A new coordination complex of [Cd (2,2′-bipyridine)(dipic) (H2O)2]. 7H2O (dipic2− = pyridine 2,6-dicarboxylate) was synthesized under hydrothermal conditions. The crystal structure of Cd complex was characterized by X-ray diffraction. The results confirmed that the coordination geometry of Cd2+ is a distorted pentagonal bipyramid. The complex was evaluated as a catalyst for the peroxidation of cyclohexane. The oxidation reaction was performed under mild conditions by hydrogen peroxide at room temperature. In the absence of HNO3, Cd complex exhibits a maximum yield of 31%. CdO nanoparticles were synthesized through thermal analysis of Cd complex and identified by various techniques. The ability of CdO nanoparticles was investigated for the removal of Congo red (CR). The effects of contact time, adsorbent dosage, and pH were evaluated using batch method. Studies have shown that the uptake process is pseudo-second order. Also, the adsorption isotherm can be well fitted by the Langmuir model, while this process is spontaneous.