Visible-Light-Active Iodide-Doped BiOBr Coatings for Sustainable Infrastructure

ACS Appl Mater Interfaces. 2023 Oct 25;15(42):49270-49280. doi: 10.1021/acsami.3c11525. Epub 2023 Oct 12.

Abstract

The search for efficient materials for sustainable infrastructure is an urgent challenge toward potential negative emission technologies and the global environmental crisis. Pleasant, efficient sunlight-activated coatings for applications in self-cleaning windows are sought in the glass industry, particularly those produced from scalable technologies. The current work presents visible-light-active iodide-doped BiOBr thin films fabricated using aerosol-assisted chemical vapor deposition. The impact of dopant concentration on the structural, morphological, and optical properties was studied systematically. The photocatalytic properties of the parent materials and as-deposited doped films were evaluated using the smart ink test. An optimized material was identified as containing 2.7 atom % iodide dopant. Insight into the photocatalytic behavior of these coatings was gathered from photoluminescence and photoelectrochemical studies. The optimum photocatalytic performance could be explained from a balance between photon absorption, charge generation, carrier separation, and charge transport properties under 450 nm irradiation. This optimized iodide-doped BiOBr coating is an excellent candidate for the photodegradation of volatile organic pollutants, with potential applications in self-cleaning windows and other surfaces.

Keywords: aerosol-assisted chemical vapor deposition (AACVD); iodide-doped BiOBr thin films; resazurin ink; self-cleaning windows; visible-light photocatalysis.