Multimetallenes and their electrocatalytic applications

Abstract

As a core driving force for energy conversion and storage, electrochemical catalytic technology has an irreplaceable strategic position in realizing the goal of carbon neutrality. However, it is still limited by bottlenecks such as low catalytic activity, selectivity and stability. In this context, multimetallenes have become a new platform to overcome the above bottlenecks by virtue of their ultra-high specific surface area, tunable electronic properties, and synergistic effects of multiple components brought about by atomic-level thickness. However, the current research hotspots still focus on monometallene systems, and the development of multimetallenes is limited by the core problems such as compositional segregation due to the differences in the reduction kinetics of the multivariate precursors, the difficulty of controllable synthesis of high-entropy systems, and the unknown mechanism of the dynamic evolution of the active sites under the complex working conditions, which seriously restrict their practical application performance under high current density and harsh conditions. This review systematically compiles the latest progress in this field: first, focusing on the innovation of controllable synthesis strategies, detailing the methods of surface energy-regulated reduction growth, hard template-limited domain thermally driven co-reduction, and self-template-assisted step-by-step alloying, aiming at solving the problem of multimetallene homogeneity and realizing precise construction; second, in-depth discussion of the optimization of multi-dimensional structural modification, covering the defect engineering, lattice strain modulation, polyalloying, non-metallene doping, heterogeneous interface design, surface functionalization, etc., to finely regulate the electronic and geometric structures of the materials and significantly enhance the reaction kinetics and durability; finally, in terms of application expansion, we focus on the breakthroughs of its performance in high-current density scenarios, such as oxygen reduction, all-water decomposition, small-molecule electro-oxidation/coupling, and CO₂ reduction. The aim of this paper is to provide comprehensive guidance for the design of highly efficient and stable multimetallene-based electrode materials, to promote their large-scale application in high-performance membrane electrode devices and integrated energy systems, to accelerate the industrialization of electrochemical conversion technologies, and to help achieve the goal of carbon neutrality.