Structural Design and Electronic Modulation of Transition‐Metal‐Carbide Electrocatalysts toward Efficient Hydrogen Evolution

Abstract

As the key of hydrogen economy, electrocatalytic hydrogen evolution reactions (HERs) depend on the availability of cost-efficient electrocatalysts. Over the past years, there is a rapid rise in noble-metal-free electrocatalysts. Among them, transition metal carbides (TMCs) are highlighted due to their structural and electronic merits, e.g., high conductivity, metallic band states, tunable surface/bulk architectures, etc. Herein, representative efforts and progress made on TMCs are comprehensively reviewed, focusing on the noble-metal-like electronic configuration and the relevant structural/electronic modulation. Briefly, specific nanostructures and carbon-based hybrids are introduced to increase active-site abundance and to promote mass transportation, and heteroatom doping and heterointerface engineering are encouraged to optimize the chemical configurations of active sites toward intrinsically boosted HER kinetics. Finally, a perspective on the future development of TMC electrocatalysts is offered. The overall aim is to shed some light on the exploration of emerging materials in energy chemistry.

Reduced graphene oxide‐based materials for electrochemical energy conversion reactions

“…I, DFT‐calculated free energy diagrams for the electrochemical reduction of H + at the equilibrium potential for Pt, rGO, Fe 3 W 3 C, WC, Fe 3 W 3 C@rGO, and WC@rGO heterostructure. A‐I, Reprinted from Gao et al, Copyright 2019, with permission from Elesvier. DFT, density functional theory; HADDF, high‐angle annular dark‐field imaging; rGO, reduced graphene oxide; RHE, reversible hydrogen electrode; SEM, scanning electron microscope; STEM, scanning transmission electron microscope [Color figure can be viewed at wileyonlinelibrary.com]…”

Construction of Defect‐Rich Ni‐Fe‐Doped K0.23MnO2 Cubic Nanoflowers via Etching Prussian Blue Analogue for Efficient Overall Water Splitting

“…At present, the first‐ranked OER and HER catalysts are noble metal‐based materials with scarce earth abundance and costly prices, such as IrO 2 and RuO 2 (for OER) and Pt (for HER). Recently non‐noble metal‐based catalysts with remarkable OER or HER activity have been widely reported, for example, transition‐metal‐based oxides,2 hydroxides,3 phosphates,4 nitrides,5 carbides,6 and chalcogenides,7 etc. To save costs, simplify the synthetic process, and increase availability of catalysts, it is of benefit to develop bifunctional electrocatalysts for overall water splitting.…”

2D Stacks of MXene Ti3C2 and 1T‐Phase WS2 with Enhanced Capacitive Behavior

“…One of the very useful applications of these materials is in the electrochemical energy storage, where the advantage of 2D materials – large surface area – is fully utilized. Besides the transition metal dichalcogenides and graphene, 2‐D layered titanium carbide is also studied for its remarkable electrochemical properties . Ti 3 C 2 is a prototypical MXene, it was produced for the first time by etching of aluminum from Ti 3 AlC 2 MAX phase in 2011 (Scheme ).…”