Micelle assisted synthesis of La2O3 nanoparticles and their applications in photodegradation of bromophenol blue

Lanthanum Oxide (La2O3) nanoparticles were synthesized by precipitation method using alkylbenzyl dimethyl ammonium chloride (Benzalkonium chloride) surfactant. The critical micelle concentration (CMC) value of the surfactant was determined using conductance and surface tension methods. The nanoparticles were characterized using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), energy dispersive X-ray (EDX) and X-ray diffraction (XRD) analysis. Crystallite size and geometry of La2O3 nanoparticles, established through XRD, are 40 nm and hexagonal, respectively. The optical property was calculated using solid phase UV-visible absorption spectrophotometer with band gap of 4.2 eV. Photocatalytic efficiency of La2O3 nanoparticles was studied against bromophenolblue (organic pollutant) with and without UV radiations. Percentage degradation and first order rate constant values were determined as 24.7% and 0.0942 min(-1) without irradiation and that they were 50.4 % and 0.0941 min(-1)with irradiation, respectively.