Spherical cationic polymer networks with porphyrin photosensitizer for sustainable and efficient photocatalysis

The continuous and sustainable photo-activity on micro- or nano-carriers has always been a key stepping stone in the industrialization of photo-catalysis, photo-synthesis, and photo-degradation. Herein, we report a new series of positively charged hollow microspheres carrying porphyrin moieties. Such hollow spheres are formed through crosslinking of well-ordered porous thin laminates, initiated by co-assembly of regular monomers and those decorated with porphyrin moieties. On the surface of an individual sphere, densely distributed positive sites attract anionic reactants. The superficial porphyrin decomposes the accumulated reactants under 1 Sun. After degradation and release of products, the photoactive sites are thereby renewed. We demonstrate that polymer network (1:10) exhibited superior sustainable photocatalytic performance with complete degradation of methyl orange (MO) in 40 min with no observable performance deterioration after six cycles. The established close loop of adsorption–reaction–release cycle makes possible many efficient and continuous photo-catalytic processes. © Tsinghua University Press 2023.