# Synthesis and photocatalytic activity of CeO2-NbC-x catalysts for degrading oxytetracycline in aquaculture water bodies

## TL;DR

This study develops a new catalyst, CeO2-NbC-x, that efficiently degrades the antibiotic oxytetracycline in aquaculture water under light.

## Contribution

A novel photocatalytic mechanism and high-performance CeO2-NbC-x catalyst for antibiotic degradation in water.

## Key findings

- The CeO2-NbC-x catalyst achieved 99% degradation of oxytetracycline under optimal conditions.
- The catalyst shows strong ultraviolet and visible light absorption.
- A new photocatalytic mechanism was proposed based on band arrangement and capture experiments.

## Abstract

The aquaculture water body is rich in antibiotics, which has caused great harm to the natural environment. It is urgent to adopt special means to degrade antibiotics from the source and reduce their impact on human production and life. In this study, the CeO2@NbC (CeO2-NbC-x (where x denotes the wt% of NbC)) catalyst was synthesized by the molten salt method, polyacrylamide gel method and heat treatment technology. Multiple characterization methods confirmed that there were no other impurities in the CeO2-NbC-x catalyst, and a special contact was formed between the CeO2 and NbC interfaces. The CeO2-NbC-x catalyst exhibits high ultraviolet and visible light optical absorption coefficients. Using oxytetracycline hydrochloride as the target pollutant, the effects of catalyst concentration, pollutant concentration and pH value on the photocatalytic activity of the CeO2-NbC-x catalyst were investigated. When the catalyst concentration, pollutant concentration and pH value were 2 g/L, 75 mg/L, and 5, respectively, the degradation percentage of CeO2-NbC-x catalyst reached 99%. Based on capture experiments and band arrangement theory, a new photocatalytic mechanism of the CeO2-NbC-x catalyst has been proposed. This research provides new ideas for the application of wide bandgap semiconductors couple semiconductors with metallic properties in the field of photocatalysis.