Strategies for Improving the Photocatalytic Methane to Methanol Conversion Efficiency

The photocatalytic conversion of methane (CH4) into methanol (CH3OH) has evoked great interest recently. In this minireview, we summarize the recent advances and current status on how to construct efficient semiconductor-based photocatalysts for enhancing the CH4 conversion efficiency and selectivity to CH3OH. This minireview firstly introduces the different radicals induced photocatalytic CH4 conversion mechanisms. Then, different strategies proposed for improving the CH4-to-CH3OH performance are highlighted with some selected typical examples, including engineering surface defects, tuning size and morphology, doping with different ions, designing heterojunctions, decorating with cocatalysts, and assisting with oxidants. Finally, we give a concise perspective on the existing challenges and specifically propose further research opportunities on maximizing the photocatalytic performance for CH4 conversion. It is anticipated that this minireview could bring more fundamental insights into the design of advanced photocatalysts toward CH4 to CH3OH conversion under solar light irradiation.