摘要
在不同的氧气与氮气流量比条件下,利用射频磁控溅射技术在载玻片衬底上成功沉积了TiO2-xNx薄膜。采用亚甲基蓝染料为光降解污染物,考察了薄膜的光催化活性;检测了薄膜的XRD谱和透射光谱;并利用基于密度泛函理论的第一性原理计算了N掺杂锐钛矿相TiO2的能带结构及其在费米能级附近的电子态密度。结果表明,在氧气流量50sccm、氮气流量0.5sccm条件下沉积的TiO2-xNx薄膜的光催化活性最高;与纯TiO2样品相比,N掺杂TiO2样品的晶体结构没有发生改变,吸收边红移;N掺杂使TiO2的禁带宽度减小,电子态密度向低能量方向移动,从而使其光响应范围扩展,光催化活性增强。
TiO2-Nx thin films were successfully deposited onto microscope glass slides by RF sputtering technology with different flow ratio of oxygen to nitrogen. Photocatalytic activity of the obtained thin films was evaluated by photodegradation tests of methylene blue. XRD patterns and transmission spectra of the films were determined. The energy band structure and density of electronic states （DOS） near Fermi level of N-doped anatase TiO2 were calculated using the first principle based on density functional theory （DFT）. The results indicate that the TiO2-xNx thin film prepared with 50 sccm O2 flow rate and 0.5 sccm N2 flow rate has the highest photocatalytic activity. Compared with pure TiO2, N-doped TiO2 has no change in crystal structure, but its absorption edge shows red shift. N doping makes the band gap of TiO2 decreased and DOS movement towards the low-energy side, resulting in light response region extended and photocatalytic activity enhanced.
出处
《稀有金属与硬质合金》
CAS
CSCD
北大核心
2013年第1期45-49,共5页
Rare Metals and Cemented Carbides
基金
河北大学自然科学研究计划基金资助项目(2007-110)
关键词
TiO2-xNx薄膜
光催化活性
能带结构
电子态密度
第一性原理
TiO2-xNx thin film
photocatalytic activity
energy band structure
density of electronic states
the first principle
