Non-noble Metal Single-Molecule Photocatalysts for the Overall Photosynthesis of Hydrogen Peroxide
Fan Fu, Yongxin Liu, Mingliang Liu, Zhengguang Li, Wanying Zhong, Yaqin Li, Kaixiu Li, Jun Wang, Yongchao Huang, Yiming Li, Wei Liu, Yi Zhang, Kaisong Xiang, Hui Liu, Pingshan Wang, Die Liu
Abstract
Despite the great progress in molecule photocatalytic solar energy conversion, it is particularly challenging to realize a photocatalytic overall reaction in a non-noble metal complex, which represents a new paradigm for photosynthesis. In this study, a class of novel non-noble metal complexes with head-to-tail geometry were designed and readily synthesized via the coordination of triphenylamine-modified 2,2′: 6′,2″-terpyridine ligands with Zn 2+ . As expected, these complexes exhibited the desired through-space charge-transfer transition, generating both long-lived excited states (on the order of microseconds) and separate redox centers under visible-light irradiation. These complexes have particularly low exciton binding energies, which make them excellent heterogeneous single molecular photocatalysts for the overall photosynthetic production of H 2 O 2 . Remarkably, a high H 2 O 2 evolution rate (8862 μmol g –1 h –1 ) was achieved in pure H 2 O under an air atmosphere via precise molecular tailoring, revealing the unparalleled advantages of molecular photocatalysts in improving the catalytic rate of H 2 O 2 production. This is the first time that single-molecule photocatalysts have been used to efficiently complete the photosynthesis of H 2 O 2 . This study presents a new paradigm for photocatalytic energy conversion and provides unique insights into the design of molecular photocatalysts.