E. tirucalli plant latex mediated green combustion synthesis of ZnO nanoparticles: Structure, photoluminescence and photo-catalytic activities

ZnO nanoparticles were synthesized using esterases contained E. tirucalli plant latex as a fuel. The structural, morphological and spectroscopic studies of the as-synthesized ZnO nanoparticles were analyzed using powder X-ray Diffraction (PXRD), Fourier transform infrared spectroscopy (FTIR), UV-Visible absorption and photoluminescence (PL) spectroscopy. The structural parameters were refined by the Rietveld refinement method using PXRD data and confirmed that the prepared compound is pure hexagonal wurtzite structure with space group P63mc (No. 186). The average crystallite size was estimated by Scherrer's and WH plots and found to be in the range 17-23 and 20-26 nm respectively. The band gap of ZnO nanoparticles was estimated using Wood-Tauc relation and found to be in the range of 3.10-3.25 eV. PL studies revealed that a broad yellow emission peak appeared at 570 nm upon 380 nm excitation peaks. Photocatalytic degradation of Methylene blue (MB) dye was studied under UV irradiations. 5.5 ml of 5% esterases contained E. tirucalli plant latex used for the synthesis of ZnO shows 96% of degradation (5 × 10−5 M MB at pH 12). The prepared ZnO nanoparticles find application in optical and photo-catalytic degradations.