Photodynamic and Photoelectrochemical Properties of Few-Layered Bismuthene Film on SnO2 Electrode and Its Hybridization with C60

Bismuthene, an exfoliated two-dimensional material obtained from bulk bismuth, has attracted a great deal of attention because of its unique electronic and spintronic properties. In this study, few-layered bismuthene (FLBi) with an average thickness of 1.0 nm was prepared by the successive ball mill and sonication method. The FLBi film was easily prepared onto a semiconducting SnO2 electrode by electrophoretic deposition (SnO2/FLBi). In the flash-photolysis time-resolved microwave conductivity (FP-TRMC) measurement, the SnO2/FLBi film revealed a rise of conductivity upon photoexcitation, demonstrating the occurrence of the electron injection from the photoexcited FLBi to the conduction band of SnO2. The SnO2/FLBi on a transparent fluorine-doped tin oxide (FTO) electrode was applied to photoelectrochemical devices. Photocurrents generated by the FTO/SnO2/FLBi electrode were higher than those generated by the FTO/SnO2 and FTO/FLBi electrodes owing to the efficient electron injection. In addition, inorganic FLBi was noncovalently functionalized with organic fullerene, that is, C-60 in a mixed solvent of toluene and acetonitrile. Upon photoexcitation, the hybrid composite of FLBi and C-60 predominantly caused photoinduced energy transfer from C-60 to FLBi without producing the charge-separated state. These findings provide basic insights into the feasibility toward the construction of FLBi-based optoelectronic devices.

Automated summary

Bismuthene, a two-dimensional material obtained from bulk bismuth, was successfully prepared and applied onto a semiconducting SnO2 electrode, demonstrating an increase in conductivity upon photoexcitation. Furthermore, the hybrid composite of FLBi and C-60 showed photoinduced energy transfer without producing the charge-separated state, showing potential for constructing optoelectronic devices.