注射超声喷雾热分解方法制备ZnO薄膜研究

以乙酸锌为原料加水合成ZnO前驱液,利用注射超声喷雾热分解方法在玻璃衬底上成功制备ZnO薄膜。通过正交选择液体注射速度、注射量、衬底温度、退火温度为实验要素,通过XRD、SEM、可见光透过率分析优化的制备条件为:液体注射速度为0.2 mL/min,注射量为3 mL,衬底温度为450℃,退火温度为500℃。制备的ZnO薄膜透光率达到85%。新的制备薄膜装置采用注射超声雾化手段,克服其雾化不均问题。     

TiO2薄膜的火焰喷雾热分解法制备与自清洁研究

以钛酸丁脂(Ti(C4H9O)4)为前驱体,采用自制的火焰喷雾热分解装置在玻璃衬底上制备了TiO2自清洁薄膜.应用扫描电子显微镜(SEM)、X射线衍射(XRD)、紫外-可见透射光谱(UV-Vis)分析了薄膜的形貌、结构和透光性,并对薄膜的光催化性能和亲水性能进行了测试.结果表明,火焰喷雾热分解法制备薄膜要求雾滴先成液膜,再热分解为固体薄膜;采用火焰喷雾热分解法在玻璃衬底上成功制备的TiO2薄膜为锐钛矿晶型;探讨了沉积时间和退火温度对薄膜的结晶和自清洁性及光催化性能的影响,沉积时间长,退火温度高的薄膜的结晶度越高,光催化性能和亲水性越好;用该方法制备的温度约为400℃,退火温度为600℃薄膜,光透过率可超过70%.     

络合剂对ZnO薄膜的结构及其光电性能的影响

在400℃预处理温度下,以醋酸锌为前驱体,分别以乙醇胺、二乙醇胺和三乙醇胺为络合剂,在普通玻璃载玻片上采用溶胶-凝胶技术成功地制备了C轴择优取向的ZnO薄膜.用X射线衍射、紫外-可见吸收光谱、光致发光光谱和平行电极法等技术研究了以不同络合剂制备的ZnO薄膜的结构、缺陷组成及其光电性能.结果表明:络合剂对ZnO薄膜结构的影响很大,不同结构的薄膜,其性能也有很大的差异.其中,以乙醇胺为络合剂制备的ZnO薄膜具有最佳的(002)晶面择优取向,并能减少晶界处载流子的散射,使薄膜具有较高的光电流.     

压缩喷雾热分解法制备SnO2薄膜研究

以SnCl2·2H2O为原料,采用压缩喷雾热分解的方法在玻璃衬底和石英片衬底上制得氧化锡薄膜。采用X射线衍射仪（XRD）和扫描电镜（SEM）分别对薄膜的内部结构和表面形貌进行了表征。研究表明,500℃下制备的薄膜比较致密平整;320℃下,喷雾50min制得的薄膜的X射线衍射峰强度较强;相同喷雾时间下,当温度达到380℃时,X射线衍射峰的强度大幅度提高。     

纳米ZrO2/Al2O3复合陶瓷粉体的制备及XRD分析

以醋酸锆、硝酸铝为原料,柠檬酸作为络合剂,采用溶胶-凝胶法获得前驱体,将前驱体在空气中热分解,制备了纳米ZrO2/A l2O3复合陶瓷粉体.采用XRD考察了合成产物的结构和纯度,分析了制备过程中原料初始浓度及前驱体热分解温度对最终产物的影响.结果表明,初始浓度为0.6mol/L,热分解温度为1 200℃时,ZrO2/A l2O3复合陶瓷粉体的粒径为30~41nm.     

CdS薄膜结构表征与光电化学性能研究

以超声喷雾热分解方法成功地制备了低成本高质量的CdS薄膜,用XRD、SEM、拉曼光谱、紫外可见吸收光谱,研究了4个不同沉积温度下制备的CdS薄膜的结构性质,并对其进行光电化学产氢性能测试.实验发现,薄膜结晶程度随着沉积温度的升高而增加,但禁带宽度保持不变.SEM测试显示薄膜均匀致密,表明此方法是一种有效的半导体薄膜电极制备方法.光电化学活性随着沉积温度的升高先增大后减小,在300℃为最佳,在187mw/cm2的光照下此温度制备的电极的光电流密度饱和值约为4.1 mA/cm2,且在电极电势为-0.13 V(vs SCE)处的能量转化效率为0.68%.     

热喷涂法制备Sb掺杂的SnO_2薄膜

以SnCl4·5H2O和SbCl3为原料,采用喷雾热分解法在管状石英玻璃基材上制备出Sb掺杂的SnO透明导电薄膜,并采用X射线衍射仪(XRD)和原子力显微镜(AFM)对薄膜的结构和表面形貌进行了分析,研究了Sb掺杂量和喷涂温度对薄膜方阻及结构的影响.结果表明:当Sb掺杂量为6 mol%、成膜温度为500℃时,薄膜的方阻达到最低(65Ω/□),结构最致密.     

溶胶凝胶法制备氧化亚铜薄膜及其工艺条件

以单质锂、无水甲醇和氯化铜为原料,葡萄糖为还原剂,醋酸为络合剂,采用溶胶 凝胶法在玻璃基片上制备Cu2O薄膜,并确定了制备的工艺条件:CH3OH及CuCl2·2H2O为原材料,C6H12O6·H2O为还原剂,CH3COOH为络合剂。通过X射线衍射仪、紫外 可见分光光度计和扫描电镜等分析和表征,确定了影响Cu2O薄膜性质的因素。结果表明:用溶胶 凝胶法可以制备具有良好性能的Cu2O薄膜。     

溶胶凝胶法制备氧化亚铜薄膜及其工艺条件

以单质锂、无水甲醇和氯化铜为原料,葡萄糖为还原剂,醋酸为络合剂,采用溶胶 凝胶法在玻璃基片上制备Cu2O薄膜,并确定了制备的工艺条件:CH3OH及CuCl2·2H2O为原材料,C6H12O6·H2O为还原剂,CH3COOH为络合剂。通过X射线衍射仪、紫外 可见分光光度计和扫描电镜等分析和表征,确定了影响Cu2O薄膜性质的因素。结果表明:用溶胶 凝胶法可以制备具有良好性能的Cu2O薄膜。     

压缩喷雾热分解方法制备MgO薄膜的研究

以醋酸镁为原料,用自制的压缩喷雾热分解装置对氧化镁薄膜的制备工艺进行了详细的研究,利用X射线衍射(XRD)、扫描电镜(SEM)对薄膜的微观结构进行了分析,以期寻求到较佳的制备薄膜的条件.结果表明,为获得性能较好的Mg0薄膜,衬底温度和喷雾速率是关键因素.控制实验条件,可在600℃得到了较好的MgO薄膜,结果显示所得样品为立方MgO多晶薄膜.     

ZnO films on transferable and low thermal resistance graphite substrate grown by ultrasonic spray pyrolysis

ZnO thin films were deposited on graphite substrates by ultrasonic spray pyrolysis method with Zn(CH 3 COO) 2 ·2H 2 O aqueous solution as precursor. The crystalline structure, morphology, and optical properties of the as-grown ZnO films were investigated systematically as a function of deposition temperature and growth time. Near-band edge ultraviolet(UV) emission was observed in room temperature photoluminescence spectra for the optimized samples, yet the usually observed defect related deep level emissions were nearly undetectable, indicating that high optical quality ZnO thin fi lms could be achieved via this ultrasonic spray pyrolysis method. Considering the features of transferable and low thermal resistance of the graphite substrates, the achievement will be of special interest for the development of high-power semiconductor devices with suffi cient power durability.     

Preparation and characterization of three-dimensional chrysanthemun flower-like calcium carbonate

Calcium carbonate with three-dimensional chrysanthemun flower-like structure was successfully prepared from calcium chloride and sodium carbonate ethanol/water mixed solution by a simple precipitation method,using trisodium citrate as crystal modifier.The experimental results show that the three-dimensional structure of chrysanthemun flower-like calcium carbonate is built up with several symmetrical micrometer multi-layer petals arranged around the multi-layer pancake-liked center,and the micrometer center and petals are assemblied by a large number of nanometer spherical particles with size 10-20 nm.It is found that the amount of trisodium citrate,the ethanol volume content has an important influence on the formation of this morphology.A possible mechanism is proposed to explain the formation of three-dimensional chrysanthemun flower-like calcium carbonate according the results.Scanning electron microscopy(SEM),X-ray powder diffraction(XRD),flourier transform infrared spectroscopy(FT-IR),thermogravimety analysis(TG),transmission electron microscopy(TEM) equipped with energy-dispersive X-ray(EDX),and selected area electron diffraction(SAED) were used to characterize the crystals.     

CuxS(x=1,2)纳米薄膜的异步脉冲超声喷雾热解法制备

采用改进的异步脉冲超声喷雾热解技术在玻璃衬底上成功地制备了CuxS(x =1,2 )纳米薄膜 .研究发现 ,所制备的CuxS薄膜为多晶态 ;薄膜的晶相结构依赖于CuCl2 ·2H2 O和硫脲的摩尔比及衬底温度 .XRD和XPS分析表明 :样品为纯CuxS(CuS ,Cu2 S) ,拉曼谱研究表明其峰位分别在 472cm- 1 (Cu2 S)和 474cm- 1 (CuS)处 .     

BiSI棒状纳米晶薄膜的物性研究

采用改进的喷雾热解方法——异步脉冲超声喷雾热解法（APUSP），以BiCl3、硫脲和碘溶液为前驱液，在非晶衬底上成功地制备了BiSI纳米棒阵列薄膜．对采用异步脉冲超声喷雾热解法所制备的棒状BiSI纳米晶薄膜样品的介电特性和光吸收特性进行了测试．结果表明，采用该法所制备的棒状纳米结构薄膜与传统喷雾热解法所制备的薄膜，由于结构的不同，其介电特性和可见光吸收特性具有明显的区别．该方法与传统喷雾热解法相比，所制备的纳米晶薄膜具有较高的介电常数、较小的介电损耗和较大的光吸收强度，     

Synthesis and Properties of Water-soluble CdSe/ZnS Nanocrystals with the Type-Ⅰ Core/Shell Structure

The synthesis of CdSe/ZnS core/shell nanocrystals though aqueous phase using the coprecipitation method was reported. The influences of factors such as injection methods and dosages of precursors, reaction duration of water-bathing and the initial CdSe:ZnS molar ratio were discussed. In comparison to the CdSe plain core nanocrystals, the CdSe/ZnS core/shell nanocrystals show much brighter photoluminescence demonstrated by the photoluminescence spectra. The epitaxial growth of the core/shell structures was verified by TEM and XRD.     

沉积温度对ZnO薄膜结构形貌及光学性能的影响

以Zn(NO3)2·6H2O为前驱体,采用超声喷雾热解法在玻璃衬底上沉积了ZnO薄膜,采用X射线衍射(XRD)、扫描电子显微镜(SEM)、紫外光谱仪(UVS)等对所得ZnO薄膜进行表征,研究了沉积温度对ZnO薄膜的结构、微观形貌及光学性能的影响。结果表明,沉积温度为500℃时所制备的薄膜质量最佳,形成的是六角纤锌矿ZnO结构,且薄膜沿(002)晶面择优取向生长显著,薄膜表面光滑致密,晶粒细小均匀,尺寸在50~60nm。薄膜表现出良好的光学性能,可见光透过率可达87%。     

纳米异质粒子对燃油射流喷雾特性的影响

选用平均粒径为20 nm的CeO₂纳米粒子,以油酸为表面活性剂,采用两步法配制质量浓度分别为50与100 mg/L的纳米燃油,分别称为Ce50和Ce100燃油;测量柴油和纳米燃油的密度、黏度和表面张力等基础物性参数;在高压共轨喷雾试验台上拍摄燃油射流喷雾发展过程的影像,应用Matlab软件处理影像,得到喷雾贯穿距和喷雾锥角等特性参数. 结果表明：与柴油相比,Ce50和Ce100纳米燃油的黏度分别增加了2.1%与4.7%,密度和表面张力的增加量较小. 在相同喷射压力下的不同喷雾发展时刻,纳米燃油的油束贯穿距大于柴油,喷雾锥角略小于柴油. 在背压为2 MPa、喷射压力分别为80、120和160 MPa时,与柴油相比,Ce50纳米燃油的喷雾贯穿距分别增加了1.4、1.9和2.4 mm,Ce100纳米燃油的贯穿距分别增加了2.9、2.9和3.7 mm. 随着喷射压力的提高,纳米燃油与柴油在喷雾贯穿距和喷雾锥角上的差异增大. 当燃油喷射背压增加时,油束的贯穿距缩短而喷雾锥角增大,不同质量浓度纳米燃油和柴油的贯穿距和喷雾锥角的差异有所减小.     

Synthesis and properties of water-soluble CdSe/ZnS nanocrystals with the type-I core/shell structure

The synthesis of CdSe/ZnS core/shell nanocrystals though aqueous phase using the coprecipitation method was reported. The influences of factors such as injection methods and dosages of precursors, reaction duration of water-bathing and the initial CdSe：ZnS molar ratio were discussed. In comparison to the CdSe plain core nanocrystals, the CdSe/ZnS core/shell nanocrystals show much brighter photoluminescence demonstrated by the photoluminescence spectra. The epitaxial growth of the core/shell structures was verified by TEM and XRD.