Efficient and stable all-inorganic Sb_(2)(S,Se)_(3)solar cells via manipulating energy levels in MnS hole transporting layers

The use of organic hole transport layer(HTL)Spiro-OMeTAD in various solar cells imposes serious stabil-ity and cost problems,and thus calls for inorganic substitute materials.In this work,a novel inorganic MnS film prepared by thermal evaporation has been demonstrated to serve as a decent HTL in high-performance Sb_(2)(S,Se)_(3)solar cells,providing a cost-effective all-inorganic solution.A low-temperature air-annealing process for the evaporated MnS layer was found to result in a significant positive effect on the power conversion efficiency(PCE)of Sb_(2)(S,Se)_(3)solar cells,due to its better-matched energy band alignment after partial oxidation.Impressively,the device with the optimized MnS HTL has achieved an excellent PCE of about 9.24%,which is the highest efficiency among all-inorganic Sb_(2)(S,Se)_(3)solar cells.Our result has revealed that MnS is a feasible substitute for organic HTL in Sb-based solar cells to achieve high PCE,low cost,and high stability.

Front and Back contact engineering for high-efficient and low-cost hydrothermal derived Sb_(2)(S, Se)_(3) solar cells by using FTO/SnO_(2) and carbon

Antimony chalcogenide Sb_(2)(S, Se)_(3) is attracting a lot of attention as photovoltaic absorber owing to its rewarding photoelectric properties, low toxicity, and earth abundance. However, its device efficiency is still limited by the absorber material quality and device interface recombination. In this work, a fluorinedoped tin oxide(FTO) substrate with ultra-thin SnO_(2) layer and a low-cost stabilized carbon paste are introduced as a front and back contact layer respectively in Sb_(2)(S, Se)_(3) based planar solar cells. Over 5.2% efficiency is demonstrated in the structure of FTO/SnO_(2)/Cd S/Sb_(2)(S, Se)_3/Carbon/Ag, where the Sb_(2)(S, Se)_(3) is prepared by hydrothermal technique. The complementary device physics characterizations reveal that the interfacial recombination between TCO and Cd S is significantly suppressed by the introduction of ultra-thin SnO_(2) layer, which is profited from the leakage protection and bandgap offset engineering by its high resistivity and suitable conduction band minimum. Meanwhile, the successful adoption of the lowcost stabilized carbon as a back contact here shows an enormous potential to replace the conventional organic hole transport materials and noble metal. We hope this work can provide positive guidance to optimize Sb_(2)(S, Se)_(3) based planar solar cells in the future.