Investigation of transition metal doped and polymer capped zno nanoparticles for photocatalytic antibacterial and corrosion applications

Abstract

Environmental hazards due to the industrial activities are quite increasing in our day today life. Various significant operations and approaches like clean-Tech, green chemistry, eco mark and so on were insisted for the sustainable future. The environmental cleaning process is being concentrated by various scientists using heterogeneous photocatalytic material. These materials not only applied for the degradation of the environmental pollutants discarded from the industries but also applied as an anticorrosive products that could prevent the corrosion of the metal by coating these heterogeneous nanocomposite materials over the metal products and it also may be applied as an antibacterial material. The present work was aimed to synthesize the semiconductors such as pristine ZnO, transition metal doped ZnO such as Cu(X) doped Zn(1-X)O ,Al(X) doped Zn(1-X)O, Mg(X) doped Zn(1-X)O, Mg(X), Al(Y) codoped Zn(1-X+Y)O, Mg(X),Ti(Y) codoped Zn(1-X+Y)O and polyvinyl pyrrolidone capped ZnO, chitosan capped ZnO NPs by a wet chemical method. The synthesized material was investigated for its structural confirmation using X-Ray power Diffraction (XRD), structural morphology from Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS), functional group determination by Fourier-Transform Infrared Spectroscopy (FTIR), optical property by Ultraviolet visible spectroscopy (UV-Vis) and Photoluminescence (PL). From the results, X-Ray diffraction studies revealed the formation of highly crystalline structures for ZnO, transition metal doped and polymers capped ZnO, the transition metals were found to be doped and polymers capped in ZnO matrices, whereas addition of transition metals like copper, aluminium, magnesium and titanium and polymers such as PVP and chitosan results from the formation of nanoparticles, instead of dopant as proved from XRD analysis. The SEM images of doped and capped ZnO with transition metals and polymers revealed nanostructured, spherically shaped and reduced sized nanoparticles whereas SEM images of pristine ZnO NPs exhibited a morphology of hexagonal-like appearance. EDAX results proved the substitution of transition metals and polymers in ZnO lattice. The presence of Cu, Al, Mg, Ti, PVP and chitosan in the nanoparticles is confirmed from EDAX analysis. FT-IR spectra revealed the occurrence of symmetric and asymmetric vibrations of carboxylate groups. As per the UVvisible analysis, Mg and Ti codoped ZnO enhanced the visible light absorption through the substantial shift of zinc oxide absorption edge to red. Also the photocatalytic competency of Mg and Ti codoped ZnO was promoted due to the decreased band gap as a result of increased tendency of electron excitation from ground state newline