Hydrothermal Deposition and Further Simulative Optimization of Device Achieving Efficiency Close 19% for AgSbS2 Solar Cell.

As an emerging light-absorbing material, AgSbS2 attracts attention due to its excellent water and oxygen stability, environmental benign elemental composition, and high absorption coefficient. However, the reported highest power conversion efficiency (PCE) of AgSbS2 solar cell is only 2.25% due to the lack of suitable AgSbS2 thin film preparation strategy and systematic materials investigation toward improving the physical properties. Here a hydrothermal deposition method is developed for the fabrication of AgSbS2 films, which show large grain size and compact surface morphology. Planar heterojunction device structure is applied with improved electrical contact and carrier transport between the electron layer/light absorbing layer, which generates a PCE of 3.39%, representing the highest efficiency of this material. To explore the performance optimization direction of AgSbS2 photovoltaic devices, the device is numerically simulated. Finally, it is found that the PCE of AgSbS2 solar cells can reach 18.99% in theory, and the improvement of crystallinity and interface recombination state are the key methods to elevate its efficiency, which provides reference for the preparation of high-quality AgSbS2 film and further improvement of PCE.