Influence of irradiation on stability and effectiveness of TiO 2 /N,C photocatalysts

Abstract

The gypsum building material was enriched with photocatalytic properties for indoor air purification. The photocatalytic additive to gypsum was TiO2 modified with carbon from various sources. The photocatalytic activity of gypsum plates was performed towards NO x removal. Carbon doping into TiO2 improved not only total degradation of NO x on corresponding gypsum plates but also NO2 selectivity was changed, limiting the production of toxic NO2. The exhibition of photocatalysts on the visible and ultraviolet irradiation has been also carried out to examine their durability. First, the stability of modifying element – carbon in TiO2 structure was analysed, indicating on the gradual reduction of carbon content with irradiation time, especially when the carbon source was cyclic hydrocarbon. Second, the photocatalytic activity of the gypsum plates was performed at each stage of the ageing process. Based on this insight, the correlation between carbon content in modified photocatalysts loaded to gypsum plates and photocatalytic activity of them was described in detail.