Polyarene Oxides with Tunable Quinone Units for Photocatalytic CO Reduction: A Simple Strategy toward Effective and Selective Catalysts.

The photocatalytic transformation of carbon dioxide (CO) into valuable chemicals is a challenging process that requires effective and selective catalysts. However, most polymer-based photocatalysts with electron donor-acceptor (D-A) structures are synthesized with a fixed D-A ratio by using expensive monomers. Herein, we report a simple strategy to prepare polyarene oxides (PAOs) with quinone structural units via oxidation treatment of polyarene (PA). The resultant PAOs show tunable D-A structures and electronic band positions depending on the degree of oxidation, which can catalyze the photoreduction of CO with water under visible light irradiation, generating CO as the sole carbonaceous product without H generation. Especially, the PAO with an oxygen content of 17.6% afforded the highest CO production rate of 161.9 μmol g h. It is verified that the redox transformation between quinone and phenolic hydroxyl in PAOs achieves CO photoreduction coupled with water oxidation. This study provides a facile way to access conjugated polymers with a tunable D-A structure and demonstrates that the resultant PAOs are promising photocatalysts for CO reduction.