非金属掺杂改性TiO₂光解水制氢气的研究

【作者】 卢新宁；

【导师】 张宁；

【作者基本信息】 南昌大学 ， 工业催化， 2006， 硕士

【摘要】 进入21世纪，能源和环境已成为人类可持续发展中面临的非常重要的两大课题，太阳能是可再生能源，能量巨大。氢气是一种理想的能源载体，氢气燃烧不会对环境造成污染。利用太阳能光催化分解水制氢是从长远角度解决人类能源问题和环境问题的一条重要途径。氧化钛是目前研究的最广泛的光催化材料，近几年来，为了提高氧化钛的光催化活性和其在可见光区的吸收性能，在降低氧化钛的带隙能方面开展了很多研究． 本文采用原位湿化学方法和化学沉积法合成了铂硫双掺杂的金红石相可见光TiO₂催化剂，对其形貌、结构、比表面积和紫外可见吸收光谱进行了表征。结果证明，铂硫双掺杂后的纳米氧化钛粉体的紫外一可见吸收光谱向可见光区移动，光解水制氢的催化性能的测试表明铂硫共掺杂的TiO₂催化剂性能要高于硫掺杂和铂掺杂的催化剂性能；用溶胶凝胶法制备了Si、CNTs共掺杂TiO₂，通过XRD表征表明600℃下焙烧是锐钛矿相。紫外可见吸收光谱表明Si掺杂的氧化钛向紫外光区移动，而CNTs掺杂稍微向可见光区移动。Si、CNTs共掺杂TiO₂在可见光下并不能分解水制得氢气。 适量的非金属与金属掺杂能够有效地抑制光生电子与空穴的复合，提高光催化反应活性。而过量掺杂则不能有效抑制、反而加速光生电子与空穴的复合，降低光催化反应活性。非金属掺杂改性的机理还不十分清楚，尚需深入阐述。 对于催化剂中金属或非金属掺杂的最佳量的确定，本文采用了最小二次乘法来解决，发现用它来处理掺杂量与其活性的关系，是非常有实用的价值。更多还原

【Abstract】 Energy and environment become the two important topics in the 21st century, Solar energy is enormous and reproducible. Hydrogen is ideal energy carrier, and the combustion of hydrogen is pollution-free for the environment. Photocatalytic decomposition water for hydrogen production is an advanced potential technique to convert solar energy into chemical energy and has many advantages in energy conversion and environment protection. At present, titanium dioxide is the most widely researched photocatalyst for various application, In recent years, In order to improve the photo reactivity of TiO₂ and to extend its light absorption into the visible region, several attempts have been made to lower the band-gap energy of n-TiO₂We synthesized （S,Pt）-codoped rutile TiO₂ photocatalyst by in situ hydrothermal method and chemical deposition method the absorption edge of （S, Pt）-codoped TiO₂ shifted to the longer wavelength region. The photocatalysts were analyzed by TEM observation、XRD、 BET and UV-Vis measurements, the result proved UV-Vis absorption spectra of the（S,Pt）-codoped rutile TiO₂ photocatalyst to be shifted to the longer wavelength region.the（S,Pt）-codoped had a better photocatalytic activity than S-doped and Pt-doped for Photocatalytic decomposition water for hydrogen production under visible light irradiation, Using the sol-gel method, the （Si, CNTs）-codoped TiO₂ was prepared, the catalyst was analyzed by XRD measurement that show anatase under calcined at 600℃. the UV-Vis absorption spectra provde Si-doped TiO₂ to be shifted to the shorter wavelength region. and CNTs-doped sightly shifted to the longer wavelength. the（Si, CNTs）codoped TiO₂ can not Photocatalytic decomposition water for hydrogen under visible light irradiation.Recombination of photo-excited electrons and holes is well hindered and photocatalytic activity is greatly enhanced by nonmetal and metal更多还原