Improved photocatalytic activity for degradation of methylene blue dye using ZnO NPs

We present a plant-mediated green synthesized bare ZnO and Ni–ZnO NPs (nanoparticles) employing soursop leaf extract. The plant extract was treated with 0.1 M of Zn (NO₃)₂·6H₂O The ZnO NPs have a wurtzite structure, according to XRD measurements. The mean size of the ZnO and Ni–ZnO NPs was examined to be 47.64 and 48.18 nm using an X-ray diffraction (XRD) pattern. The UV–visible spectrum displays absorbance maxima at 335 and 340 nm, which corresponds to an energy band gap of 3.28 and 3.24 eV for ZnO and Ni–ZnO NPs. Morphology studies show that the NPs are very permeable. The PL spectra of NPs revealed extremely intriguing blue, green, and red emissions following excitation at 391, 491 and 545 nm for ZnO and Ni–ZnO NPs, respectively. When exposed to UV light, the NPs exhibit photocatalytic efficacy for the reduction of methylene blue (MB) dye.