Efficient Sb₂S₃-sensitized solar cells via single-step deposition of Sb₂S₃ using S/Sb-ratio-controlled SbCl₃-thiourea complex solution

To replace the conventional chemical bath deposition method, which is time-consuming and has a high impurity level, a chemical single-step deposition process employing a S/Sb ratio-controlled SbCl₃-thiourea complex solution is introduced to load Sb₂S₃ into a mesoporous TiO₂ electrode. This technique enables the fabrication of efficient and reproducible Sb₂S₃-sensitzed inorganic-organic heterojunction hybrid solar cells with hole-conducting conjugated polymers. The most efficient cell exhibits a short-circuit current density of 16.1 mA cm^-2, an open circuit voltage of 595.5 mV, and a fill factor of 66.5%, yielding a power conversion efficiency of ≈6.4% at standard AM1.5G condition (100 mW cm^-2). A single-step solution approach based on SbCl₃-thiourea complex solution processing is introduced for high-efficiency Sb₂S₃-sensitized solar cells. The Sb₂S₃ is easily deposited on substrates using S/Sb-ratio-controlled SbCl₃-thiourea complex solution. The champion device exhibits an overall power conversion efficiency of 6.4% under standard 1.5G conditions.