A Computation-Guided Design of Highly Defined and Dense Bimetallic Active Sites on a Two-Dimensional Conductive Metal-Organic Framework for Efficient HO Electrosynthesis.

Electrochemical synthesis of hydrogen peroxide (HO) via the two-electron oxygen reduction reaction (2e-ORR) provides an alternative method to the energy-intensive anthraquinone method. Metal macrocycles with precise coordination are widely used for 2e-ORR electrocatalysis, but they have to be commonly loaded on conductive substrates, thus exposing a large number of 2e-ORR-inactive sites that result in poor HO production rate and efficiency. Herein, guided by first-principle predictions, a substrate-free and two-dimensional conductive metal-organic framework (Ni-TCPP(Co)), composed of CoN sites in porphine(Co) centers and NiO nodes, is designed as a multi-site catalyst for HO electrosynthesis. The approperiate distance between the CoN and NiO sites in Ni-TCPP(Co) weakens the electron transfer between them, thus ensuring their inherent activities and creating high-density active sites. Meanwhile, the intrinsic electronic conductivity and porosity of Ni-TCPP(Co) further facilitate rapid reaction kinetics. Therefore, outstanding 2e-ORR electrocatalytic performance has been achieved in both alkaline and neutral electrolytes (>90 %/85 % HO selectivity within 0-0.8 V vs. RHE and >18.2/18.0 mol g h HO yield under alkaline/neutral conditions), with confirmed feasibility for water purification and disinfection applications. This strategy thus provides a new avenue for designing catalysts with precise coordination and high-density active sites, promoting high-efficiency electrosynthesis of HO and beyond.