Enhanced photoelectric performance of Cu2-xSe nanostructure by doping with In3+

In3+ doped Cu2-xSe nanostructures have been successfully synthesized on a flexible carboxyl functionalized multi-walled carbon nanotubes/polyimide (COOH-MWCNTs/PI) membrane substrate by an electrochemical codeposition method. In this work, the focus was on the effect of different In3+ doping concentrations upon the morphological, structural, optical and photoelectrical properties of Cu2-xSe. Two different kinds of nanostructures, nanoflowers and nanolayers, were obtained. The crystallinity of Cu2-xSe was improved by doping with In3+. The atomic ratio of Cu, Se in Cu2-xSe nanolayers is about 1.85 : 1.00, and the atomic % of In is 1.32, confirming the presence of indium. The optical absorption intensity increased with an increase in the doping content of indium ions. However, In3+ had no effect upon the band gap and absorption edge. The effect of In3+ dopant on the photoelectric properties was investigated by photocurrent-time and current-voltage (I-V) measurements, which demonstrated that the photoelectric properties of Cu2-xSe were improved by doping with In3+. This result is significant for the fabrication of optoelectronic nanomaterials and photodetectors based on In3+-doped Cu2-xSe nanoflowers and nanolayers.