The surfactant-assisted synthesis of tantalum oxide nanoparticles (Ta2O5), its subsequent nitridation to form tantalum nitride (Ta3N5), and the evaluation of the photoactivity of these nanoparticles, are presented. The surface, optical, and compositional characterization of the in-house synthesized photocatalysts indicate spherical nanoparticles with phi = 30 nm Ta2O5 and phi = 30 nm Ta3N5 with the latter photocatalysts showing absorbance onset at similar to 630 nm. Photoelectrochemical analysis of the various photocatalyst films using chronoamperometry, linear sweep voltammetry, and impedance measurements attribute an improved photoactivity with the in-house catalysts to better charge generation, transport, and utilization. Initial results using Ta2O5 and Ta3N5 demonstrate photocatalytic activity toward conversion of colored pollutants. (C) The Author(s) 2019. Published by ECS.