Efficient room temperature aqueous Sb₂S₃ synthesis for inorganic-organic sensitized solar cells with 5.1% efficiencies

Sb₂S₃ sensitized solar cells are a promising alternative to devices employing organic dyes. The manufacture of Sb₂S₃ absorber layers is however slow and cumbersome. Here, we report the modified aqueous chemical bath synthesis of Sb₂S₃ absorber layers for sensitized solar cells. Our method is based on the hydrolysis of SbCl₃ to complex antimony ions decelerating the reaction at ambient conditions, in contrast to the usual low temperature deposition protocol. This simplified deposition route allows the manufacture of sensitized mesoporous-TiO₂ solar cells with power conversion efficiencies up to η = 5.1%. Photothermal deflection spectroscopy shows that the sub-bandgap trap-state density is lower in Sb₂S₃ films deposited with this method, compared to standard deposition protocols.