Photocatalytic Degradation of Rhodamine B Using MnO2 and ZnO Nanoparticles
The oxide semiconductor with different band gap energy i.e. manganese dioxide (MnO2) (Eg: 1.30eV) and zinc oxide (ZnO) (Eg: 3.37 eV) nanoparticles were used to degrade RhodamineB (RhB) under irradiation of UV light (254 nm).The MnO2 nanoparticles were synthesized by hydrothermal method (160 °C, 4 h) using analytical grade manganese sulfate hydrate and potassium permanganate (VII) as precursors. The XRD analysis reveals that the nanoparticles were d-MnO2.The photocatalytic study shows that degradation of RhB solution by ZnO nanoparticles (rate constant: 0.02749 min-1) was approximately four times faster than the d-MnO2 nanoparticles (rate constant:0.0067 min-1). This observation could be attributed to the higher reducing and oxidizing power of ZnO in producing free radicals for photodegradation of RhB solution.
Akrajas Ali Umar, Muhamad Mat Salleh and Muhammad Yahaya
Y. L. Chan et al., "Photocatalytic Degradation of Rhodamine B Using MnO2 and ZnO Nanoparticles", Materials Science Forum, Vol. 756, pp. 167-174, 2013