The Au/ZnSe/ZnO Heterojunction Improves the Electron Transfer Behavior to Enhance the Detection Performance of Ascorbic Acid

Abstract The Au/ZnSe/ZnO heterojunction material with less transition zone on the two-phase interface was successfully prepared by the in-situ replacement of zinc oxide by Se2-. Moreover, the heterojunction formed by in-situ substitution can effectively reduce the interface transfer resistance and increase the life of carriers. The photocurrent of Au/ZnSe/ZnO is almost twice that of Au/ZnO, due to the formation of heterojunction ZnSe interface. As a result, the carrier lifetime of the material is increased by nearly 2.7 times (126.26 s/46.83 s) compared to Au/ZnO. Ascorbic acid is a very important compound for human metabolism, but there is no simple and rapid method to detect ascorbic acid. Au/ZnSe/ZnO is used as the photoanode of the photoelectric non-enzymatic sensor system for AA detection. The sensitivity of Au/ZnSe/ZnO/FTO-based PEC AA sensor is 113.75 μA·mM-1·cm-2, exhibiting its advantages of fast, sensitive and high response.