Metal oxynitrides adopting the perovskite structure have been shown to be visible light-activated photocatalysts, and therefore, they have potential as self-cleaning materials where surface organic pollutants can be removed by photomineralization. In this work, we establish a route for the deposition of thin films for seven perovskite oxynitrides, CaTaO 2 N, SrTaO 2 N, BaTaO 2 N, LaTaON 2 , EuTaO 2 N, SrNbO 2 N, and LaNbON 2 , on quartz and alumina substrates using dip-coating of a polymer gel to form an amorphous oxide precursor film, followed by ammonolysis. The initially deposited oxide films were annealed at 800 °C, followed by ammonolysis at temperatures from 850 to 1000 °C. The perovskite oxynitride thin films were characterized using XRD and EDX, with band gaps determined using Tauc plots derived from UV−vis spectroscopic data. A cobalt oxide co-catalyst was deposited onto each film by drop casting, and the photocatalytic activity assessed under visible light using dichloroindophenol dye degradation in the presence of a sacrificial oxidant. The light source used was a solar simulator equipped with a 400 nm cut-off filter. The dye degradation test demonstrated photocatalytic activity in all samples except EuTaO 2 N and BaTaO 2 N. The three most active samples were SrNbO 2 N, CaTaO 2 N, and SrTaO 2 N. The cobalt oxide loading was optimized for these three films and found to be 0.3 μg cm −2 . Further, catalytic tests were conducted using stearic acid degradation, and this found the film of SrNbO 2 N with the cobalt oxide co-catalyst to be the most active for complete mineralization of this model pollutant.

Nine members of two contiguous solid solutions, Ba3Sc2-xInxO5Cu2S2 and Ba3In2O5¬Cu2S2-ySey (x, y = 0. 0.5, 1, 1.5 and 2), were synthesised at temperatures between 800 °C and 900 °C by...

Organic pollutants in water are a major concern for the environment and human health, and require urgent attention. Here, we developed for the first time monolithic structures by 3D printing...

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