Famatinite Cu3SbS4 nanocrystals as hole transporting material for efficient perovskite solar cells

To overcome the weakness of the organic hole transporting material in perovskite solar cells (PSCs), we developed inorganic copper antimony sulfide (Cu3SbS4) nanocrystals as a hole transporting material (HTM) for PSCs by a hot-injection and spray-deposition technique. We proved that the Cu3SbS4 nanocrystal layer can enhance hole injection inhibiting the charge-carrier recombination within the perovskite layer. A power conversion efficiency (PCE) of 8.7% was obtained for the Cu3SbS4-based devices with improved stability. This work offers a new route which employs copper antimony sulfide compounds as hole transporting materials for efficient and stable perovskite solar cells.