Enhancement of photocatalytic aerobic oxidation of benzyl alcohol with the incorporation of cobalt in Zn-based MOF via post-synthetic metal exchange

In this work to introduce Co(II) ions into TMU-22(Zn) metal–organic framework (MOF), we report a postsynthetic exchange (PSE) approach. Several analytical methods were employed to examine the exchange between Co2+ ions and Zn2+ ions in TMU-22(Zn) for the formation of the mixed-metal TMU-22(Zn/Co). It was found that the introduction of active Co2+ ions into the TMU-22(Zn) framework leads to the photocatalytic activity of TMU-22(Zn/Co) for benzyl alcohol oxidation. Since Co2+ ions were favorably substituted at positions more accessible to the substrate, the TMU-22(Zn/Co) showed superior catalytic performance. This study provides a facile method to develop mixed-metal MOFs for photocatalysis performance.