Studies on Hydrophilicity Property of N-TiO2and Al/N-TiO2 Films Prepared by Magnetron Sputtering

TiO2具有光致亲水性能，即在紫外光照下，水滴与TiO2薄膜的接触角很快变为零。这一特性使TiO2具有自洁去污、防水雾等功能，具有广阔的应用前景，因而受到广泛关注。如何改善TiO2薄膜的亲水性能，使其具有可见光活性，并使亲水性保持较长的时间，成为近年来的研究热点。本研究的目的在于探索采用磁控溅射法制备N掺杂TiO2薄膜（N-TiO2）和Al、N双掺杂TiO2薄膜（Al/N-TiO2），改善TiO2的亲水性能。主要工作包括：（1）用TiN陶瓷靶，以O2、Ar为工作气体，采用射频反应磁控溅射法制备N-TiO2薄膜。用XRD、SEM、XPS、UV-Vis、CA（contactangle接触角）等分析...TiO2 involves a unique aspect of photo-induced hydrophilicity with a water contact angle of 0º. This phenomenon has been applied to various items, such as self-cleaning tites and anti-fogging mirror. Recent investigations have focussed on the improvement of hydrophilic property of TiO2 under visible light. The aim of this investigation is to explore N-TiO2 and Al/N-TiO2 films with excellent h...学位：工学硕士院系专业：化学化工学院材料科学与工程系_材料物理与化学学号：20043601

Hydrophilicity of TiO_2 Thin Films Codoped with Iron and Nitrogen

[中文文摘]采用溶胶-凝胶法制备了铁掺杂TiO2(Fe-TiO2)薄膜,将Fe-TiO2薄膜放置氨气气氛中高温处理,形成铁、氮共掺杂TiO2(Fe/N-TiO2)薄膜.通过XRD、XPS、SEM、UV-Vis法进行吸收光谱分析及薄膜表面亲水接触角分析,研究了铁、氮掺杂浓度,热处理温度,膜厚等因素对薄膜亲水性能的影响.结果表明,Fe/N-TiO2(0.5%Fe,摩尔百分数)显示出更佳的亲水性能,在可见光下优势尤为明显.铁掺杂主要作用是降低电子和空(的复合几率,氮掺杂可以增强TiO2薄膜在可见光区的吸收,两种效应相互结合,共同提高了薄膜在可见光下的亲水性能.[英文文摘]TiO2 doped with iron(Fe-TiO2)thin films were synthesized using sol-gel method.TiO2 codoped with iron and nitrogen(Fe/N-TiO2)thin films were prepared by calcining Fe-TiO2 thin films in ammonia atmosphere.The influence of iron and nitrogen doping concentration,heat-treatment temperature and film thickness on the hydrophilicity of the films were studied by XRD,XPS,SEM,UV-Vis spectra and measured water contact angle.The results indicated that Fe/N-TiO2(0.5%Fe,molar percent)films were optimum in hydrophilicity,especially under visible-light irradiation. Doping iron mostly reduced the recombination of electrons and holes, and doping nitrogen in TiO2 enhances photoresponse in visible-light region. The hydrophilicity benefited from both effects.国家自然科学基金(50472057

Preparation and Photocatalytic Activity of TiO_2 Powder Codoped with Iron and Nitrogen

Using TiCl4 as the titanium source, nanoparticles of TiO2 doped with nitrogen(N-TiO2) were synthesized by triethylamine. TiO2 powder codoped with iron and nitrogen(Fe/N-TiO2) were prepared by adsorption-deposition of Fe3+ on N-TiO2 and calcining at 400 ℃ for 2 h. From the XPS results for N1s binding energy at 399.6 eV and 396.6 eV, it is proposed that the partial N atoms as substitution atoms replace for O atoms in TiO2 lattice. The onset of the absorption spectrum of Fe/N-TiO2 has a 45 nm red-shift compared with that of TiO2. The results of photocatalytic degradation of methylene blue solution indicate that Fe/N-TiO2 (0.45% Fe3+) has a higher activity.Its photocatalytic activity is about 2 times as high as that of pure TiO2 under UV-light, and 3 times under sunlight. Doping of nitrogen in TiO2 enhances photoresponse in visible light region and doping of Fe3+ reduces the recombination of electrons and holes. Both of the above effects are beneficial for improving the performances of Fe/N-TiO2 photocatalyst.国家自然科学基金(No.50472057

Preparation and photocatalytic activity of TiO2 powder codoped with iron and nitrogen

Using TiCl4 as the titanium source, nanoparticles of TiO2 doped with nitrogen (N-TiO2) were synthesized by triethylamine. TiO2 powder codoped with iron and nitrogen (Fe/N-TiO2) were prepared by adsorption-deposition of Fe3+ on N-TiO2 and calcining at 400 degrees C for 2 h. From the XPS results for N1s binding energy at 399.6 eV and 396.6 eV, it is proposed that the partial N atoms as substitution atoms replace for O atoms in TiO2 lattice. The onset of the absorption spectrum of Fe/N-TiO2 has a 45 nm red-shift compared with that of TiO2. The results of photocatalytic degradation of methylene blue solution indicate that Fe/N-TiO2 (0.45% Fe3+) has a higher activity. Its photocatalytic activity is about 2 times as high as that of pure TiO2 under UV-light, and 3 times under sunlight. Doping of nitrogen in TiO2 enhances photoresponse in visible light region and doping of Fe3+ reduces the recombination of electrons and holes. Both of the above effects are beneficial for improving the performances of Fe/N-TiO2 photocatalyst

Hydrophilicity of TiO2 thin films codoped with iron and nitrogen

TiO2 doped with iron (Fe-TiO2) thin films were synthesized using sol-gel method. TiO2 codoped with iron and nitrogen (Fe/N-TiO2) thin films were prepared by calcining Fe-TiO2 thin films in ammonia atmosphere. The influence of iron and nitrogen doping concentration, heat-treatment temperature and film thickness on the hydrophilicity of the films were studied by XRD, XPS, SEM, UV-Vis spectra and measured water contact angle. The results indicated that Fe/N-TiO2 (0.5%Fe, molar percent) films were optimum in hydrophilicity, especially under visible-light irradiation. Doping iron mostly reduced the recombination of electrons and holes, and doping nitrogen in TiO2 enhances photoresponse in visible-light region. The hydrophilicity benefited from both effects

Government Spending,Liquidity Shocks and Real Business Cycle in China

改革开放以来中国经济周期表现出某些类似于国际经济的特征:居民消费、产出与Tb/gdP之间呈明显的逆向协动性;同时,也表现出某些不同于发达国家和新兴发展中国家的特征:居民消费波动的幅度大于产出波动,就业波动较为平滑。本文试图从开放经济的角度解释我国经济周期的特征事实。又鉴于我国政府在宏观经济调控中的重要影响,为此建立了一个考虑了外生的政府支出冲击与代表流动性冲击的偏好冲击的小国开放经济三部门rbC模型来给予解释,并考察了这些机制对经济周期的影响。本文发现:上述机制对宏观经济变量波动有重要的影响;这个模型能够解释92%以上的中国经济波动特征;该模型可以合理预测各变量与Tb/gdf之间的逆向协动性,可以合理预测各变量与产出之间的相关关系,说明中国的实际经济波动是可以在小国开放经济rbC模型框架内被合理解释的。Since initiation of the reform and opening - up policy,there are many facts same with international economy:consumption and output are negative correlated with TB/GDP,and there are many facts different form international economy;firstly,consumption's volatility is more than GDP output's;secondly,employment is much smoothing.This paper tries to explain the features of China's business cycle from the perspective of open economy.To do this,in respect of the omnipresence and omnipotence of China's government in macroeconomic management,it establishes a RBC model of three sections in small open economy that incorporates government consumption shocks and preference shocks representing liquidity shocks.It finds that these economic mechanisms have important impacts on real macroeconomic variables,this model can explain about 92%of the actual volatility,and can reasonably predict the negative correlations of TB/GDP with macroeconomic variables.It implies the business cycle in China can be explained well by the RBC in the small open economy.国家自然科学基金面上项目(71172004/G020102); 2011年度教育部哲学社会科学研究后期资助重点项目(11JHQ007

冰点下多孔介质中甲烷水合物的生成特性

冰点下水合物在多孔介质的生成是一个复杂的多相转化过程,为了研究冰点下多孔介质中水合物生成过程的水相转化率、气体消耗量与稳定压力等生成特性,在定容条件下,进行不同孔径与粒径的多孔介质中甲烷水合物在冰点下的生成实验。所使用的多孔介质平均孔径为12.95 nm、17.96 nm和33.20 nm。研究结果表明：水合物生成结束时水的转化率随着初始生成压力的增大而增大,随着温度的升高而降低,随着孔径的增大而增大;在相同的孔径下,多孔介质粒径的增大降低了水合物的生成速率但对最终气体消耗量没有影响;在相同的温度下,随着初始生成压力的增大,实验最终压力、气体消耗量与最终水的转化率均随之升高;温度越高,不同的生成初始生成压力下体系的最终稳定压力与水的转化率相差越大;在多孔介质的毛细管作用力与结合水的共同作用下,冰点下水合物生成的水的转化率会大大地降低。在本实验条件下,水相转化为水合物的比例最高为32.39%