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Updated: May 9, 2026
Developing Photosensitizer-Cobaloxime Hybrids for Solar-Driven H2 Production in Aqueous Aerobic Conditions
Published on: October 5, 2019
Coordination orientation isomerism boosting concerted hydrogen peroxide photosynthesis
Aiguo Kong1, Yue Chen2, Yingying Zou2
1School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, PR China. agkong@chem.ecnu.edu.cn.
Abstract:
Designing isomers and elucidating their structure-property relationships are central to advancing chemistry and materials science. Two one-dimensional coordination polymers featuring dual scandium-salen centers are prepared as coordination orientation isomers, sharing identical composition but adopting distinct zigzag or linear chain structures. The zigzag isomer achieves a hydrogen peroxide photosynthesis rate of 0.390 mol gcat.-1 h-1 in an aqueous system employing 1,2,3,4-tetrahydroisoquinoline as sacrificial agent under full-spectrum light, while the linear isomer shows lower activity. A concerted mechanism is revealed, involving co-activation of oxygen and the organic donor through direct proton-coupled electron transfer. The zigzag architecture enhances charge separation via a stronger built-in electric field and stabilizes key co-activation intermediates. In this work, we show that constructing isomeric coordination polymers with tailored spatial and electronic structures provides an avenue for advancing artificial photosynthesis.
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