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Electrochemical water splitting offers a most promising pathway for "green hydrogen" generation. Even so, it remains a struggle to improve the electrocatalytic performance of non‐noble metal catalysts, especially bifunctional electrocatalysts. Herein, aiming to accelerate the hydrogen and oxygen evolution reactions, an oxygen‐bridged cobalt–chromium (Co‐O‐Cr) dual‐sites catalyst anchored on cobalt phosphide synthesized through MOF‐mediation are proposed. By utilizing the filling characteristics of 3d orbitals and modulated local electronic structure of the catalytic active site, the well‐designed catalyst requires only an external voltage of 1.53 V to deliver the current density of 20 mA cm−2 during the process of water splitting apart from the superb HER and OER activity with a low overpotential of 87 and 203 mV at a current density of 10 mA cm−2, respectively. Moreover, density functional theory (DFT) calculations are utilized to unravel mechanistic investigations, including the accelerated adsorption and dissociation process of H2O on the Co‐O‐Cr moiety surface, the down‐shifted d‐band center, a lowered energy barrier for the OER and so on. This work offers a design direction for optimizing catalytic activity toward energy conversion. [ABSTRACT FROM AUTHOR]

Electrocatalysis is a potential method for sustainable hydrogen production, and the development of non‐noble metal‐based effective electrocatalysts for electrochemical water splitting is the core of exploiting and utilizing renewable energy. Herein, a stupendous electrocatalyst with multiheterostructure interfaces and 3D porous structure is synthesized, and the mechanisms of enhanced electrocatalytic activity combining multicharacterizations and density functional calculations are clarified. Especially, the fabricated Co2P/N@Ti3C2Tx@NF (denoted as CPN@TC) exhibits an ultralow overpotential of 15 mV to arrive at a current density of 10 mA cm−2 with the long‐term durability and a small Tafel slope of 30 mV dec−1 in 1 m KOH, which even compares with noble metal catalysts favorably. The outstanding HER activity is ascribed to multiheterointerfaces for adsorbing H2O and H*, fine conductivity for the electronic transmission, and well‐designed structure for rapid transport of ions and gases. It is reasonable to think that the synthetic strategy of CPN@TC can be extended to the preparation of transition‐metal‐based phosphides for enhanced catalytic performance. [ABSTRACT FROM AUTHOR]

It still remains a great challenge to develop alternative electrocatalysts with low cost, high efficiency and good stability for the hydrogen evolution reaction (HER). In this study, effectively conductive rGO (reduced graphene oxide) was used as the support both to promote charge transfer and to refine the particle size of WC, to realize efficient and stable HER performance. The facile in situ method can make highly dispersed WC nanoparticles firmly anchor onto the rGO substrate. Benefiting from its unique morphology and strong synergistic effect, the designed WC@rGO achieves a giant improvement in HER activity in both acidic and alkaline solutions compared with pristine WC. The overpotentials of WC@rGO are 2.82 and 2.30 times smaller than those of pristine WC to achieve 10 mA cm−2 in acid and alkaline solutions. More specifically, the Pt-modified WC electrocatalyst with negligible accumulation of Pt (4 wt%) even exhibits superior electrocatalytic performance (η10 and Tafel slope of 54 mV and 21 mV dec−1 in acid solution and 61 mV and 28 mV dec−1 in alkaline solution) to commercial 10 wt% Pt@C. The method reported in this study enables eco-friendly preparation of cheap, stable and effective HER electrodes. [ABSTRACT FROM AUTHOR]

In recent years, MOF-based materials, including pristine metal-organic frameworks (MOFs) and their derivatives, are one kind of the most popular materials, and have been widely used in biomedicine, sensing, energy storage, and catalysis due to their unique pore structures, abundantly accessible metal nodes, large specific surface areas, tailorable function, and morphology. Most of them have shown satisfactory performances in specific fields. However, there are still some urgent problems need to be solved in the application of MOF-based materials in electrocatalytic water splitting, especially the facile and controllable synthesis, and limited activity and stability. Herein, first this article mainly reviewed the applications and challenges of MOF-based materials in electrocatalytic water splitting. Then, typical development strategies (e.g., construction of multi-metallic site of MOF-based materials, structural morphology designing and controlling, engineering of doping, defect, vacancy, coupling with conductive carrier or constructing heterostructures) were highlighted in this review. Finally, perspectives on the development of MOF-based materials were provided for fabricating more efficient water splitting electrocatalysts. [Display omitted] • Different strategies to enhance the electrocatalytic performances of MOF-based materials are summarized. • Advantages of MOF-based materials in electrochemical water splitting are summarized. • The mechanisms of the enhanced catalytic activity are explored. • Some challenges and views for the future development of MOF-based materials are highlighted. [ABSTRACT FROM AUTHOR]