An efficient strategy for the partial oxidation of methane into methanol over POM-immobilized MOF catalysts under ambient conditions

Abstract

One of the scientific obstacles in the direct conversion of methane to methanol lies in how to improve product selectivity. A dark photocatalysis mode that decouples solar energy in the dark may effectively alleviate this challenge. Herein, a range of composites had been prepared in which Fe-BTC was employed as the gas enrichment unit, while phosphotungstic acid (PTA) acted mainly as an electron storage within the framework. The modified reaction system allowed for the achievement of methanol yields up to 968 μmol·gcat−1·h−1 under ambient conditions. Besides extrinsic factors, such as a gentle reaction environment and avoidance of the oxidation reactions between photogenerated holes and alcohols, we also demonstrated through in situ EPR measurements that the introduced PTA effectively regulated •OH radicals and suppressed their further reaction with methanol. Moreover, the strategy demonstrated its universality by effectively enhancing the performance of other POM-immobilized MOF composites. This work opens a new path for the efficient and targeted conversion of inert methane to methanol.