Carbon and nitrogen co-doped TiO2 nanotube photocatalysts were synthesized by hydrothermal sol-gel method using the precursors of tetrabutyl titanate

glucose and urea for the dopant sources of titanium

carbon and N elements

respectively. Subsequently

characterization on the structure of catalysts was conducted and the photocatalytic performance for chlorobenzene (CB) conversion reactions was evaluated. Response surface methodology (RSM) was employed to investigate the effects of molar ratios of C to Ti and N to Ti on the catalytic activities

and the optimum ratios of 0.49 and 0.28 for the catalyst (donated as 0.5C/0.3N-TiO2) were achieved. Characterizations on the structure and morphology of catalysts were conducted by XRD and TEM techniques. In combination with UV-vis spectra

FI-IR and BET techniques

it suggested that carbon and nitrogen co-doped titania consists of anatase and rutile with larger surface area

of which the UV-vis absorption spectra were red-shifted to 500 nm of wavelength. Under conditions of 10% of relative humidity

50 mg·m-3 of initial concentration and 60 s of reaction time

the conversion ratio of CB reached 93.5%. The catalyst exhibited a relatively high removal ratio (over 80%) of CB under relative humidity ranging from 10% to 60%. Durability test showed the catalytic activities of CB conversion reactions slightly reduced after continuous running for over 10 h of reaction time.