Continuous photo-oxidation of methane to methanol at an atomically tailored reticular gas-solid interface

Abstract

Photo-oxidation of methane (CH₄) using hydrogen peroxide (H₂O₂) synthesized in situ from air and water under sunlight offers an attractive route for producing green methanol while storing intermittent solar energy. However, in commonly used aqueous-phase systems, photocatalysis efficiency is severely limited due to the ultralow availability of CH₄ gas and H₂O₂ intermediate at the flooded interface. Here, we report an atomically modified metal-organic framework (MOF) membrane nanoreactor that promotes direct CH₄ photo-oxidation to methanol at the gas-solid interface in a reticular open framework. We show that the domino synergy between colocalized single-atom palladium and iron on MOF nodes enables efficient generation and in situ utilization of H₂O₂ in the absence of liquid water, thus circumventing H₂O₂ dilution. Meanwhile, the “breathable” MOF membrane, optimized by solar-driven interfacial water management, provides high-flux channels to facilitate efficient gas diffusion and rapid methanol desorption and transfer. As a result, we demonstrate over 210 hours of continuous photosynthesis of 0.25 M methanol with unity selectivity, achieving an exceptional methanol productivity of 14.4 millimoles per gram of catalyst per hour.