Glass-encapsulated CsPbBr3 nanocrystals incorporated with hollow bowl TiO2 nanoarrays towards efficient NO removal

Expanding light response is a significant approach to increase the harvesting efficiency of solar energy for photocatalysts. In this paper, aqueous CsPbBr 3 nanocrystals (NCs) were created using sol-gel glass as a reactor. These bright SiO 2 glass-coated NCs were decorated on hollow TiO 2 bowl array (TBN) via mechano-chemical pre-reaction and subsequent hydrothermal treatment for the first time to enhance the photocatalytic performance for NO removal. The homogeneous distribution of the NCs and the well-developed interface in type II CsPbBr 3 /TiO 2 heterostructures play important roles for improving the separation and transfer of photogenerated charge carriers. The light response of the CsPbBr 3 NCs increased the harvesting efficiency of solar energy. In addition, the bright photoluminescence of the CsPbBr 3 NCs was almost quenched to further confirm the separation of the photogenerated charge carriers in the heterostructures. Using optimized preparation conditions, the CsPbBr 3 /TiO 2 composite sample revealed an outstanding NO removal rate of 77.9 % at a concentration of 300 ppb, in which 45.2 % of NO was removed using pure TBN. In addition, the CsPbBr 3 /TiO 2 sample revealed excellent performance for photocatalytic H 2 O 2 evolution rate of 104.3 µM∙L −1 ∙h −1 , suggesting the CsPbBr 3 /TiO 2 composite can be applied for various photocatalytic fields. These results supplied new insights for the synthesis of photocatalysts and application of perovskite NCs.