Photocatalytic degradation of volatile organic compounds using nanocomposite of P-type and N-type transition metal semiconductors

Volatile organic compounds (VOCs) are the main causes of poor indoor quality. It has been reported that the presence of VOCs in an indoor environment causes several acute respiratory health issues and also increases the risk of cancer. Over the past several years, various mechanisms have been proposed for VOCs removal from indoor environments. Nanoscale photocatalyst-based air purifying technologies have been popular in recent years. These technologies are based on photocatalytic oxidation process. The ability of this method to mineralize VOCs into carbon dioxide and water is its main attractive feature. Titanium oxide-based photo-catalysts have been commonly used for this purpose mainly because of their stability, corrosion resistance, and non-toxicity. However, its high excitation energy, low electron transfer rate to oxygen, and high recombination rate of electron/hole pair limit its photocatalytic performance in the UV–visible (UV–Vis) range. In this research, the authors built a photoreactor fitted with polyurethane foams coated with a corrosion-resistant nanocomposite to degrade VOCs in the presence of ultraviolet and visible light. The material is prepared through the sol–gel method. It is characterized by conducting the Fourier transform infrared spectroscopy, X-ray diffraction, and UV–Vis absorption spectrometry, and scanning electron microscope analysis. The efficiency of the photocatalyst was measured by observing acetone decay within the custom-made chamber. In all, 86.24% reduction in acetone concentration was observed. The results showed that the nanocomposite is capable of degrading the test VOC. Further research needs to be conducted to optimize the nanocomposite to make it commercially viable.