The Polymer Society of Korea

Abstract

Organic photoelectrochemical (PEC) devices based on bulk heterojunction (BHJ) photoactive layers are promising for sustainable hydrogen production. However, their operational stability in aqueous environments is severely limited by weak interactions between the organic layer and metal catalysts. This leads to the detachment of spray-coated catalysts during operation, particularly in photocathodes for the hydrogen evolution reaction (HER).
Here, we propose a molecular design strategy that reinforces the organic–catalyst interface by introducing hydrophilic side chains into polymer acceptors. The hydrophilic side chains contain electron-rich functional groups that can bind to exposed metal centers on metal oxide catalysts. This leads to the formation of stable interfacial coordination bonds and significantly enhances the adhesion between the organic layer and the catalyst suppressing catalyst agglomeration and detachment.