Prohibiting the electron-phonon coupling effect in tungsten trioxide nanosheet colloid with enhanced photocatalytic...

The serious combination of abundant electrons/holes in bulk primarily hinders the efficiency in the photocatalytic reaction. It is crucial to control the spatial charge dynamics through delicately designing the crystal configuration of photocatalyst. In this work, a modified tungsten trioxide nanosheet colloid (M-WO₃) was synthesized by an ion exchange method. Compared to pristine WO₃ (P-WO₃), the crystal lattice vibration frequency of M-WO₃ increases from 2.8 meV to 4.3 meV, which effectively prohibits electron-phonon coupling and powerfully accelerates the separation and transfer of photoinduced charge carriers. Irradiated by visible-light, M-WO₃ shows much higher photocatalytic bacterial inactivation performance than P-WO₃. In addition, this regulation method increases the surface charges of the WO₃ colloid to improve its stability, which endows this colloid photocatalyst with broad prospects in practical photocatalytic antibacterial applications. This work offers guidance to construct efficiently separated photoinduced electron/hole pairs of the colloid photocatalyst by designing its crystal structure.