Empowering multicomponent alloys with unique nanostructure for exceptional oxygen evolution performance through self-replenishment

Context & scaleThe catalytic activity of oxygen evolution reaction (OER) materials is endowed by their optimized electronic structure, which enables active sites in the "activated state" to exchange electrons with intermediates rapidly. However, stability requires the materials to be in an "inert state" with limited or even no electron exchange with electrolytes to prevent corrosion. Therefore, activity always compromises the long-term durability of existing catalysts. Most strategies to improve their stability are usually at the expense of activity, and vice versa.Herein, we propose a counterintuitive concept to solve the aforementioned trade-off via integrating two parallel microscopic mechanisms in high-entropy alloys with two-layered nanostructures. The outer high-entropy amorphous oxide layer endows compelling OER activity, whereas the underneath layer affords dynamic replenishment capability for sustainable performance (over 1,600 h at 500 mA cm−2) in alkaline electrolytes.Highlights•Overcoming the trade-off between activity and stability of the OER•Discovering a replenishment mechanism to achieve the long-term stability•Established implementing parallel-mechanism strategy•Realizing low cost and mass productionSummaryOxygen evolution reaction (OER) catalysts suffer from degradation under harsh oxygen evolution conditions, especially at large current densities, which is a longstanding challenge when developing OER catalysts for industrial applications. Here, we report ultra-stable multicomponent alloys with outstanding OER performance, created by forming two-layered nanostructures in noble metal-free multicomponent alloys, which boost activity and stability simultaneously through a counterintuitive parallel-mechanism strategy. The outer multicomponent amorphous oxide layer endows compelling OER activity, while the underneath layer affords dynamic replenishment capability for sustainable performance (working stably at least 1,600 h at 500 mA cm−2) in alkaline electrolytes. More appealing is that the catalyst can be easily revitalized, significantly extending its service durability and reducing its cost. This finding can be applied to develop other cost-efficient catalysts with considerable potential for industrial applications, offering a design paradigm to break the activity-stability trade-off of electrocatalysts.Graphical abstract