Effect of design modification on efficiency enhancement in Sb2S3 absorber based solar cell

The effect of tailored architecture and interfacial engineering on efficiency enhancement-3.5 times vis-`a-vis experimental value in Sb2S3 absorber based solar cell is reported. It is attributed to design driven lowered interfacial recombination for identical absorber based solar cell. The design modification comprises optimal intrinsic layer insertion, carrier density control, absorber bandgap widening, Fermi level pinning and back surface field at Sb2S3/metal junction. Hole carrier density lowering and band gap engineering near Sb2S3/CdS junction and interfacial recombination lowering improved short circuit current (-90%), open circuit voltage (-67%), fill factor (-15%) and efficiency (-255%). The simulation analysis confirmed that CdS buffer layer donor defects pinned the Fermi level near conduction band edge at Sb2S3/CdS interface causing lower recom-bination. A high hole concentration thin layer at Sb2S3/metal interface also reduced back contact interfacial recombination. Modified solar cell architecture confirmed possibility of chalcogenide solar cell having enhanced efficiency-16% vis-`a-vis 4.5% reported in literature.