Highly Ordered Conductive Metal‐Organic Frameworks with Chemically Confined Polyoxometalate Clusters: A Dual‐Functional Electrocatalyst for Efficient H<sub>2</sub>O<sub>2</sub> Synthesis and Biomass Valorization
Tong Bao, You Wu, Chencheng Tang, Yamin Xi, Yingying Zou, Pengyue Shan, Chaoqi Zhang, Wojciech Drożd, Artur R. Stefankiewicz, Pei Yuan, Chengzhong Yu, Chao Liu
Abstract
Abstract The design of bifunctional and high‐performance electrocatalysts that can be used as both cathodes and anodes for the two‐electron oxygen reduction reaction (2e − ORR) and biomass valorization is attracting increasing attention. Herein, a conserved ligand replacement strategy is developed for the synthesis of highly ordered conductive metal‐organic frameworks (Ni‐HITP, HITP = 2, 3, 6, 7, 10, 11‐hexaiminotriphenylene) with chemically confined phosphotungstic acid (PW 12 ) nanoclusters in the nanopores. The newly formed Ni−O−W bonds in the resultant Ni‐HITP/PW 12 electrocatalysts modulate the electronic structures of both Ni and W sites, which are favorable for cathodic 2e − ORR to H 2 O 2 production and anodic 5‐hydroxymethylfurfural oxidation reaction (HMFOR) to 2, 5‐furandicarboxylic acid (FDCA), respectively. In combination with the deliberately retained conductive frameworks and ordered pores, the dual‐functional Ni‐HITP/PW 12 composites enable a H 2 O 2 production rate of 9.51 mol g cat −1 h −1 and an FDCA yield of 96.8% at a current density of 100 mA cm −2 /cell voltage of 1.38 V in an integrated 2e − ORR/HMFOR system, significantly improved than the traditional 2e − ORR/oxygen evolution reaction system. This work has provided new insights into the rational design of advanced electrocatalysts and electrocatalytic systems for the green synthesis of valuable chemicals.