Photocatalytic Degradation of Rhodamine B Using 1D CuO/TiO₂ Nanofibers Synthesized via the Electrospinning Method

This research was designed to improve the separation efficiency of photogenerated carriers in TiO₂ through the construction of a PN heterojunction. The motivation behind this was to tackle the problems of the narrow light response range and the high electron-hole recombination rate of TiO₂. By simple one-step implementing electrospinning and calcination procedures, CuO/TiO₂ PN heterojunction nanofibers were successfully synthesized. XRD and SEM analyses confirm that the heterojunction is a nanofiber structure composed of TiO₂ and CuO, with the TiO₂ containing anatase and rutile phases. The PL reveals that the fluorescence intensity of the heterojunction is lower compared to that of pure TiO₂, and this implies a remarkable enhancement in the carrier separation efficiency. Under xenon light irradiation, for the optimized sample, the degradation rate of RhB exceeds 80%. This degradation rate is 68% higher than that of pure TiO₂. The improvement in photocatalytic performance can be ascribed to the efficient charge separation driven by the built-in electric field within the PN junction and the extended light absorption range. The photoelectrochemical test further verified that the photocurrent density of the heterojunction system was 52.42% higher than that of the single TiO₂, providing a new strategy for designing efficient photocatalytic systems.