Bimetallic Metal-Organic Framework Derived ZnO/Ni0.9Zn0.1O Nanocomposites for Improved Photocatalytic Degradation of Organic Dyes

Abstract

An optimized structure is of considerable importance for nickle oxide (NiO)-based materials to achieve high performance as catalyst for contaminant degradation due to the inherent large band gap. Herein, a series of hybrids of NiO nanoparticles doped with zinc oxide (ZnO) semiconductor were fabricated via a facile one-step calcination of bimetallic metal-organic frameworks with varied Ni2+/Zn2+ molar ratios (MOF-NiZn). It is worth noting that partial positions of Ni in NiO lattice are replaced by Zn to form a Ni0.9Zn0.1O phase. Benefiting from the unique hybrid advantage, the rationally designed material could effectively lower the band gap of NiO, thus improving the photocatalytic performance. The optimized ZnO/Ni0.9Zn0.1O-82 catalyst exhibits the highest degradation activity towards methylene blue (MB) with efficiency up to 97.4 % within 60 min. Additionally, the radicals trapping experiments reveal that the photo-generated hydroxyl radical (.OH) is the predominant active species during the photodegradation of MB.