Abstract A novel two-step sol–gel method was used i order to synthesize PbTiO3 nanoparticles with aid of Pb(CH3COO)22H2O, and Ti(OC4H9)4 (TNBT) as the starting reagents in the presence of ethanol as the solvent. To the best of authors knowledge, it is first time that benzene-1,3,5-tricarboxylic acid [C6H3(COOH)3] (trimesic acid) use as a chelate agent in produce lead titanate nanoparticles. Besides, to examine the effect of some reaction parameters such as surfactants, reaction temperature, and molar ratio of TNBT to trimesic acid on the morphology and chemical structure of final products several tests were performed. The as-synthesized PbTiO3 nanoparticle was utilized as photo-anode material for the fabrication of FTO/PbTiO3/CdS/Pt–FTO and photocatalyst for decolonization of rhodamine-B (RhB) and methylene blue (MB) to investigation its light harvesting applications. Furthermore, according to the XRD results, only in the presence of trimesic acid as the chelate agent pure PbTiO3 nanoparticle was synthesized. The photocatalyst results reveal that the maximum decolorization of 88 and 82 % for RhB and MB occurred with PbTiO3 nanoparticles catalyst in 40 min of stirring under ultraviolet light irradiation, respectively.