In situ formed nickel tungsten oxide amorphous layer on metal-organic framework derived ZnNiWO surface by self-reconstruction for acid hydrogen evolution reaction.

Noble metal free electrocatalysts for hydrogen evolution reaction (HER) in acid play an important role in proton exchange membrane-based electrolysis. Here, we develop an in situ surface self-reconstruction strategy to construct excellent acidic HER catalysts. Firstly, free-standing zinc nickel tungstate nanosheets inlaid with nickel tungsten alloy nanoparticles were synthesized on carbon cloth as pre-catalyst via metal-organic framework derived method.

Axial Oxygen Ligands Regulating Electronic and Geometric Structure of Zn-N-C Sites to Boost Oxygen Reduction Reaction.

Zn-N-C possesses the intrinsic inertia for Fenton-like reaction and can retain robust durability in harsh circumstance, but it is often neglected in oxygen reduction reaction (ORR) because of its poor catalytic activity. Zn is of fully filled 3d 4s configuration and is prone to evaporation, making it difficult to regulate the electronic and geometric structure of Zn center. Here, guided by theoretical calculations, five-fold coordinated single-atom Zn sites with four in-plane N ligands is constructed and one axial O ligand (Zn-N -O) by ionic liquid-assisted molten salt template method.

Constructing Pure Phase Tungsten-Based Bimetallic Carbide Nanosheet as an Efficient Bifunctional Electrocatalyst for Overall Water Splitting.

Carbides are commonly regarded as efficient hydrogen evolution reaction (HER) catalysts, but their poor oxygen evolution reaction (OER) catalytic activities seriously limit their practical application in overall water splitting. Here, vertically aligned porous cobalt tungsten carbide nanosheet embedded in N-doped carbon matrix (Co W C@NC) is successfully constructed on flexible carbon cloth (CC) as an efficient bifunctional electrocatalyst for overall water splitting via a facile metal-organic framework (MOF) derived method. The synergistic effect of Co and W atoms effectively tailors the electron state of carbide, optimizing the hydrogen-binding energy.

Design Superior Alkaline Hydrogen Evolution Electrocatalyst by Engineering Dual Active Sites for Water Dissociation and Hydrogen Desorption.

In alkaline media, the water-dissociation-related Volmer process always suppresses the hydrogen formation/desorption process, which makes it challenging to develop non-noble-metal alkaline electrocatalysts with excellent catalytic activity. Here, we proposed a two-pronged strategy to simultaneously promote the kinetic process of both water dissociation and hydrogen desorption with the Co-doped WO/amorphous CoW hybrid electrocatalyst. Impressively, the optimized hybrid exhibits an outstanding hydrogen evolution reaction (HER) activity with the quite small Tafel slope of 19.

Electronic Structure and Crystalline Phase Dual Modulation via Anion-Cation Co-doping for Boosting Oxygen Evolution with Long-Term Stability Under Large Current Density.

Designing a state-of-the-art nonprecious oxygen evolution reaction (OER) electrocatalyst with ultralong stability under high current density (≥100 h under 1000 mA cm) is greatly desirable for the viable electrolysis of water. The synthesis of nanostructure catalysts is an effective method for improving the OER performance, but nanostructure-based catalysts are easily destroyed by mechanical force via the vigorous oxygen gas evolution process at a high current density. Herein, we present a facile strategy of N-anion and Fe-cation dual doping to construct a three-dimensional self-supported nickel selenide film-based catalyst via a one-step chemical vapor deposition process.