytes. The high conductivity, large surface area of the carbon nanotube, and highly active FeNx species contributed greatly to the high performance of the catalyst. The work presented herein paves a new way for the synthesis of 1D porous nanomaterials for a broad range of energy‐related applications. Doped to reduce: FeNx‐decorated carbon nanotubes are prepared by utilizing ZnO nanowires as a sacrificial template and Fe–polydopamine (Fe–PDA) complex as metal and carbon sources (see figure). The evaporation of Zn at high temperature results in a high surface area of the carbon nanotubes, and the FeNx species contribute greatly to the oxygen reduction reaction activity of the catalyst. [ABSTRACT FROM AUTHOR]