掺氮二氧化钛薄膜的常压化学气相沉积及其结构性能研究

用常压化学气相沉积（APCVD）法，以四氯化钛（TiCl4）、氧气（O2）和氨气（NH3）作为气相反应先驱体，成功制备了掺氮二氧化钛（TiO2）薄膜。XRD、XPS和UV—Vis透射光谱研究表明，氮掺杂在二氧化钛薄膜中引入Ti4O7相，抑制了锐钛矿相向金红石相的转变；氮掺杂促使光吸收限红移，提高了薄膜在可见光照射下的光催化效率，并改善了薄膜表面的亲水性能。该工艺成本低廉，成膜速度快（150nm／min），适用于工业化浮法玻璃生产线，产业化前景广阔。     

N,Fe共掺杂TiO_2纳米材料的固相合成及其对喹啉的可见光降解

采用固相反应法分别合成了铁掺杂二氧化钛(Fe-TiO2)及氮和铁共掺杂二氧化钛(N-Fe-TiO2)纳米材料.并对材料进行了XRD、SEM、UV-Vis、XPS、AAS及全自动元素分析等技术的物相织构及元素组成表征,同时研究了催化剂对喹啉的可见光降解性能.结果表明,在球形的N-Fe-TiO2纳米材料中,N以阴离子(N3-)进入二氧化钛晶格,Fe3+以同晶取代方式占据TiO2晶格中Ti的位置,紫外-可见漫反射吸收光谱红移到600nm.N/Fe投料比的增大有助于N-Fe-TiO2催化剂晶型的转化.在25℃、pH=6.5下,所制得的光催化材料对喹啉的可见光降解行为均具有较高的光催化活性,并服从一级反应动力学规律,而纯TiO2对喹啉不降解.N-Fe-TiO2(n(N2H4.H2O):n(FeCl3.6H2O)=1:9)催化剂对喹啉的可见光降解速率常数比Fe-TiO2大.     

退火对Cr3+离子掺杂Al2O3薄膜的结构及发光性能影响

用脉冲激光沉积技术在Si(100)基底上制备了纯Al2O3、掺杂浓度为0.3%、1%(质量分数)的Cr3+∶Al2O3薄膜。制备态的薄膜为立方γ-Al2O3结构,经800℃真空条件下退火1h样品的结晶度有所提高,呈现α-Al2O3相与γ-Al2O3相的衍射峰。薄膜基本保持了靶材中原有各元素成分比例,平均粒径为250nm,形貌为条形。与Al2O3粉体相比,制备态薄膜在386nm处的发光峰强度明显提高。这可归因于薄膜中氧空位的增加使双氧空位吸收电子所产生的F2+色心浓度提高。薄膜经真空退火后在332、398nm附近的发光峰强度明显增强,这是由于薄膜中氧空位的增加提高了F+、F色心浓度。与此同时,制备态薄膜在386nm附近发光峰经退火后由386nm蓝移至381nm,可归因于退火后制备态薄膜的内应力得到了释放。1%(质量分数)Cr3+掺杂薄膜在646、694nm出现Cr3+离子由4 T2能级跃迁至4 A2能级及由E-能级跃迁至4 A2能级产生的荧光发光峰。     

掺氮二氧化钛薄膜的介质阻挡放电化学气相沉积及其结构性能研究

采用介质阻挡放电化学气相沉积（DBD-CVD）法,以四异丙醇钛（TTIP）作为钛源,氨气（NH3）和笑气（N2O）分别作为氮源的气相反应先驱体,成功制备了不同掺杂量的掺氮二氧化钛（TiO2）薄膜。SEM、XRD、XPS和UV-Vis透射光谱研究表明：所制得的掺氮二氧化钛薄膜均为锐钛矿相,氮源的引入对TiO2薄膜晶粒成长、晶体取向、表面形貌影响很大,并促使光吸收限红移,提高了薄膜在可见光照射下的光催化效率,并改善了薄膜表面的亲水性能。且NH3掺氮效果整体好于N2O。     

阴极恒电流法制备SmS光学薄膜

以SmCl3·6H2O和Na2S2O3·5H2O为原料,采用电沉积法在单晶硅(100)和玻璃基板制备了SmS光学薄膜.采用XRD、AFM和紫外可见光分光光度计对薄膜进行了表征.研究了[Sm3 ]/[S2O32-]、溶液的pH值对于薄膜的物相的影响.结果表明:在[Sm3 ]/[S2O32-]=1:2,控制溶液pH值为4.50以及沉积1h的条件下,可制备出70nm厚单一晶相且表面比较平整的SmS薄膜,薄膜具有(331)方向的取向性.紫外光谱测试表明所制备的SmS薄膜具有290～300nm的紫外吸收特性,薄膜的禁带宽度约为3.6eV.     

氮掺杂TiO_2的制备及其光催化性能研究

应用溶胶-凝胶法,以尿素和钛酸丁酯为原料制备前躯体,前躯体在500℃、焙烧3 h条件下制备不同浓度掺杂氮的TiO2纳米粉体。采用X射线衍射(XRD)、扫描电镜(SEM)、能谱分析(EDS)、紫外可见光谱(UV-Vis)等分析手段对样品的物相、形貌、成分和吸光性能进行表征,并且以亚甲基蓝溶液为模拟污染物在阳光下进行光催化实验。结果表明:样品主要为锐钛矿相二氧化钛及少量的金红石型二氧化钛,颗粒粒径小于300 nm,有一定程度的团聚,样品中含有质量分数分别为0、2.99%、6.23%、11.38%的氮元素,氮掺杂样品的光谱吸收边缘红移至400~470 nm。光催化实验表明:氮掺杂可以大大改善TiO2在可见光波段的光催化性能。     

氮流量对TaN薄膜微结构及性能的影响

采用反应直流磁控溅射法在Al2O3陶瓷基片上制备TaN薄膜,研究了氮流量(N2/(N2+Ar))对TaN薄膜微结构及性能的影响。结果表明,随氮流量的增大,TaN薄膜的氮含量、电阻率、方阻以及TCR的绝对值逐渐增大,而沉积速率逐渐降低。当N2流量较低(2%～4%)时,TaN薄膜中主要含有电阻率和TCR绝对值较低的六方Ta2N相(hcp),薄膜的电阻率在344μΩ.cm到412μΩ.cm范围内,薄膜的TCR绝对值约为几十ppm/℃。当氮气流量较高(5%～6%)时,薄膜中Ta2N相消失,薄膜中主要含有TCR绝对值较大的体心四方结构(bct)的TaN和四方结构(bct)的Ta3N5相,薄膜的电阻率在940μΩ.cm到1030μΩ.cm范围内,薄膜的TCR绝对值约为几百ppm/℃。     

多弧离子镀镀制掺氮二氧化钛薄膜及其光吸收特性的研究

利用多弧离子镀在玻璃衬底上制备了TiO2薄膜和氮掺杂的TiO2薄膜样品，并对样品进行了220～500℃温度的热处理，通过X射线衍射（XRD）以及UV—Vis分光光度计等测试手段对热处理前后的样品的结构、光吸收特性进行了分析。结果表明：制备出的薄膜为非晶态结构，热处理后向锐钛矿、金红石相转变。理想工艺下镀制的掺氮TiO2薄膜经400℃热后，TiO2薄膜的光吸收限可由385nm红移至500nm。     

新型光致发光纳米薄膜的研制

阐述了利用喷雾热解技术在硅片衬底上生长锰掺杂铝酸锌光致发光纳米薄膜的方法.该纳米薄膜制备方法简单、经济和环保.通过XRD分析测试结果表明,当三氯化铝在氢氧化锌中的含量高于20%,衬底温度高于100℃时,在衬底上会形成ZnAl2O4-ZnO纳米复合薄膜;该复合薄膜经0.1mol/L盐酸处理后,形成ZnAl2O4尖晶石矿纳米薄膜.研究了金属锰离子掺杂ZnAl2O4纳米薄膜的光致发光性能,荧光光谱实验结果表明,这种利用喷雾热解技术生长的掺锰ZnAl2O4尖晶石纳米薄膜,在525nm附近有一发光带,为Mn2 的4T1(4G)6A1(6S)跃迁.     

微波-ECR等离子体辅助沉积Zr-N薄膜结构和性能研究

在不同氮流量下,利用微波-ECR等离子体溅射沉积技术在45#钢基体上制备了ZrN薄膜.XRD、TEM分析结果表明:随着充入N2流量的改变,薄膜结构由单一的ZrN结构向ZrN和ZrNx复合结构转变,然后出现非晶态结构.当N2流量在(2～8) sccm之间,薄膜为ZrN结构;在(10～12) sccm时,为ZrN和正交的ZrNx(a=0.3585 nm,b=0.4443 nm,c=0.5798 nm)混合型结构;14 sccm时出现非晶化趋势.俄歇电子谱仪(AES)和探针分析表明:薄膜中氮含量为7.73%～66.96%.同时对薄膜的硬度进行了测试,薄膜硬度在19.82 GPa～26.32 GPa之间,随氮值的变化,先增加后降低.对硬度最高的4#样品进行了摩擦性能测试,磨损率约4.5×10-8 mg/min.薄膜这些性能的变化是由于不同氮流量下薄膜结构发生变化造成的.     

超声波辅助扩孔对氧化铝模板结构的影响

在0.3mol/dm3的草酸溶液中,采用二次阳极氧化法制备多孔氧化铝模板,研究了阳极氧化后的扩孔处理对多孔膜形貌和结构的影响.SEM和FE-SEM结果表明,经20min超声波扩孔处理后,多孔氧化铝模板纳米孔的结构更加趋于规则,表观孔径从30nm增大到70nm,其扩孔效果较常规扩孔方法更为明显.超声波扩孔时间增加到40min后,多孔膜孔径扩大至100nm,但某些区域的纳米孔壁已被部分溶解.在一定的电压范围内,随着电压增加,经超声波扩孔后的多孔氧化铝膜孔径增大,有序度有较大提高.     

Photocatalytic activity of pulsed laser deposited TiO2 thin films in N2, O2 and CH4

We report on pulsed laser deposition of TiO₂ films on glass substrates in oxygen, methane, nitrogen and mixture of oxygen and nitrogen atmosphere. The nitrogen incorporation into TiO₂ lattice was successfully achieved, as demonstrated by optical absorption and XPS measurements. The absorption edge of the N-doped TiO₂ films was red-shifted up to ∼ 480 nm from 360 nm in case of undoped ones.The photocatalytic activity of TiO₂ films was investigated during toxic Cr(VI) ions photoreduction to Cr(III) state in aqueous media under irradiation with visible and UV light. Under visible light irradiation, TiO₂ films deposited in nitrogen atmosphere showed the highest photocatalytic activity, whereas by UV light exposure the best results were obtained for the TiO₂ structures deposited in pure methane and oxygen atmosphere.     

硅衬底Al2O3∶Tb3+薄膜的制备及其发光性能

采用溶胶凝胶法在硅衬底上制备了Al₂O₃∶Tb³⁺薄膜; 并采用DTA-TG、XRD、SEM、AFM及光致发光光谱对其进行了一系列表征; 分析了Al₂O₃∶Tb³⁺薄膜的发光机理, 探讨了热处理温度和Tb³⁺掺杂浓度对发光性能的影响规律. 研究结果表明, 采用溶胶凝胶法制备工艺, 制备了高发光强度的Al₂O₃∶Tb³⁺薄膜, 薄膜的最佳激发波长为240nm, Tb³⁺的最佳掺杂浓度为5mol%(Tb₂O₃/Al₂O₃=5mol%), 在240nm光激发下, 最强的发射峰出现在544nm附近; 并且制备的Al₂O₃∶Tb³⁺薄膜表面致密、平整且无裂纹产生, 表面粗糙度约为1.3nm, 有利于硅基光电子器件的制备和应用.     

Preparation and photocatalytic activity of N-doped TiO2 nanotube array films

The N-doped TiO₂ nanotube array films were fabricated directly by one-step electrochemical anodic oxidation of Ti foils in an HF electrolyte containing ammonium and nitrate ions. The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectrometer (EDX), and ultraviolet–visible (UV–vis) absorption spectroscopy, respectively. The photocatalytic activities were evaluated by the degradation of methyl orange (MO) under visible light irradiation. The results showed that N dopant was successfully introduced into the TiO₂ nanotube array films. The N-doped TiO₂ nanotube array films showed a red shift and an enhancement of the absorption in the visible light region compared to the undoped sample. The photocatalytic activities of the N-doped TiO₂ samples were much higher than those of the undoped sample. A maximum enhancement of photocatalytic activity was achieved for the N-doped TiO₂ sample prepared in 0.07 M HF electrolyte containing 1.0 M NH₄NO₃, and 81% of MO was degraded in 150 min under visible light irradiation.     

Room temperature one-step synthesis of microarrays of N-doped flower-like anatase TiO2 composed of well-defined multilayer nanoflakes by Ti anodization

Microarrays of N-doped flower-like TiO(2) composed of well-defined multilayer nanoflakes were synthesized at room temperature by electrochemical anodization of Ti in NH(4)F aqueous solution. The TiO(2) flowers were of good anatase crystallinity. The effects of anodizing time, applied voltage and NH(4)F concentration on the flower-like morphology were systematically examined. It was found that the morphologies of the anodized Ti were related to the anodizing time and NH(4)F concentration. The size and density of the TiO(2) flowers could be tuned by changing the applied voltage. The obtained N-doped flower-like TiO(2) microarrays exhibited intense absorption in wavelengths ranging from 320 to 800 nm. Under both UV and visible light irradiation, the photocatalytic activity of the N-doped flower-like TiO(2) microarrays in the oxidation of methyl orange showed a significant increase compared with that of commercial P25 TiO(2) film.     

Synthesis and characterization of the N-doped TiO2 photocatalyst for the photodegradation of methylene blue and phenol

To extend the light absorption of TiO2-based photocatalysts towards the visible-light range and to eliminate the rapid recombination of excited electrons/holes during photoreaction, a new type of photocatalyst (N-doped TiO2) powder was prepared through a simple sol-gel process. The crystal phase composition, structure, and light absorption of the new photocatalyst were comprehensively examined via X-ray diffraction, ultraviolet-visible (UV-Vis) absorption spectroscopy, and atomic-absorption spectroscopy. The photo-oxidation efficiency of the photocatalyst was also evaluated in the photodegradation of methylene blue (MB) and of phenol in aqueous solutions under visible-light irradiation from a neon lamp (lambda > 400 nm). The results of the analyses that were performed in this study indicated that the N-doped TiO2 could eliminate the electron/holes recombination and could increase the light absorption in the visible range. The results of the analysis of the UV-Vis diffuse reflection and optical-absorption spectra indicated that a new energy level below 3.2 eV generated in the N-doped TiO2 promoted the optical absorption in the visible-light region and made visible-light excitation possible (E < 3.2 eV). The experiment demonstrated that the photo-oxidation efficiency of MB when N-doped TiO2 powder was used was significantly higher than that when the conventional TiO2 powders were used. The development of such photocatalyst may be considered a breakthrough in the large-scale utilization of solar energy to address the current and future environmental needs.     

Photoelectrochemical and optical properties of N-doped TiO2 thin films prepared by oxidation of sputtered TiNx films

Nitrogen-doped titanium dioxide thin films with visible light photoresponse were prepared by oxidation of sputtered TiN_x films, whose nitrogen contents can be easily changed by controlling the volume ratio of N₂/(Ar + N₂) during reactive direct current (DC) magnetron sputtering process. The reference TiO₂ sample was also deposited by the same method under Ar/O₂ gas mixture. The as-prepared films were characterized by X-ray diffraction, scanning electron microscopy, X-ray photoemission spectroscopy, UV-vis spectrophotometry and photoelecrochemical measurements. The formation of anatase type TiO₂ is confirmed by XRD. SEM measurement indicates a rough surface morphology with sharp, protruding modules after annealing treatment. Optical properties reveal an extended tailing of the absorption edge toward the visible region due to nitrogen presence. The band gap of the N-doped sample is reduced from 3.36 eV to 3.12 eV compared with the undoped one. All the N-doped samples show red shift in photoresponse towards visible region and improved photocurrent density under visible irradiance is observed for the N-doped samples.     

锂离子注入对V2O5薄膜红外振动特性影响

用反应蒸发法制备了多晶Ｖ２Ｏ５薄膜,采用两电极多锂离子电解质向Ｖ２Ｏ５薄膜注入锂离子,测试了离子注入前后薄膜的红外反射光谱,实验结果表明,锂离子注入对Ｖ２Ｏ５晶体红外振动影响较大。采用多晶Ｖ２Ｏ５振动模型分析了薄膜的红外振动吸收,并得到了锂离子注入产生的Ｖ２Ｏ５薄膜振动的变化是由于晶格扩展和钒离子自身杂质形成引起的。     

不同氧氩比例对氧化硅(SiO2)薄膜的结构及性能的影响

在不同氧氩比例气氛下,采用反应直流磁控溅射方法制备了SiO2薄膜.利用X射线衍射（XRD）、X射线光电子能谱（XPS）、原子力显微镜（AFM）和紫外可见光谱（UV-Visible spectrum）等研究了氧氩比例的不同对SiO2薄膜的晶体结构、化学配比、表面形貌和光学性能的影响.结果显示：室温下,不同氧氩比例的SiO2薄膜都为非晶结构;随着氧分量的增加,Si2p与O1s向高结合能方向移动;在氧分量较大的气氛下,SiO2薄膜的化学失配度较小,薄膜均匀,致密,在400-1100nm有良好的光透过性.