Antibacterial and photocatalytic activity of Tb-doped ZnO nanoparticles: effect of doping concentration

Tb-doped ZnO nanoparticles (Tb_xZn_1-xO) were prepared by chemical precipitation method with different doping concentrations of Tb. The crystallite size and other related structural properties are examined. Young’s modulus, electron jump length and crystal lattice distortion degree are discussed as a function of doping concentration. The band gap reduces from 3.24 to 2.82 eV as the doping concentration of Tb increases from 0%. The prepared nanoparticles are hole-rich materials. The quenching is observed in the photoluminescence spectrum due to doping. Kirby–Bauer method is employed to investigate the anti-bacterial activity against Gram-positive and Gram-negative bacteria that cause septicemia. The degradation of methylene blue using the prepared nanoparticles as a catalyst is examined using both UV and Visible radiation. The effective degradation is observed in this work and the enhanced photocatalytic activity is observed at high doping concentration of Tb. The maximum degradation efficiency of 98.60% is observed against methylene blue when the dye is irradiated by UV radiation for the time period of 120 min. But the same is 74.89% by visible light.