Competent visible light driven photocatalytic removal of gaseous styrene over TiO2/g-C3N4: Characterization, parameters, kinetics, mechanism

•The best styrene photocatalytic degradation was achieved by 20wt%TiO2/g-C3N4.•g-C3N4 doped TiO2 reduced band gap and rate of electron-hole pair recombination.•20wt%TiO2/g-C3N4 elevated hydrophobicity and benefitted for styrene adsorption.•High relative humidity reduced photocatalytic activity from competitive adsorption. Removal of volatile organic compounds (VOCs), including styrene, via photocatalytic oxidation is preferable. The photocatalytic activity of g-C3N4 and TiO2 are limited by its fast recombination rate and wide band gap, respectively. This study examined improvement in photocatalytic degradation of styrene using g-C3N4 after doping with various proportions of TiO2. The best photocatalyst were also tested under various conditions (retention time, relative humidity, styrene concentration, and temperature) prior to study of reaction kinetics. 20 wt% TiO2/g-C3N4 presented the best styrene conversion and supported by characterization result. Formation of narrow band gap reached to 2.68 eV enhanced the performance of doped g-C3N4. Langmuir Hinshelwood model 4 presented a well fitted result with the experimental data. [Display omitted]