WO3/Pt photocatalyst supported by a ceramic filter for indoor air purification under visible light irradiation†

Abstract

Household air pollution exposure can lead to various diseases, including stroke, ischaemic heart disease, chronic obstructive pulmonary disease (COPD), and lung cancer. In this study, an indoor air purification technique was developed employing a visible light-activated photocatalyst consisting of a WO₃/Pt-coated ceramic foam filter (CFF). Under visible light irradiation, the coated porous filter was able to decompose toluene, a prevalent indoor air contaminant. The interconnected three-dimensional structure of the CFF with open pores facilitated toluene adsorption and simultaneous decomposition by the photocatalyst. XRD analysis revealed that WO₃/Pt had tungsten oxide in a monoclinic crystal structure with immiscible platinum metal clusters. The specific surface area and pore diameter were analyzed using the BET method, while the energy band gap was determined using DRS. XRF spectroscopy was used to find the percentage composition of the material, and structural and morphological studies of the samples were conducted using TEM and FESEM analyses. Photodegradation studies were performed for toluene removal, demonstrating a significant drop in toluene concentration in a short period (99.1% degradation in 150 min). A comparative investigation of the visible light photoactivity of WO₃/Pt and TiO₂ (P25) in water was conducted utilizing dye degradation tests, and WO₃/Pt dominated with its excellent degradation efficiency.