直流反应磁控溅射方法制备碳掺杂TiO2薄膜及其可见光活性

室温下通过直流反应磁控溅射的方法, 利用碳钛镶嵌靶在Ar/O2气氛中制备了碳掺杂纳米TiO2薄膜, 并通过X射线衍射(XRD)、UV-Vis透射光谱以及光电化学的方法对薄膜进行了表征. XRD测试结果表明, 靶中碳和钛的面积比小于0.10时, 碳掺杂的引入有利于TiO2薄膜的晶格生长, 并随靶中碳面积的增加, 薄膜的结晶度也相应提高. 由透射光谱计算得到的禁带宽度表明, 靶中碳和钛的面积比为0.05时, 薄膜的禁带宽度由纯TiO2薄膜的3.4 eV减小到3.1 eV. 光电测试结果表明, 靶中碳和钛的面积比小于0.10时, 碳的引入可以提高薄膜的光电响应, 面积比为0.10时, 可见光下0 V时薄膜的光电流密度为0.069 μA·cm-2; 但碳和钛的面积比增加到0.16时, 测得的薄膜光电响应异常.

Visible Light Photoelectrochemical Response of Carbon-doped TiO2 Thin Films Prepared by DC Reactive Magnetron Sputtering

Carbon-doped TiO2 thin films were prepared by direct current (DC) reactive magnetron sputtering at room temperature in an Ar/O2 ambience, using a titanium target incrusted with graphite pieces. The films as prepared were characterized by X-ray diffraction (XRD), UV-Vis transmission spectra, and photoelectrochemistry methods. The XRD patterns of the films showed that the doping of carbon was beneficial to the crystallization of the films. When the ratio of area of C/Ti in the target was less than 0.10, the crystallization of the films increased with the increase in graphite area in the target. The band gap of the films decreased from 3.4 eV to 3.1 eV when the ratio of area of C/Ti in the target was 0.05. The photoelctrochemical property of the films improved when the ratio of area of C/Ti in the target was less than 0.10. When this ratio was 0.10 the photocurrent density of the film was 0.069 μA·cm-2 at 0 V under visible light illumination. However, an abnormal photoelectrochemical response was observed when the ratio of area of C/Ti in the target was 0.16.