聚氧化乙烯表面修饰对ZnO光学性质的影响

利用聚氧化乙烯(PEO)对ZnO表面进行修饰,研究有机包覆对ZnO光学性质的影响。用吸收光谱和光致发光光谱来表征和研究PEO包覆对ZnO纳米粒子光学性质的影响。吸收光谱结果表明随着ZnO薄膜中PEO含量的增加,激子吸收峰逐渐向低能侧方向移动。光致发光光谱是由紫外发射和与氧空位有关的深能级缺陷发光组成,且随着ZnO薄膜中PEO含量的增加,紫外发射与深能级发光强度之比逐渐增大,当ZnO薄膜中的PEO达到最大值时,其比值为31．5,远远大于纯ZnO薄膜的紫外发射与深能级发光强度之比1．04。由此可见,ZnO被PEO包覆后,提高了紫外发光效率,改善了ZnO薄膜的质量。     

纳米介孔ZrO2及其表面修饰的发光性质

水热合成法制备的高度有序多孔ZrO2具有规则六角排列、均匀纳米孔洞(约1．8nm)，并且其蓝、(近)紫外光发射强度比纳米微晶材料高2个数量级。本文研究了纳米介孔ZrO2这种不同于常规体材料与纳米晶材料的特殊发光性质。通过化学方法对纳米介孔ZrO2进行表面修饰后，能进一步提高其光发射聋度约3倍。通过这些发光性质的研究，以期增进对ZrO2发光机理的认识。     

Synthesis and Characterization of Surface-modified Rutile Nanoparticles And Transparent Polymer Composites Thereof

Nanoparticles of rutile, a crystal modification of titanium dioxide, were synthesized in strongly acidic solutions by hydrolysis of titanium tetrachloride. The particles of average diameter 2nm were coated in situ with a layer of dodecylbenzenesulfonic acid (DBSA) and isolated as a powder. Remarkably, dispersions of this powder in toluene were essentially transparent at the visible wavelengths but absorbed UV radiation over a broad wavelength range. The DBSA-coated rutile was also embedded in poly(styrene) and a poly(carbonate), resulting in polymer nanocomposites acting as visually transparent UV filters.     

Second-order Nonlinearities of CdS Nanoparticles Studied by Hyper-Rayleigh Scattering Technique

Optical nonlinearities of semiconductor nanoparticles are of great interest recently. So fartheir third-order nonlinear optical (NLO) properties have been widely studied. However,there are only few studies on second-order NLO properties, because it is believed that thecentrosymmetry or near-centrosymmetry of spherical nanoparticles eliminate their firstorder hyperpolarizability 6 values to'zero or near zero. And for a long time it remains aproblem to directly study the second-order=NLO pro…     

Chemical modification and the photoluminescence stabilization of titanic acid nanotubes

1 Introduction In 1998, Kasuga et al. obtained a new kind of nanotubular materials by treating anatase TiO2 power with concentrated NaOH aqueous solution[1,2]. This work soon aroused general concern due to their exten- sive applications in the photoelectr…     

TiO_2纳米粒子的表面修饰研究

利用表面修饰法合成了油酸 (OA)修饰的TiO2 纳米粒子 ,采用红外光谱 (IR)、透射电子显微镜 (TEM)和X射线光电子能谱 (XPS)对表面修饰的TiO2 纳米粒子进行了结构表征 ,并研究了油酸浓度对TiO2 表面覆盖量及在油中分散性能的影响 .研究结果表明通过油酸表面修饰 ,成功合成了具有油分散性能的纳米TiO2 ,并且获得了油酸修饰量与TiO2 的最佳配比 .