Polyarene Oxides with Tunable Quinone Units for Photocatalytic CO 2 Reduction: A Simple Strategy toward Effective and Selective Catalysts.

The photocatalytic transformation of carbon dioxide (CO 2 ) 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 2 with water under visible light irradiation, generating CO as the sole carbonaceous product without H 2 generation. Especially, the PAO with an oxygen content of 17.6% afforded the highest CO production rate of 161.9 μmol g -1 h -1 . It is verified that the redox transformation between quinone and phenolic hydroxyl in PAOs achieves CO 2 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 2 reduction.