Recycling and Recovery of Deactivated CsPbBr3 Perovskite after Photocatalytic CO2 Reduction Reaction

CsPbBr3 perovskite nanocrystals have emergedas promisingcandidates for photocatalysis. However, their conversion efficiencyis hampered by material instability, and the accumulation of deactivatedperovskites produced after photocatalytic reactions raises significantenvironmental concerns. To address this issue, we developed a mechanochemicalgrinding approach assisted by oleylamine as an additive to restorethe optical properties and photocatalytic activity of deactivatedCsPbBr(3), which was due to aggregation in the photocatalyticCO(2) reduction reaction. Upon regeneration, the CsPbBr3 nanocrystals exhibited an average length of 34.21 nm andan average width of 20.86 nm, demonstrating optical properties comparableto those of the pristine CsPbBr3 nanocrystals. Moreover,they achieved a conversion efficiency of 88.7% compared with pristineCsPbBr(3) nanocrystals in the photocatalytic CO2 reduction reaction. This method effectively enhanced the utilizationof CsPbBr3, offering a novel approach for the recyclingand recovery of perovskite materials and thereby minimizing materialwaste and environmental pollution.