Electrodeposition of wurtzite CdTe and the potential dependence of the phase structure

•CdTe films were electrodeposited from an alkaline solution.•WZ phase CdTe increased gradually with the positive shift of the potential.•The phase composition depends on the stoichiometry of CdTe film.•The phase transformation occurs during the thermal treatment.

CdTe solar cell is promising in high efficiency and low cost. Wurtzite CdTe is metastable and hard to prepare at high temperature. Herein, we electrodeposited CdTe film from an alkaline solution. The wurtzite structure was firstly found in the electrodeposited films. The film composition and phase structure varied much with deposition potential. Annealing causes the phase transformation from wurtzite to zinc blende. The crystallinity, density, and interface quality of CdTe films after annealing depend heavily on component and phase structure of the as-prepared films.