C60-聚甲基丙烯酸甲脂复合膜的结构、光学和电荷转移特性

描述了通过溶胶-凝胶法制备的C60-PMMA复合膜的结构、紫外-可见吸收特性、Raman散射特性和红外吸收特性.通过对C60紫外-可见吸收光谱,Raman散射谱和红外吸收谱的实验和理论分析,研究了C60与PMMA之间的电荷转移.     

溶胶-凝胶制备ZnO-SiO2复合膜的量子效应和上转换发光

采用溶胶-凝胶技术在玻璃衬底上制备了ZnO薄膜和ZnO-SiO₂复合膜.原子力显微镜照片显示ZnO薄膜具有球状纳米晶粒;可见光-紫外透射光谱表明ZnO-SiO₂复合膜在可见光区的透过率大约是85%,透过率从330 nm开始下降,到290 nm附近降为零.由于量子效应,吸收边出现明显的蓝移.在室温下用不同波长的光激发ZnO-SiO₂复合膜,光致发光谱显示ZnO-SiO₂复合膜对应于激子发射的290 nm附近的紫外发光峰与透射谱所显示的吸收边位置一致,没有出现斯托克斯红移.同时,ZnO-SiO₂复合膜出现了双光子和三光子吸收现象和上转换发光现象. 关键词： 2')" href="#">ZnO-SiO₂ 量子效应 双光子和三光子吸收 上转换发光     

掺杂C60的SiO2气凝胶的制备及荧光特性研究

利用“化学掺杂”方法，制备掺杂C₆₀-SiO₂气凝胶，对掺杂C₆₀-SiO₂气凝胶的红外吸收光谱、飞行时间质谱的测试表明C₆₀分子被成功地掺入SiO₂气凝胶中．室温条件下，在Ar⁺激光（488nm）激发下，观察到掺杂C₆₀-SiO₂气凝胶有很强的可见发光现象，发光峰位较纯C₆₀发光明显蓝移 关键词：     

纳米ZnO和ZnO-SiO2复合薄膜的光学性质研究

通过溶胶凝胶(sol-gel)法分别在玻璃衬底上制备了ZnO纳米薄膜和ZnO-SiO₂纳米复合薄膜,并利用紫外-可见光分光光度计对薄膜的光学性能进行了分析.可见光-紫外透射谱显示,随着ZnO溶胶浓度从0.7mol/L降低到0.006mol/L,制备的ZnO薄膜从只出现一个380nm(对应的光学禁带宽度为3.27eV)左右的吸收边到在380和320nm(对应的光学禁带宽度为3.76eV)左右各出现一个吸收边,并且随着ZnO溶胶浓度的降低,在380—320nm波段内的透过率明显提高.而Z 关键词： 纳米ZnO 2复合薄膜')" href="#">ZnO-SiO₂复合薄膜 溶胶凝胶法 透射率     

细胞色素C包裹在溶胶-凝胶中的构象变化

利用溶胶--凝胶(Sol-Gel)法制备了包埋生物分子细胞色素c的生物无机杂化材料. 利用紫外可见吸收谱和同步辐射小角散射对其进行了表征. 通过细胞色素c吸收谱Soret band的位移, 得出基质包埋细胞色素c的界面效应对细胞色素c构象变化的影响. 利用同步辐射小角散射, 计算细胞色素c在凝胶样品中的尺度分布, 平均回转半径, 质量分形维数. 对小角散射研究结果和紫外可见吸收谱测试结果进行了比较和详细讨论.     

溶胶-凝胶ZrO2-TiO2高折射率光学膜层的抗激光损伤性能研究

采用溶胶-凝胶方法制备了ZrO₂-TiO₂(Ti含量为0—100mol%)高折射率光学薄膜. 借助激光动态光散射技术研究溶胶微结构. 采用傅里叶变换红外光谱、原子力显微镜、薄膜光学常数分析仪、漫反射吸收光谱及强激光辐照实验，对膜层的结构、光学性能及抗激光损伤性能进行了系统表征. 结果显示，溶胶-凝胶工艺可以在部分牺牲折射率的情况下，使膜层的抗激光损伤性能得到大幅度提升. 随Ti含量从0mol%增加至100mol%，膜层的平均损伤阈值呈下降趋势，当Ti含量从0mol%增加至60mol%时，平均损伤阈值从57.1J/cm²下降到21.1J/cm²(辐照激光波长为1053nm，脉冲宽度为10ns，“R/1”测试模式)，当Ti含量从60mol%增加至100mol%时，平均损伤阈值变化很小. 综合溶胶微结构、膜层光学性能和损伤实验结果可以推断，强激光诱导多光子吸收是引起膜层损伤的主要原因. 不同配比的复合膜之间光学带隙的显著差异导致相同辐照激光情况下多光子吸收的概率发生变化，从而导致损伤阈值的规律性变化. 关键词： 2-TiO₂薄膜')" href="#">ZrO₂-TiO₂薄膜 溶胶-凝胶 激光诱导损伤 光学带隙     

溶胶凝胶制备氧化钒薄膜的生长机理及光电特性

采用溶胶凝胶法, 在不同的退火温度下制备了不同的氧化钒薄膜. 利用扫描电子显微镜、X射线衍射仪、高阻仪、紫外-可见分光光度计和傅里叶红外光谱仪等, 对薄膜的形貌、晶态、电学和光学特性进行了分析. 结果表明, 溶胶凝胶法获取V₂O₅薄膜的最佳退火温度为430 ℃, 低于此温度不利于使有机溶剂充分分解, 高于此温度则V–O键发生裂解、形成更多的低价态氧化钒. 本文制备的氧化钒薄膜具有较高的电阻温度系数和光吸收率, 适合应用在非制冷红外探测器中. 本文揭示了溶胶凝胶法制备氧化钒薄膜的生长机理. 关键词： 氧化钒薄膜 溶胶凝胶 光电特性 生长机理     

团簇红外吸收谱的理论研究

根据时间关联函数理论，可以结合分子动力学模拟而计算团簇的红外吸收谱. 应用正交紧束缚分子动力学模拟，计算了C₆₀的红外吸收谱. 结果与实验相符，足以识别团簇 体系的红外吸收谱. 这将是研究纳米团簇体系的有力理论分析工具. 关键词： 红外吸收谱 团簇 时间关联函数     

溶胶-凝胶方法制备ZrO2及聚合物掺杂ZrO2单层光学增反射膜

以丙醇锆(Zr(OPr)₄)为原料，乙酸(HAc)为络合剂，聚乙二醇(PEG200)和聚乙烯吡咯烷酮(PVP)为大分子添加剂，在乙醇体系中成功合成了ZrO₂及聚合物掺杂ZrO₂溶胶.用旋涂法在K9玻璃基片上制备单层光学增反射膜.借助小角X射线散射和激光动态光散射技术研究胶体的微结构.采用傅里叶变换红外光谱、差示扫描量热分析、X射线衍射分析、原子力显微镜、紫外/可见/近红外透射光谱以及椭偏仪对薄膜的结构和光学性能进行表征.用输出波长为1064 关键词： 二氧化锆 溶胶-凝胶 增反射膜 激光损伤     

基于电子顺磁共振的锌卟啉敏化TiO2光催化性机理的研究

为了研究锌卟啉/TiO₂复合光催化剂的光催化效率及电子转移问题, 本文采用溶胶凝胶法制备了锌卟啉/TiO₂的混合光催化材料, 并利用紫外可见光谱、电子顺磁共振谱对锌卟啉/TiO₂复合光催化剂进行了表征与分析. 采用溶胶凝胶法制备了锌卟啉-TiO₂的混合光催化材料, 通过比较纯P25型TiO₂和掺入质量比分别为0.2%, 0.5%, 0.9%锌卟啉敏化剂的锌卟啉/TiO₂混合光催化材料的紫外可见光谱图可知, 加入适量锌卟啉敏化剂可提高TiO₂对甲基橙溶液的降解效率, 过多的掺入锌卟啉敏化剂会导致TiO₂表面被敏化剂覆盖, 从而影响了其对光子的吸收, 降低TiO₂的光催化效率, 降低TiO₂的光降解率, 甚至低于纯TiO₂的光降解率. 应用电子顺磁共振技术对锌卟啉敏化TiO₂光催化剂的光催化机理进行了合理的解释, 当使用紫外可见光源对粉末样品进行辐照时, 锌卟啉受光辐照产生的激发态电子促进具有强氧化性的Ti³⁺和超氧根自由基的生成, 从而有效的促进了光生空穴-电子对的分离, 提高了TiO₂的光催化性能.     

Structural modification of C60 films induced by 300-keV Xe-ion irradiation

The structural modification of C 60 films induced by 300-keV Xe-ion irradiation was investigated.The irradiated C 60 films were analysed using Fourier transform infrared spectroscopy,the Raman scattering technique,ultraviolet/visible spectrophotometry and atomic force microscopy.The analysis results indicate that the Xe-ion irradiation induces polymerization and damage of the C 60 molecule and significantly modifies the surface morphology and the optical property of the C 60 films.The damage cross-section for the C 60 molecule was also evaluated.     

Analysis of spectral features of the optical constants of fullerene and halogen-fullerene films near the absorption edge

This paper reports on measurements of IR spectra and of the extinction coefficient in the 1.2-to 4.2-eV range made on C₆₀Br_x films and compared with those for pure C₆₀ films. The modification of the electronic spectrum near the absorption edge is connected with differences in the film structure and with suppression of charge-transfer excitons. The C₆₀Br_x films exhibit additional absorption below the fundamental absorption edge of C₆₀.     

Optical properties of endohedral Li@C60

UV–VIS, IR and Raman investigations have been carried out on purified Li@C₆₀ produced by low energy ion implantation of C₆₀. Two endohedral fractions can be isolated that have very different optical properties and stabilities. Here we show that the first endohedral fraction is a dimer species and the second fraction is the monomer. The IR spectra of sublimed monomer films show a prominent peak at around 1.1 μm corresponding to the first electronic transition of the C₆₀⁻ anion. Raman spectra show the vibrational–rotational movement of the Li inside the carbon cage.     

镶嵌在SiO2薄膜中InAs纳米颗粒的Raman散射

对镶嵌在SiO₂薄膜中纳米InAs颗粒的Raman散射谱进行了研究.与大块InAs晶体相比,InAs纳米颗粒的Raman散射谱具有相似的特征,即由纵光学声子模和横光学声子模组成,但是散射峰宽化并红移.用声子限域效应解释了散射峰的红移现象,并结合InAs纳米颗粒的应力效应解释了红移量与理论值的差异. 关键词： 2薄膜')" href="#">SiO₂薄膜 InAs量子点 Raman散射     

Optical and electrical properties of C60Tex films

The structure, composition, and electrical and optical properties of thin tellurium-intercalated fullerene films C₆₀Te_x are investigated. The samples of compositions from C₆₀Te_0.1 to C₆₀Te₆ are prepared by thermal evaporation. The sample composition and the impurity distribution are controlled by the Rutherford backscattering technique. The Raman vibrational spectra indicate changes in the symmetry of a C₆₀ molecule: the strain of the molecule increases with a decrease in the tellurium concentration and decreases as the tellurium impurity concentration increases. The evolution of the optical absorption spectra and the electrical conductivity suggests that intercalation of a tellurium impurity leads to modification of the electronic structure of the material. This process is accompanied by a shift and change in shape of the optical absorption edge and a change in the electrical conductivity of films by several orders of magnitude depending on the composition. The electrical conductivity is minimum at a low tellurium impurity content.     

紫外激光和压力共同作用下C60-peapod的聚合相变研究

采用气相扩散方法将C₆₀分子填充到单壁碳纳米管(SWNTs)中，制备出高填充比率的豆荚形纳米材料C₆₀@SWNT，又称为peapod.用金刚石对顶砧(DAC)装置获得高压，在高压下同时利用紫外激光处理样品，通过激光和压力的共同作用研究了C₆₀分子在碳管内的聚合相变.在21.5GPa高压下，同时紫外激光(325nm)照射30min后，拉曼光谱表明C₆₀分子在碳管内发生了聚合，形成一维链状O相聚合结构，且该相变是不可逆的. 关键词： 60 peapod')" href="#">C₆₀ peapod 紫外激光 高压 拉曼光谱     

Vibrational and optical properties of a one‐dimensional organic–inorganic crystal [C6H14N]PbI3

Self‐assembled organic–inorganic [C₆H₁₄N]PbI₃ crystals were synthesized. The crystal structure consists of one‐dimensional semiconductor chains formed by infinite PbI₆ face‐sharing octahedra aligned along the a‐axis. The organic cations are linked to the inorganic chains by N H· · ·I hydrogen bonds and act as insulator barriers. The vibrational properties of [C₆H₁₄N]PbI₃ were studied using polarized Raman scattering and infrared (IR) absorption. The observed Raman and IR spectral features were identified by comparison with the vibrational properties of homologous compounds and with the vibrational wavenumbers calculated using the ab initio PM3 method. Moreover, the photoluminescence and diffuse reflectance of [C₆H₁₄N]PbI₃ single crystals, along with the UV‐Vis absorption of spin‐ coated films, were measured. A strong green‐blue luminescence due to radiative recombinations of 1D excitons is observed. The Stokes shift is estimated at 70 meV. Copyright © 2008 John Wiley & Sons, Ltd.     

Vibrational spectroscopy and DFT calculations of N,N′‐dicyclohexylcarbodiimide

Infrared (IR) and Raman spectra were obtained for N,N′‐dicyclohexylcarbodiimide (DCC) in the solid state and in CHCl₃ solution. Structures and vibrational spectra of isolated, gas‐phase DCC molecules with C₂ and C_i symmetries, computed at the B3‐LYP/cc‐pVTZ level, show that the IR and Raman spectra provide convincing evidence for a C₂ structure in both the solid state and in CHCl₃ solution. Using a scaled quantum‐chemical force field, these density functional theory calculations have provided detailed assignments of the observed IR and Raman bands in terms of potential energy distributions. Comparison of solid‐state and solution spectra, together with a Raman study of the melting behaviour of DCC, revealed that no solid‐state effects were evident in the spectra. Copyright © 2010 John Wiley & Sons, Ltd.     

Nucleation of diamond on silicon wafers using C60 in the hot filament chemical vapour deposition system

Scanning electron microscopy and Raman shifts were used to study the process of diamond nucleation and growth using C60 in the hot filament chemical vapour deposition (HFCVD) system.The process of nucleation and growth of diamond films on silicon wafer using C60 as intermediate layer in HFCVD system is described.In order to increase the density of diamond nuclei on the wafers,it is not necessary to use negative bias.The UV-light pre-treatment is not beneficial for improving the diamond nucleation.The multi-layers of C60 molecules,but not a monolayer,can increase the density of diamond nuclei in the presence of H atoms.     

织构C60薄膜的生长与光致发光特性

用Hot Wal方法，在氟金云母单晶上生长出了（111）织构的C₆₀薄膜．用X射线衍射、Raman散射、扫描电子显微镜和原子力显微镜研究了织构C₆₀薄膜的结晶质量和结构特性．测量了织构C₆₀薄膜在室温300K和低温77K的光致发光光谱．对所得结果进行了分析与讨论 关键词：