Efficient photosensitized singlet oxygen generation in two-dimensional perovskite nanosheets via energy transfer

Two-dimensional (2D) organic-inorganic hybrid halide perovskites have gained extensive attention in photovoltaics , photodetectors and light-emitting diodes owing to their unique optoelectronic properties and superior stability compared with their three-dimensional (3D) counterparts. However, 2D perovskites have rarely been applied for photochemical conversion applications. Herein, a series of 2D BA 2 MA n-1 Pb n Br 3n+1 perovskite nanosheets have been synthesized through a facile, ligand-free precipitation (LFP) method at room temperature . Using the specific chemical trapping techniques, we show for the first time that the 2D perovskite nanosheets can effectively generate photosensitized singlet oxygen ( 1 O 2 ) via energy transfer from triplet excitons to molecular oxygen in non-polar solvent. Based on this discovery, the as-prepared BA 2 PbBr 4 and BA 2 MAPb 2 Br 7 nanosheets successfully catalyze the ENE reaction and 1,2-addition reaction between olefin and singlet oxygen under visible light . Our study is anticipated to develop and demonstrate new mechanisms for 2D halide perovskite materials in photodynamic therapy and photocatalytic applications.