Nanoscale calcium bismuth mixed oxide with enhanced photocatalytic performance under visible light

The objective of materials research is the development of economical, safe and efficient synthesis routes that lead to the formation of a photocatalyst which is able to overcome performance problems related to particle size, crystallinity, or low surface area. Here, we report high-quality functional nanoparticles of calcium bismuth mixed oxide with 15 nm nominal size corresponding to a specific surface area of 41 m2/g which were produced by single-step flame spray synthesis (FSS). The high temperature of the flame afforded creation of oxygen vacancies which were quantified by near edge X-ray absorption fine structure (NEXAFS) spectra. These two parameters, developed active surface area and created in the flame oxygen vacancies, allowed to enhance the photocatalytic activity of calcium bismuth oxide by a factor of 6, in comparison to previously reported calcium bismuth mixed oxide produced by conventional methods which required additional temperature treatment steps.

A significant decrease in particle size of calcium bismuth mixed oxide, a promising photocatalyst has been achieved by a single-step flame spray synthesis. This provided high-quality functional nanoparticles nominally 15 nm in size, with a specific surface area of 41 m2/g. The preparation route afforded oxygen vacancies which enhanced the photocatalytic activity of calcium bismuth oxide and extended the absorption spectrum to the visible region.Figure optionsDownload high-quality image (35 K)Download as PowerPoint slide