High-throughput bubble screening for rapid design of multi-component alloy catalysts for efficient oxygen evolution

Abstract

The sluggish four-electron oxygen evolution reaction (OER) with a high kinetic barrier remains the major bottleneck for industrial alkaline water electrolysis, motivating the development of efficient and durable non-noble metal catalysts. Multicomponent alloying offers a powerful route to tune OER-active sites through inter-element electronic interactions and synergistic redox chemistry. However, the enormous compositional space makes the rational optimization of elemental ratios labor-intensive and scientifically challenging. Here, we establish a product-bubble-based high-throughput screening strategy that directly correlates oxygen bubble evolution behavior with catalytic activity, enabling rapid identification of promising compositions from a continuously varied Al–Co–Ni–Fe–Mo multicomponent alloy library. Guided by this screening, we synthesize the target composition Al₃₂Co_37.5Ni_8.5Fe₁₀Mo₁₂ on nickel foam and further activate it via dealloying. Dealloying induces in situ reconstruction into vertically aligned nanosheet arrays, selectively leaches Al, enriches Co at the surface, and promotes the formation of high-valence metal species. As a result, the dealloyed sample delivers low overpotentials of 269 mV and 312 mV at 10 and 100 mA cm⁻² in 1.0 M KOH, respectively, and maintains stable operation at both current densities. This work provides a fast and intuitive pathway for screening and designing non-precious multicomponent OER catalysts with promising potential for practical water electrolysis applications.