A new 0D-2D CsPbBr-CoO heterostructure photocatalyst with efficient charge separation for photocatalytic CO reduction

The effective spatial separation of photogenerated charge carriers is essential for realizing efficient CO 2 conversion. Herein, a new CsPbBr 3 -Co 3 O 4 heterostructure photocatalyst was rationally developed for photocatalytic CO 2 reduction. A facile synthetic strategy based on electrostatic interactions was utilized. The results revealed that the CsPbBr 3 -Co 3 O 4 hybrid exhibited a boosted evolution rate of 64.6 μmol g −1 h −1 (CO: 35.40 μmol g −1 h −1 ; CH 4 : 29.2 μmol g −1 h −1 ) with an electron consumption rate ( R electron ) of 304.4 μmol g −1 h −1 , surpassing pristine CsPbBr 3 or Co 3 O 4 . The high activity mainly arises from efficient charge separation and the directional transfer of electrons from CsPbBr 3 to Co 3 O 4 via an intimately coupled heterointerface. Notably, the surface features (derived from the unique morphology) expedited the CO 2 adsorption and accumulation of electrons at the Co 3 O 4 site which ultimately facilitated the conversion of CO 2 over the CsPbBr 3 -Co 3 O 4 composite. This approach provides a strategy to design and modulate highly active metal oxide and perovskite-based photocatalysts and presents great potential for constructing a heterointerface for CO 2 reduction. CsPbBr 3 quantum dots were precisely incorporated in Co 3 O 4 hexagonal platelets to construct a new CsPbBr 3 -Co 3 O 4 heterostructure, which exhibited efficient charge separation to achieve an improved photocatalytic reduction of CO 2 into CO and CH 4 .