Cubic-cubic perovskite quantum dots/PbS mixed dimensional materials for highly efficient CO2 reduction

Abstract The mixed dimensional materials, especially 0D/2D mixed materials have been regarded as outstanding candidates for photodetector and photovoltaic devices, while have rarely been utilized for photocatalytic reactions including photosynthesis, water splitting and CO2 reduction. In this work, a mixed dimensional material composited by cubic 0D CsPbBr3 perovskite quantum dots (PQDs) and cubic 2D-PbS is prepared for reduction of CO2 to fuels. The PQDs, as light-harvesting components, are homogeneously grown on the 2D-PbS nano-substrate which is employed for electron transport. The same cubic crystal structures and rather small lattice mismatch ( Δ d / d CsPbBr 3 = 0.84 % ) between CsPbBr3 and PbS guarantee easy in-situ growth of PQDs on PbS nano-substrate and rapid electron migration. As a result, an improved photocurrent is obtained based on the combination of the advantages of 0D and 2D materials. In addition, the size of PQDs synthesized on the 2D-PbS is dramatically reduced in comparison to that synthesized in solvent, thus endowing them wider bandgap and greater potential enough for the photocatalytic reactions. This PQDs/2D-PbS mixed dimensional materials exhibit outstanding selectivity (over 99%) and activity (yield 81.6 and 52.7 μmol g−1) for reducing CO2 to CO and CH4, from which the CH4 yielded is ca. 9-fold than that of pure PQDs.