Cu/ZnO Nano-Thorn with Modifiable Morphology for Photoelectrochemical Detection of Glucose

Abstract

Enzyme free glucose detection is widely concerned because of its high stability and low cost, however, the sensitivity is relatively low in neutral solution. Compared with electrochemical sensor, photoelectrochemical sensor is more sensitive due to the independent excitation and detection source. Here, we present a Cu/ZnO nano-thorn array for photoelectrochemical detection to glucose in neutral solution，in which the uniform array structure and the Cu nanorod inside provide excellent conductivity, and the outside ZnO nanowire branches ensure large electrochemical active area. Moreover, the Schottky junction formed between the trunk of Cu nanorod and the branches of ZnO nanowires facilitates the separation of photogenerated electrons and holes. Therefore, the Cu/ZnO nano-thorn exhibits good photoactivity, which also shows an excellent performance in photoelectrochemical detection of glucose in neutral solution with a sensitivity of 63.76 μA mM−1 cm−2 in the range of 0.1–4.5 mmol l−1, and a limit detection of 3.762 μmol l−1.