闽南师范大学化学化工与环境学院,漳州 363000
NH3不仅是生产各种化学品的必要原料, 也是清洁能源的一种重要载体, 与人类社会的发展紧密联系。以清洁的太阳能作为唯一能量输入的光催化固氮技术, 在温和条件下利用N2和H2O直接产生NH3, 近年来引起人们广泛的关注。光催化固氮技术具有环境友好、节能、操作简便等优点, 但传统的半导体光催化剂在光捕获和光生载流子利用方面受到限制, 不能充分发挥其活性。因此, 需要设计相应的催化剂用来提高材料对惰性N2分子吸附和活化能力, 从而提高固氮性能。本文首先对光催化固氮进行了简要概述, 介绍了光催化固氮可能存在的两种反应机理, 随后着重介绍了含有氧、氮、硫空位的半导体材料对光催化固氮的影响。最后, 对光催化固氮领域的现有挑战和未来发展给出了一些实际的见解。
半导体 光催化 固氮 缺陷 氧空位 氮空位 催化机理 光生载流子 semiconductor photocatalytic nitrogen fixation defect oxygen vacancy nitrogen vacancy catalytic mechanism photogenerated carrier
Author Affiliations
Abstract
1 State Key Laboratory of Precision Spectroscopy, Department of Physics, and Department of Chemistry, East China Normal University, Shanghai 200062
2 Department of Physics and Electronics, Henan University, Kaifeng 475003
Dependence of surface-enhanced Raman scattering (SERS) from Calf thymus DNA on anions is investigated. With the silver colloid, the bands at 732, 960 and 1333 cm-1 for adenine (A), 1466 cm-1 for deoxyribose, and 1652 cm-1 for the C=O group of thymine (T) are observably enhanced. With the presence of the Cl- or SO^(2-)_(4) anions, the bands at 732 and 1326/1329 cm-1 for the symmetric stretching and skeletal vibrational modes of adenine (A) are dramatically enhanced, and the enhancement effect with the SO^(2-)_(4) ion is more than that with the Cl_ ion. The experimental results show that the DNA molecule can be adsorbed on the silver colloid particles through the C6N and N7 of adenine (A), the C=O of thymine (T) and deoxyribose. Moreover, the formed hydrogen bonding of the Cl_ or SO^(2-)_(4) ions to the C6NH2 group of adenine (A) can induce larger C6N electronegativity, which is favor for the C6N/N7 cooperative adsorption on the (Ag)^(+)_(n) colloid particles.
表面增强拉曼散射 阴离子影响 小牛胸腺DNA 氯离子 硫酸根离子 170.5660 Raman spectroscopy 300.6450 Spectroscopy, Raman 290.5860 Scattering, Raman 170.0170 Medical optics and biotechnology Chinese Optics Letters
2008, 6(7): 526
