Interfacial Acid Sites‐Mediated ZnO‐Based Electrocatalysts for Sustainable Dual‐Pathway H 2 O 2 Production and Rechargeable Zn‐H
Lijun Yang, Sitong Liu, Wencheng He, Fengzhan Sun, Shubing Bi, Hongge Pan, Lingfeng Zhu, Tianyi Ma, Lei ZhangABSTRACT
Facing the challenge of achieving efficient and sustainable hydrogen peroxide (H 2 O 2 ) production, a promising strategy is developing highly selective electrocatalysts with controllable synthesis, structural design and performance optimization. Herein, an interfacial acid sites‐mediated ZnSe/ZnO heterojunction is synthesized for highly selective two‐electron oxygen reduction reaction (ORR) toward H 2 O 2 production. Experimental and theoretical results reveal that surface selenization induced reconstruction, forming a synergistic interface with a built‐in electric field and tailored oxygen vacancies (Ovs), which collaboratively optimize the electronic structure and accelerate reaction kinetics of two‐electron ORR. Moreover, interfacial unsaturated Zn 2+ sites and OVs served as Lewis acids sites to enhance O 2 adsorption and activation, while Br ø nsted acids sites were liable to donate protons to promote *OOH formation. Consequently, a ZnSe/ZnO ‖ ZnO flow cell enabled paired electrolysis for concurrent H 2 O 2 production with a high H 2 O 2 yield of 754.4 M g cat −1 over 12 h. A rechargeable Zn‐H 2 O 2 cell using ZnSe/ZnO cathode delivered a power density of 11.99 mW cm −2 as a self‐sustaining process for simultaneous on‐site H 2 O 2 production and electrical energy generation. This work offers a sustainable route for on‐site H 2 O 2 synthesis with improved energy efficiency, advancing green chemistry and circular economy.