Fotokatalytický rozklad N2O v přítomnosti nanokompozitů g-C3N4/TiO2 připravených nekonvenční metodou

Abstract

This work is focused on photocatalytic decomposition of nitrous oxide in the presence of nanocomposites TiO2/g-C3N4 prepared by unconventional method. The main purpose of the photocatalytic decomposition of nitrous oxide was its transformation to the natural components of environment - nitrogen and oxygen. Photocatalytic decomposition of nitrous oxide was carried out in batch reactor in the presence of photocatalysts (TiO2, TiO2/g-C3N4 (1:1), TiO2/g-C3N4 (1:2), TiO2/g-C3N4 (1:3), g-C3N4). 8 W Hg lamp with wavelength 365 nm was used as the source of irradiation, which was placed on a quartz glass window. The influence of ratios of TiO2 and g-C3N4 on conversion of nitrous oxide was monitored at the time intervals of 0 - 20 hours. Based on experimental data we can say that all photocatalysts showed a higher photoactivity than pure TiO2 and pure g-C3N4. The conversion of nitrous oxide decreased in this order: TiO2/g-C3N4 (1:3) < TiO2/g-C3N4 (1:2) < TiO2/g-C3N4 (1:1) < g-C3N4 < TiO2. The highest conversion of N2O (70,6 % after 20 hours irradiation) was achieved in the presence of nanocomposite TiO2/g-C3N4 with weight ratio 1:3, which was determined as the optimal ratio of TiO2 and g-C3N4. The creation of heterojunction in nanocomposites TiO2/g-C3N4 played the key role in activity of photocatalysts due to better separation of generated electrons and holes, and thereby the efficiency of photocatalytic reactions was increased.