Amine-Functionalized Titanate Nanosheet-Assembled Yolk@Shell Microspheres for Efficient Cocatalyst-Free Visible-Light Photocatalytic CO2 Reduction

Exploiting advanced semiconductor photocatalyst with superior activity and selectivity for the conversion of CO2 into solar fuels and valuable chemicals is of worldwide interest. In this report, hierarchical amine-functionalized titanate nanosheets based yolk@shell microspheres were synthesized via one-pot organic amine mediated anhydrous alcoholysis of titanium(IV) butoxide. The selected organic amine, diethylenetriamine, played multiple roles. First, it was essential for the crystallographic, morphological and textural control of the synthesized titanate nanoarchitectures. Second, it was crucial for the in situ functionalization of titanate nanosheets by concurrent interlayer intercalation and surface grafting, which gave rise to the strong visible-light absorption ability and high CO2 adsorption capacity. As a consequence of the synergetic tuning in multilevel microstructures, an integrated engineering of the multifunctional modules of the titanate-based photocatalysts was achieved for efficient CO2 reduction toward solar fuels.