Doping effects in Sb2S3 absorber for full-inorganic printed solar cells with 5.7% conversion efficiency

Ti, Zn, and Bi were doped into the Sb2S3 extremely thin absorber (ETA) of an all-solid-state, fully inorganic printed solar cell. Bi doping shifted the Sb2S3 absorption edge to longer wavelength and Bi-doped Sb2S3 was aggregated on the TiO2 electrodes, which resulted in photocurrent deterioration. In contrast, Ti and Zn doping did not shift the absorption edge, but improved the photocurrent. The best photocurrent density of 16.3 mA cm−2 was achieved with Ti doping (5 at% to Sb), resulting in the best conversion efficiency of 5.7%.