Abstract:
In recent years, nanoparticles synthesis by biological method has gained extensive attention due
to its low cost, simplicity, non-toxic and environmentally-friendly nature, compared with
chemical and physical synthesis methods. The aim of this study is to fabricate Aloe vera leaf
extract supported ZnO and Cu-doped ZnO nanoparticles for their photocatalytic and antibacterial
activities evaluation. ZnO and Cu-doped ZnO nanoparticles were prepared from zinc nitrate
hexahydrate and copper nitrate trihydrate using the plant extract. The synthesized nanoparticles
were characterized by using UV-Vis, FT-IR, XRD, and SEM spectroscopic techniques, and
tested as antibacterial and photocatalysts. The UV-Visible spectra showed absorbance peaks at
358 nm, 365 nm, and 379 nm, which correspond to the characteristic band of ZnO, 1% Cudoped
ZnO, and 4 % Cu-doped ZnO nanoparticles respectively. FT-IR confirmed the nature of
bonds and functional groups in the leaf extract, ZnO and Cu-doped nanoparticles. The XRD
analysis reveals all the synthesized particles have a crystalline nature with a particle size of
19.24 nm, 23.74 nm, and 24.91 nm of ZnO, 1% Cu-doped ZnO and 4% Cu-doped ZnO NPs
respectively. SEM image showed irregular, crushed-ice, and spherical shapes of the NPs. The
antibacterial activity studies of the synthesized 1% Cu- doped ZnO and 4 % Cu-doped ZnO Nps
against Staphylococcus aureus, Bacillus cereus, Escherichia. Coli and salmonella typhi showed
good potential with the reference to the selected standards Gentamicin and DMSO. The
maximum zone inhibition activities were found against gram-positive (B. cereus and S. aureus)
for 4% Cu-doped ZnO NPs followed by 1% Cu-doped ZnO NPs, whereas minimum inhibition
zone were seen against gram-negative (E.coli and S.typhi). 1% Cu-doped ZnO and 4% Cu-doped
ZnO NPs displayed good degradation efficiency, 78.48% and 88.07% respectively after 180 min
of irradiation, 4% Cu-doped ZnO NPs showing better photocatalytic efficiency.
