Niobium Oxide for Microplastics Degradation—the Effect of Crystal Structure and Morphology

Abstract

Microplastic (MP) pollution is ubiquitous in the environment and there is a significant need for the development of photocatalysts for environmental remediation of microplastic pollution. Herein, the effect of the structure and morphology of Nb2O5 nanostructures on their photocatalytic activity for MP degradation is investigated. Nanostructures with a high fraction of pseudohexagonal TT-Nb2O5 phase are shown to effectively degrade pure polyethylene, polypropylene, and polyester, as well as MP samples collected from the environment. Efficient photocatalytic degradation of the microplastics is attributed to the unique structure and morphology (TT-Nb2O5 nanoparticles on monoclinic Nb2O5 rods), which facilitates charge separation and consequently photocatalytic activity. The Nb2O5 nanostructures with optimal composition and morphology lead to efficient degradation of not only pure plastic particles with different compositions (polyethylene, polypropylene, and polyester) in up to 64 h, but also complete degradation of environmental microplastics in 56 h.