Encapsulated CdSe/CdS nanorods in double-shelled porous nanocomposites for efficient photocatalytic CO2 reduction

Abstract

Colloidal quantum dots have been emerging as promising photocatalysts to convert CO2 into fuels by using solar energy. However, the above photocatalysts usually suffer from low CO2 adsorption capacity because of their nonporous structures, which principally reduces their catalytic efficiency. Here, we show that synchronizing imine polycondensation reaction to self-assembly of colloidal CdSe/CdS nanorods can produce micro-meso hierarchically porous nanocomposites with double-shelled nanocomposites. Owing to their hierarchical pores and the ability to separate photoexcited electrons, the self-assembled porous nanocomposites exhibit remarkably higher activity (≈ 64.6 μmol g−1 h−1) toward CO2 to CO in solid-gas regime than that of nonporous solids from self-assembled CdSe/CdS nanorods under identical conditions. Importantly, the length of the nanorods is demonstrated to be crucial to correlate their ability to long-distance separation of photogenerated electrons and holes along their axial direction. Overall, this approach provides a rational strategy to optimize the CO2 adsorption and conversion by integrating the inorganic and organic semiconductors.