Antimony sulfide-selenide solid solutions offer optical band gaps, E_g, in the 1–1.88 eV interval; and lead selenide offers E_g upward of its bulk value, 0.28 eV, depending on the extent of quantum confinement. In this work, thin film solar cells of SnO₂:F/CdS/Sb₂(Se/S)₃/PbSe/C-Ag are developed by chemical deposition of the thin films on transparent conductive oxide (TCO) glass. To prepare the solar cell, first a CdS thin film of 100 nm in thickness is deposited on the TCO from a solution containing Cd(II)-citrate complex. On this, a thin film is deposited from a solution containing potassium-antimony tartrate, thioacetamide and selenosulfate, which upon heating at 280°C in nitrogen ambient results in a Sb₂S_1.2Se_1.8 film of 150 nm in thickness with an E_g of 1.67 eV. PbSe thin film 110 nm in thickness is deposited on it from a solution of Pb-citrate complex and selenosulfate, with crystalline grain diameter 10 nm, and E_g of 1.86 eV. The cell shows open circuit voltage (V_oc), 454 mV, short circuit current density (J_sc) 12.5 mA/cm², fill factor (FF) 0.44 and conversion efficiency (η) 2.5%. The observed cell parameters are backed by a tentative energy level diagram and an estimate for the light generated current density.