Lead antimony sulfides are rare in nature and relatively unexplored ternary semiconductors. This work investigates the photovoltaic performance of Pb-Sb-S quantum dot-sensitized solar cells (QDSCs). Pb5Sb8S17 nanoparticles are grown on mesoporous TiO2 electrodes using the successive ionic layer adsorption reaction process. The synthesized Pb5Sb8S17 nanoparticles exhibit two attractive features for a good solar absorber material: a high optical absorption coefficient and a near optimal energy gap. Solid-state QDSCs are fabricated from the synthesized Pb5Sb8S17 nanoparticles using Spiro-OMeTAD as the hole-transporting material. The best cell yields a short-circuit current density J(sc) of 11.92 mA cm(-2), an open-circuit voltage V-oc of 0.48 V, a fill factor FF of 30.7% and a power conversion efficiency (PCE) of 1.76% under 1sun. The external quantum efficiency (EQE) spectrum covers a spectral range of 350-800 nm with a maximal EQE = 65% at lambda = 450 nm. At the reduced light intensity of 10% sun, the PCE increases to 4.14% with J(sc) = 2.0 mA cm(-2) (which could be normalized to 20 mA cm(-2) under 1 sun). This PCE is 65% higher than the best previous result. The respectable PCE and J(sc) indicate that Pb5Sb8S17 could be a potential candidate for a solar absorber material. (C) 2016 Elsevier B.V. All rights reserved.