Preparation and first-principles study for electronic structures of BiOI/BiOCl composites with highly improved photocatalytic and adsorption performances

•Synthesis of BiOI/BiOCl via ionic liquid assisted ultrasonic method at room temperature.•High photoactivities for the degradation of organic pollutants under visible light irradiation.•Composite electronic structures of was explicated by a first-principles investigation.

The BiOI/BiOCl composites with high photocatalyitic and adsorption ablities were prepared via a facile ionic liquid assisted ultrasonic method in several hours at room temperature. The BiOI/BiOCl composites with different contents of BiOI can be conveniently synthesized via changing the amount of 1-ethyl-3-methylimidazolium iodide precursor during the preparation process. Microstructures, morphologies, porosities and bandgaps of the as-prepared samples were determined through various experimental methods. A first-principles calculation was employed to explicate electronic structures of the complex. Photocatalytic results suggest that the obtained BiOI/BiOCl composite with 40% BiOI has the highest photoactivity for the degradation of rhodamine-B and quinoline blue under visible light irradiation. All the rhodamine-B and quinoline blue can be degraded in 25 min and 15 min, respectively. To observe the universality of the BiOI/BiOCl, the degradation results of colorless target pollutant (tetracycline) was also investigated. Based on experimental and computational results, origins of the photocatalytic abilities leading to the observed results were proposed.

Graphical abstractBiOI/BiOCl composites with highly improved photocatalytic and adsorption performances were preapred via a facile method namely ionic liquid assisted ultrasonic method in several hours at room temperature.Figure optionsDownload full-size imageDownload high-quality image (183 K)Download as PowerPoint slide