The photosynthetic overall reaction represents a highly attractive and challenging research direction. Polyoxometalate-cellulose hybrid artificial leaves can improve photosynthetic activity by directed charge transport. At present, the overall reaction is confined to the interaction of gases with liquids, involving micro-substrate conversion in the same reaction system. In this paper, we report on a membranous polyoxometalate-based artificial leaf (3 %Ru3SiW12@cellulose) that efficiently performs 5-hydroxymethylfurfural oxidation coupled with furfural and CO2 reduction, exhibiting high selectivity across two spatially separate reaction systems. Notably, the photocatalysis and charge separation efficiency, facilitated by the regulation of cellulose, have significantly increased, positioning this approach at the forefront of photocatalyst research. Crucially, the artificial leaf is capable of light absorption, charge separation, charge storage, and energy release, allowing for the spatial and temporal decoupling of light and dark reactions. Overall, this study proposes a novel strategy for the development of a promising polyoxometalate-based reaction system with enhanced solar energy utilization.