Carbon Modified TiO2 Photocatalyst with Enhanced Adsorptivity for Dyes from Water

A new photocatalyst was obtained by modification of commercial anatase TiO2 (Police, Poland) in a pressure reactor in an ethanol atmosphere at 120 °C for 4 h. The photocatalytic activity of the new material was tested during three azo dyes decomposition: monoazo (Reactive Red 198), diazo (Reactive Black 5) and poliazodye (Direct Green 99). The obtained photocatalyst had new bands at 1,440 cm−1 attributed to CO groups. UV–Vis/DR spectra of the photocatalyst also were changing and had an insignificant decrease in the visible region of the spectra. The amount of hydroxyl radicals produced on carbon-modified TiO2 was a little higher than for the pristine one. The carbon modification also changes the Freundlich model of dyes adsorption to Langmuir model of adsorption. Additionally, it increases the monolayer capacity of modified TiO2. As a result we observed a clear increase of the photocatalytic activity of carbon-modified TiO2 sample.