Antimony chalcogenide Sb2(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 fluorine-doped tin oxide (FTO) substrate with ultra-thin SnO2 layer and a low-cost stabilized carbon paste are introduced as a front and back contact layer respectively in Sb2(S,Se)3 based planar solar cells.Over 5.2% efficiency is demonstrated in the structure of FTO/SnO2/CdS/Sb2(S,Se)3/Carbon/Ag,where the Sb2(S,Se)3 is prepared by hydrothermal technique.The complementary device physics characterizations reveal that the interfacial recombination between TCO and CdS is significantly suppressed by the introduction of ultra-thin SnO2 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 low-cost 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 Sb2(S,Se)3 based planar solar cells in the future.