Co1-xCuxFe2O4 (0 ≤ x ≤ 0.5) nanoparticles were prepared by the microwave combustion technique. The obtained samples were characterized using X-ray diffraction (XRD) analysis, X-ray photoelectron spectroscopy (XPS), high resolution scanning electron microscopy (HR-SEM), energy dispersive X-ray (EDX) analysis, UV-visible diffuse reflectance spectroscopy, photoluminescence (PL) spectroscopy, Fourier transformed infrared (FT-IR) spectroscopy and vibrating sample magnetometry. The XRD result confirms the formation of cubic spinel structure and the average crystallite size was observed to be in the range of 46-31 nm calculated by Debye Scherrer's equation. XPS analysis was carried out to study the chemical elements and oxidation states of the synthesized Co1-xCuxFe2O4 (0 ≤ x ≤ 0.5) nanoparticles. The HR-SEM image showed agglomerated spherical nanoparticles and the elemental composition of copper doped cobalt ferrite was attained from energy dispersive X-ray analysis. The band gap energy was calculated by diffuse reflectance spectroscopy. Photoluminescence spectra showed the rate of recombination of electron-hole pairs and presence of defects. The band at 661 and 569 cm-1 is due to the intrinsic stretching vibrations of octahedral group complex of Co2+-O2- and Fe3+-O2- at tetrahedral sites. Remanence magnetization (Mr), coercivity (Hc) and saturation magnetization (Ms) were deduced from the hysteresis curves. The obtained Co1-xCuxFe2O4 (0 ≤ x ≤ 0.5) nanoparticles were assessed for the photocatalytic degradation of RhB under visible light. A possible mechanism responsible for photocatalytic degradation process is discussed. © 2017 Elsevier Ltd. All rights reserved.