Cu2Te solar cells fabricated by printing

Cu2Te particles were synthesised by ball milling and then printed on an In2S3/TiO2/FTO-glass substrate, resulting in superstrate-structured solar cells. The as-prepared Cu2Te particles were amorphous, but their crystallinity was improved after annealing at 400-650 degrees C. The Cu2Te particles annealed at 400 degrees C, melted partially, and a completely melted Cu2Te film was obtained at annealing temperatures of 600-650 degrees C. The band gap of the Cu2Te films annealed at 400-600 degrees C was approximately 0.8 eV. The photovoltaic characteristics of the best full Cu2Te cells were as follows: short-circuit current, 21 mA/cm(2); open-circuit voltage, 0.24 V; fill factor, 0.3; and energy conversion efficiency, 1.57%. Thus, Cu2Te with its low melting point and high photocurrent is a promising candidate absorber layer for solar cell applications.