A Conductive Network and Dipole Field for Harnessing Photogenerated Charge Kinetics

Photogenerated charge separation and directional transfer to active sites are pivotal steps in photocatalysis, which limit the efficiency of redox reactions. Here, a conductive network and dipole field are employed to harness photogenerated charge kinetics by using a Ti₃ C₂ /TiO₂ network (TTN). The TTN exhibits a prolonged charge-carrier lifetime (1.026 ns) and an 11.76-fold increase in hexavalent chromium photoreduction reaction kinetics compared to TiO₂ nanoparticles (TiO₂ NPs). This super photocatalytic performance is derived from the efficient photogenerated charge kinetics, which is steered by the conductive network and dipole field. The conductivity enhancement of the TiO₂ network is achieved by continuous chemical bonds, which promotes electron-hole (e-h) separation. In addition, at the interface of Ti₃ C₂ and TiO₂ , band bending induced by the dipole field promotes photogenerated electron spatially directed transfer to the catalytic sites on Ti₃ C₂ . This study demonstrates that a conductive network and dipole field offer a new concept to harness charge kinetics for photocatalysis.