CdSZnO核壳纳米棒阵列结构的制备及在太阳能电池中的应用

采用水热法制备垂直于FTO导电玻璃基底的ZnO纳米棒阵列,然后通过电化学沉积法在ZnO纳米棒阵列上沉积CdS纳米晶,形成CdS/ZnO核壳纳米棒阵列结构。利用扫描电子显微镜(SEM)、X射线衍射仪(XRD)、X射线能谱仪(EDS)和紫外-可见分光光度计(UV-Vis)等对所得样品的形貌、结构组成进行分析表征;并以其为光电极组装太阳能电池,研究CdS纳米晶厚度对该电池光电性能的影响。结果表明,所得样品不仅拓宽和加强电池的光吸收能力,也有效调控光生载流子的传输。当CdS纳米晶沉积时间为60s时,电池的光电转换效率最高可达1.10%。     

电化学沉积法制备纳米多孔ZnO/曙红复合薄膜

以Zn(NO3)2和曙红的混合溶液为沉积液,采用阴极电化学沉积法在ITO导电玻璃上制备了纳米多孔ZnO/曙红复合膜.考察了电化学预处理过程和曙红浓度对薄膜晶体结构、微观形貌和光学性能的影响.结果表明,引入短时间的电化学预处理过程能提高复合薄膜中ZnO的结晶质量,并诱导ZnO沿c轴定向生长.随着电沉积液中染料浓度的增大,所得薄膜的结晶质量下降,薄膜由六角晶颗粒逐渐向纳米多孔结构转变.当沉积液中曙红浓度为50μmol/L 时所得复合薄膜具有最大膜厚,装载的曙红量最高.以该复合膜为光阳极制作了太阳能电池原型器件,其开路电压为0.49V,短路电流为0.67mA/cm2,总光电转换效率为0.105%.     

ZnS/ZnO纳米片组装多孔微球的制备及其传感特性研究

将水热法制备的ZnS纳米球500℃保温2h制备出由ZnS、ZnO纳米片组装的多孔微球。利用扫描电子显微镜、X射线衍射仪和透射电子显微镜对样品的形貌和结构进行了表征。测试多孔ZnS/ZnO微球传感器对不同浓度的乙醇、三乙胺和丙酮的传感性能,并讨论其增强的响应机理。     

性能增强的双层TiO2复合膜染料敏化太阳能电池

采用水热法制备了一维TiO₂纳米棒阵列、二维TiO₂纳米片和三维TiO₂微球。将TiO₂纳米棒阵列/纳米片-微球双层薄膜应用于染料敏化太阳能电池(DSSC), 研究了TiO₂纳米片与微球的质量比对电池光电性能的影响。采用场发射扫描电镜、氮气吸附脱附等温线、X射线衍射、紫外-可见漫反射光谱、荧光光谱和电化学阻抗谱对样品进行了表征。研究表明, 纳米片与微球的质量比显著影响膜电极的光学和电学特性, 以及电池的光电性能。含50wt% TiO₂纳米片膜电极具有最高的染料吸附量、最强的光吸收、最小的传输电阻和最低的荧光强度。含25wt%、50wt%、75wt%和100wt%纳米片的DSSC的效率分别为1.46%、1.71%、1.26%和1.13%。含50wt% 纳米片的电池具有最优的性能, 这是因为该组分电极具有较好的光吸收特性、较小的载流子复合速率以及较快的电子传输。     

ZnO纳米棒阵列膜的制备及其光电化学性能研究

采用化学溶液沉积法,在ZnO纳米颗粒膜修饰的FTO导电玻璃基底上,制备了ZnO纳米棒阵列。用X射线衍射仪（XRD）、场发射扫描电子显微镜（FESEM）、透射电子显微镜（TEM）对样品进行表征。研究结果表明所制备的ZnO纳米棒为六方纤锌矿相单晶结构,沿c轴择优取向生长,平均直径约为40nm,长度约为900nm;ZnO纳米棒阵列生长致密,取向性较一致。以曙红Y敏化的ZnO纳米棒阵列膜为光阳极制作了染料敏化太阳能电池原型器件,在光照强度为100mW/cm2下,其开路电压为0.418V,短路电流为0.889mA/cm2,总的光电转换效率为0.133%。     

TiO2纳米管与纳米线的光电化学研究

利用在钛箔表面沉积一层TiO2纳米粒子作为晶种,与NaOH反应,通过改变反应温度制备了TiO2纳米管与纳米线.制备了TiO2纳米管和纳米线膜电极,并进行了光电化学测试.光电化学实验表明,混晶结构TiO2纳米管和纳米线显示出优良的光电转化性能.     

染料敏化太阳能电池MO／TiO2复合薄膜的制备与表征

用溶胶-凝胶法结合旋转镀膜法制备致密TiO2薄膜，采用丝网印刷技术制备多孔TiO2薄膜，采用液相沉积法制备ZnO／Ti02、MgO／TiO2复合薄膜。用x射线能谱仪、原子力显微镜、紫外-可见分光光度计对复合薄膜的化学组分、表面形貌、吸光性能等进行分析；组装电池，测定了电池性能。结果表明：ZnO／TiO2、MgO／TiO2复合薄膜具有较好的光电性能，染料敏化太阳能电池的短路电流、开路电压、填充因子、光电转换效率均得到提高。     

Cu_2O敏化ZnO纳米棒的制备及其对光电性质的影响

以透明导电玻璃(FTO)为基底,采用电化学沉积法制备了Cu_2O敏化的ZnO纳米棒阵列复合薄膜。利用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、透射电镜(TEM)、高分辨电镜(HRTEM)、电化学工作站研究了不同Cu_2O沉积时间对复合薄膜的晶体结构、形貌、光电性质的影响。结果表明,电化学沉积的Cu_2O纳米晶可以与ZnO纳米棒形成异质结,提高ZnO纳米薄膜的光电转换效率,当Cu_2O的沉积时间为5min时,Cu_2O敏化ZnO纳米棒薄膜的光电转换效率最高。     

纳米晶ZnS薄膜的制备方法及应用进展

纳米晶ZnS薄膜具有带隙宽度大、光学透过率高、介电常数低、化学稳定性好等特点,在透明导电膜、铜铟镓硒(CIGS)薄膜太阳能电池、发光器件、功能玻璃等领域表现出巨大的应用潜力。综述了纳米晶ZnS薄膜常用的制备方法,如磁控溅射法、化学浴沉积法、真空蒸发法和化学气相沉积法,同时还介绍了纳米晶ZnS薄膜的掺杂改性研究及其在相关领域的应用进展。     

自持金刚石厚膜上沉积ZnO薄膜的研究

ZnO/金刚石结构的表面声学波滤波器的性能主要取决于沉积ZnO薄膜的质量.本文用金属有机化合物气相沉积两步生长法在自持化学气相沉积金刚石厚膜的成核面上制备了ZnO薄膜,并用X射线衍射谱,扫描电子显微镜和室温光荧光谱对薄膜质量进行了表征.结果表明得到的ZnO薄膜取向一致,表面较均匀,光学质量良好.     

PbS量子点/ZnO纳米片复合膜的制备及其光电化学性能

通过两步法合成PbS量子点(QDs)修饰ZnO纳米片复合膜. 首先利用电化学法在掺氟的SnO₂导电玻璃(FTO)上生长ZnO纳米片, 然后在ZnO纳米片上通过逐次化学浴法沉积PbS量子点形成PbS/ZnO复合膜. 利用扫描电子显微镜(SEM)、X射线衍射仪(XRD)详细表征了样品的表面形貌和晶体结构, 并研究了PbS/ZnO复合膜作为量子点敏化太阳能电池光阳极的紫外-可见吸收谱、光电化学性能和表面光电压谱. 对比ZnO纳米片经PbS量子点修饰前后, 发现PbS量子点修饰后光阳极的光吸收和光伏响应均从紫外区拓宽到了可见光区, 同时光电化学性能有了显著提高, 短路电流密度从敏化前的0.1 mA/cm²增加到0.7 mA/cm², 效率由0.04%增加到0.57%. 与单一ZnO纳米片相比, PbS/ZnO复合膜的表面光伏响应强度明显增强, 说明PbS与ZnO之间形成了有利于光生电荷分离的异质结, 从而导致了PbS/ZnO复合膜光电性能的增加.     

Fabrication and characterization of a composite ZnO semiconductor as electron transporting layer in dye-sensitized solar cells

ZnO nanocomposites involving nanowires and nanoparticles with a thickness of 4 μm were grown by chemical bath deposition and used as electron transporting layer in dye-sensitized solar cells (DSSCs). The growth of ZnO nanowires was initially achieved in a zinc nitrate and hexamethylenetetramine aqueous solution on a fluorine-doped tin oxide thin film seeded with ZnO nanoparticles. Subsequently, layered hydroxide zinc acetate (LHZA) nanoparticles were deposited on the nanowires by dip coating in a zinc acetate methanolic solution. A relatively conformal deposit of nanoparticles all along the nanowires was revealed by scanning and transmission electron microscopy. It is shown by X-ray diffraction measurements that a subsequent annealing convert the LHZA nanoparticles into ZnO nanoparticles. The resulting DSSCs present a short circuit current density almost three times higher when the ZnO nanowire interstices were filled with ZnO nanoparticles, which is due to a higher dye loading for a constant device thickness. This is correlated with a very high specific surface area in ZnO nanocomposites, which is 250 times larger than the geometrical surface area. Although a decrease in both the open circuit voltage and the fill factor was shown by electrochemical impedance spectroscopy owing to an increase in electron radiative and nonradiative recombinations, the efficiency of ZnO nanocomposite-based-DSSCs was on average 1.75%, which is 70% higher than for single ZnO nanowire-based-DSSCs.     

Tin sulfide thin films and Mo/p-SnS/n-CdS/ZnO heterojunctions for photovoltaic applications

Tin sulfide (SnS) is one of the most promising materials for photovoltaics. Here we report on the preparation as well as chemical, structural and physical characterization of the Mo/p-SnS/n-CdS/ZnO heterojunctions. The SnS thin films were grown by hot wall deposition method on the Mo-coated glass substrates at 270-350 °C. The crystal structure and elemental composition were examined by X-ray diffraction and Auger electron spectroscopy methods. The CdS buffer layers were deposited onto the SnS films by chemical bath deposition. The ZnO window layers were deposited by a two step radio frequency magnetron sputtering, resulting in a ZnO bilayer structure: the first layer consists of undoped i-ZnO and the second of Al-doped n-ZnO. The best junctions have an open circuit voltage of 132 mV, a short circuit current density of 3.6 mA/cm², a fill-factor of 0.29 and efficiency up to 0.5%.     

Dye-sensitized solar cells based on ZnO nanoflowers and TiO2 nanoparticles composite photoanodes

ZnO nanoflowers were synthesized by low temperature solution-phase method. ZnO nanoflowers/TiO₂ nanoparticles composite photoanodes with various mass ratios were prepared on transparent conductive fluorine-doped tin oxide substrates by doctor-blade technique. The dye-sensitized solar cells (DSSCs) were assembled. The morphology characteristics of ZnO nanoflowers and ZnO/TiO₂ composite photoanodes have been analyzed by scanning electron microscopy. The effect of the ZnO nanoflowers/TiO₂ nanoparticles mass ratio on the performance of DSSCs was systematically investigated by I–V characteristics and electrochemical impedance spectroscopy. Results show that the conversion efficiency of the dye-sensitized solar cell with a ZnO/TiO₂ mass ratio of 25:75 was increased by about 35 % compared to that of pure TiO₂-based solar cell. Addition of ZnO nanoflowers can enhance the light harvesting and improve electron transport.     

High quality ZnO films deposited by radio-frequency magnetron sputtering using layer by layer growth method

Three-layered ZnO films were deposited on Si substrates by radio-frequency magnetron sputtering using layer by layer growth method. The Raman scattering confocal analysis confirms that ZnO film quality is improving at increasing the number of ZnO layers at film deposition.Applied method of deposition was used to realize homoepitaxial growth of ZnO films on c-Al₂O₃, Si, SiN_x/Si, glass and ITO/glass substrates. In order to improve the film quality we increased the number of deposition stages up to 5. X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmittance measurements were used to testify the quality of grown five-layered ZnO films. XRD results showed that all five-layered ZnO films have (002) texture. The second order diffraction peak (004) on XRD spectra additionally testifies to the high quality of all five-layered ZnO films. SEM results demonstrated that no defects such as cracks and dislocations caused by interruption of deposition ZnO films were observed. Transmittance measurement results showed that ZnO films deposited on transparent substrates have abrupt absorption edge and high optical transmission in the visible region of the spectrum.     

Photovoltaic performance of dye-sensitized solar cell low temperature growth of ZnO nanorods using chemical bath deposition

Nanostructured ZnO photoelectrodes were synthesized on fluorine-doped tin oxide (FTO) glass substrates that were spin-coated with a sol-gel based ZnO seed layer via a chemical bath deposition (CBD) method at varying times of 1, 2, 4, and 8 h. Then, TiO2 nanoparticulate electrodes were prepared on ZnO nanorods using the doctor blade technique. The uniformly grown ZnO nanorod layer had a length of approximately 710 nm on the FTO glass substrate with wurtzite structures which was confirmed through X-ray diffraction patterns. The length and diameter of the ZnO nanorods increased with an increase in the deposition time. The DSSCs fabricated with TiO2 nanoparticulate/grown ZnO nanorods and grown for 8 h showed the maximum efficiency (5.51%) with a short circuit current density (J(sc)) of 12.21 mA/cm2 and an open circuit voltage (V(oc)) of 0.70 at 100 mW/cm2 light intensity.     

Nanostructured ZnO network films deposited on Al2O3 substrates by chemical bath deposition

Nanostructured ZnO network films have been fabricated on Al₂O₃ substrates by the combination of chemical bath deposition and thermal decomposition process. Layered basic zinc nitrate (LBZN) network films were deposited on the Al₂O₃ substrates with LBZN crystal seeds in methanol solution of zinc nitrate hexahydrate and hexamethylenetetramine. The LBZN precursor films were then transformed into nanostructured ZnO films by heating at 260 °C in air. During the thermal decomposition process abnormal exothermic heat effect was observed at 200-210 °C and CH₃ groups were found in the as-deposited films. We propose that methanol molecules are integrated in the LBZN films forming LBZN-CH₃OH complex and that the heat effect comes from the exothermic release of the methanol.     

One-step synthesis of CdS sensitized TiO₂ photoanodes for quantum dot-sensitized solar cells by microwave assisted chemical bath deposition method

Sensitized-type solar cells based on TiO? photoanodes and CdS quantum dots (QDs) as sensitizers have been studied. CdS QDs are grown on TiO? films, utilizing one-step microwave assisted chemical bath deposition (MACBD) method. This method allows a facile and rapid deposition and integration between CdS QDs and TiO? films. The photovoltaic performances of the cells fabricated using CdS precursor solutions with different concentrations are investigated. The results show that the cell based on MACBD deposited TiO?/CdS electrode achieves a maximum short circuit current density of 7.20 mAcm?2 and power conversion efficiency of 1.18 % at one sun (AM 1.5G, 100 mW cm?2), which is comparable to the ones prepared using conventional techniques.     

ZnO纳米四脚状阵列电极染料敏化太阳能电池

采用化学气相沉积(CVD)法制备了不同尺寸的四脚状纳米ZnO和ZnO纳米棒。采用X射线粉末衍射(XRD)、扫描电子显微镜(SEM)对纳米ZnO的晶型结构和形貌进行表征,研究结果表明CVD法制备的四脚状纳米ZnO具有三维空间结构,其最小平均臂宽约为70nm,臂长约300nm,制备的纳米棒直径约为84nm,长约2μm,且都为六方纤锌矿晶型结构。将ZnO纳米四脚状及纳米棒利用滚涂法在FTO导电玻璃上形成ZnO光阳极,经N719染料敏化后组装成染料敏化太阳能电池,光电性能结果表明,染料敏化小尺寸的四脚状纳米ZnO太阳能电池光电转换效率(η=1.88%)高于染料敏化大尺寸的四脚状纳米ZnO太阳能电池光电转换效率(η=1.18%),远高于染料敏化ZnO纳米棒太阳能电池的光电转换效率(η=0.7%)。