Abstract
Carbon-doped titanium oxide (C/Ti–O) films were prepared on Si(100) wafer, stainless steel (type 304) and glass by reactive magnetron sputtering (RMS) using CO2 gas as carbon and oxygen source under room temperature (RT). X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) were used to analyze structure and composition of the as-prepared C/Ti–O film. It could be observed from XRD that the as-prepared C/Ti–O film contained TiO crystal phase structure. Ti2p XPS spectrum of the as-prepared C/Ti–O film showed that the valences of titanium were made up of Ti2+, Ti3+ and Ti4+. C1s XPS spectrum revealed that carbon was doped into titanium oxide based on the existence of the typical Ti–C bond. The optical absorption curve by ultraviolet–visible (UV–Vis) spectrophotometer showed that the C/Ti–O film appeared the remarkable red shift of absorption edge, which contributed to C substitution in O sites in amorphous TiO2. Photocatalysis test using methyl orange (MO) as indicator confirmed that the as-prepared C/Ti–O film had photocatalytic activity. Combined with the results of the tests and first-principles calculations, a potential photocatalysis mechanism was proposed.