CuSbSe2photovoltaic devices with 3% efficiency

Recent technical and commercial successes of existing thin-film solar cell technologies encourage the exploration of next-generation photovoltaic (PV) absorber materials. Of particular scientific interest are compounds that do not exhibit conventional tetrahedral semiconductor bonding, such as CuSbSe 2 . CuSbSe 2 has a 1.1 eV optical absorption onset, a 10 5 cm −1 absorption coefficient, and a hole concentration of 10 17 cm −3 . Here, we demonstrate CuSbSe 2 PV prototypes with efficiencies >3%, prepared by a self-regulated sputtering process using a conventional substrate device architecture. Bulk recombination, device engineering issues, and a nonideal CuSbSe 2 /CdS band offset likely limit the promising initial result.