Hierarchically Mesoporous o-Hydroxyazobenzene Polymers: Synthesis and Their Applications in CO₂Capture and Conversion

The synthesis of hierarchically mesoporous polymers with multiple functionalities is challenging. Herein we reported a template-free strategy for synthesis of phenolic azo-polymers with hierarchical porous structures based on diazo-coupling reaction in aqueous solution under mild conditions. The resultant polymers have surface areas up to 593 m²g⁻¹with the mesopore ratio of >80 %, and a good ability to complex with metal ions, such as Cu²⁺, Zn²⁺,Ni²⁺, achieving a metal loading up to 26.24 wt %. Moreover, the polymers complexed with Zn showed excellent performance for catalyzing the reaction of CO₂with epoxide, affording a TOF of 2570 h⁻¹in the presence of tetrabutyl ammonium bromide (7.2 mol %). The polymer complexed with Cu could catalyze the oxidation of alcohol with high efficiency.