Comparison between P25 and anatase-based TiO<Subscript>2</Subscript> quasi-solid state dye sensitized solar cells

Pure anatase TiO2 films have been made via hydration of titanium isopropoxide using a sol-gel tech-nique, while mixed TiO2 films which contained both anatase and rutile TiO2 were made from commercial P25 powder. Quasi-solid state dye-sensitized solar cells were fabricated with these two kinds of mesoporous films and a comparison study was carried out. The result showed that the open-circuit photovoltages （Voc） for both kinds of cells were essentially the same, whereas the short-circuit photo-currents （1sc） of the anatase-based cells were about 33% higher than that of the P25-based cells. The highest photocurrent intensity of the anatase-based cell was 6.12 mA/cm^2 and that of the P25-based cell was 4.60 mA/cm^2. Under an illumination with the light intensity of 30 mW/cm^2, the corresponding energy conversion efficiency was measured to be 7.07% and 6.89% for anatase-based cells and P25-based cells, respectively.     

Comparison between P25 and anatase-based TiO_2 quasi-solid state dye sensitized solar cells

Pure anatase TiO2 films have been made via hydration of titanium isopropoxide using a sol-gel tech- nique, while mixed TiO2 films which contained both anatase and rutile TiO2 were made from commercial P25 powder. Quasi-solid state dye-sensitized solar cells were fabricated with these two kinds of mesoporous films and a comparison study was carried out. The result showed that the open-circuit photovoltages (Voc) for both kinds of cells were essentially the same, whereas the short-circuit photo- currents (Isc) of the anatase-based cells were about 33% higher than that of the P25-based cells. The highest photocurrent intensity of the anatase-based cell was 6.12 mA/cm2 and that of the P25-based cell was 4.60 mA/cm2. Under an illumination with the light intensity of 30 mW/cm2, the corresponding en- ergy conversion efficiency was measured to be 7.07% and 6.89% for anatase-based cells and P25-based cells, respectively.     

Fabrication and characterization of TiO2 -based dye-sensitized solar cells

Dye-sensitized solar cells TiO_2 with were fabricated.The phase composition and microstructures of the solar cells were examined by X-ray diffractometry and transmission electron microscopy,and the energy levels of the present solar cells were also discussed.The results show that a solar cell mixed with xylenol orange and rose Bengal shows a higher conversion efficiency compared to solar cells with a single dye.An introduction of amorphous TiO_2 layers results in an improvement of the conversion efficien...     

Thermodynamics and phase transformations in the recovery of zinc from willemite

Willemite is a common component of zinc and lead metallurgical slags that, in the absence of effective utilization methods, cause serious environmental problems. To solve this problem and increase zinc recovery, we proposed a novel extraction method of zinc from willemite by calcified roasting followed by leaching in NH₄Cl-NH₃·H₂O solution. The thermodynamics and phase conversion of Zn₂SiO₄ to zinc oxide (ZnO) during calcified roasting with CaO were investigated. The mechanism of mineralogical phase conversion and the effects of the CaO-to-Zn₂SiO₄ mole ratio (n(CaO)/n(Zn₂SiO₄)), roasting temperature, and the roasting time on zinc-bearing phase conversion were experimentally investigated. The results show that Zn₂SiO₄ was first converted to Ca₂ZnSi₂O₇ and then to ZnO. The critical step in extracting zinc from willemite is the conversion of Zn₂SiO₄ to ZnO. The zinc percent leached in the ammonia leaching system rapidly increased because of the gradual complete phase conversion from willemite to ZnO via the calcified roasting process.     

Preparation of Cu（In,Ga）Se2 thin film by sputtering from Cu（In,Ga）Se2 quaternary target

Cu(In,Ga)Se2 (CIGS) thin films were prepared by directly sputtering Cu(In,Ga)Se2 quaternary target consisting of Cu:In:Ga:Se 25:17.5:7.5:50 at%. The composition and structure of CIGS layers have been investigated after annealing at 550 ℃ under vacuum and a Se-containing atmosphere. The results show that recrystallization of the CIGS thin film occurs and a chalcopyrite structure with a preferred orientation in the (112) direction was obtained. The CIGS thin film annealed under vacuum exhibits a loss of a portion of Se, while the film annealed under Se-containing atmosphere reveals compensation of Se. Several solar cells with three different absorber thicknesses were fabricated using a soda lime glass/Mo/CIGS/CdS/i-ZnO/ZnO:Al/Al grid stack structure. The highest conversion efficiency of 9.65% with an open circuit voltage of 452.42 mV, short circuit current density of 32.16 mA cm2 and fill factor of 66.32% was obtained on a 0.755 cm2 cell area.     

Temperature dependent spectral response characteristic of III-V compound tandem cell

The GaInP/GaAs/Ge triple-junction tandem cells with a conversion efficiency of 27.1% were fabricated using metalorganic chemical vapor deposition (MOCVD) technique. Temperature dependence of the spectral response measurements of the GaInP/GaAs/Ge tandem cell was performed by a quantum effi-ciency system at temperatures ranging from 25℃ to 160℃. The red-shift phenomena of the absorption limit for all subcells were observed with increasing temperature, which is dued to the energy gap nar-rowing with temperature. The short-circuit current densities (J_sc)of GaInP, GaAs and Ge subcells at room temperature calculated based on the spectral response data were 12.9, 13.7 and 17 mA/cm², re-spectively. The temperature coefficient of J_sc for the tandem cell was determined to be 8.9 mA/(cm²·℃), and the corresponding temperature coefficient of the open-circuit voltage deduced from the se-ries-connected model was -6.27 mV/℃.     

Development and Experimental Research of kW—scale Molten Carbonate Fuel Cells

A kW-scale moten carbonate fuel cells stack was developed and 800-hours‘ operating test and performance experimental research had been done.Utilizing domestic materials completely,we developed NiO cathode and Ni-Al aonde with the active area of 336cm^2 and γ-LiAlO2 electrolyte tile and bipolar plate with the area of 900cm^2,The stack was composed of thirth cells,with 62% Li2CO3 38% K2CO3 as its electrolyte,During the 800hours continuous operating,the performance of the stack was stable.With 99.7%(mole fraction)H2 as fuel and O2 from air as oxidant,the average operating voltage of a cell was about 0.72V.The maximal current density attained to 165mA/cm^2.and the maximal output power attained to 1080Watt.The whole perfomance of the stack approached to the international level in the early 90‘s ,This paper gives the main works and experimants results.     

Hydrogen production by reforming methane in a corona inducing dielectric barrier discharge and catalyst hybrid reactor

A novel corona inducing dielectric barrier discharge(CIDBD) and catalyst hybrid reactor was developed for reforming methane. This corona inducing technique allows dielectric barrier discharge(DBD) to occur uniformly in a large gap at relatively low applied voltage.Hydrogen production by reforming methane with steam and air was investigated with the hybrid reactor under atmospheric pressure and temperatures below 600°C.The effects of input power,O2/C molar ratio and preheat temperature on methane conversion and hydrogen selectivity were investigated experimentally.It was found that higher methane conversions were obtained at higher discharge power,and methane conversion increased significantly with input power less than 50 W;the optimized molar ratio of O2/C was 0.6 to obtain the highest hydrogen selectivity(112%);under the synergy of dielectric barrier discharge and catalyst,methane conversion was close to the thermodynamic equilibrium conversion rate.     

Medium Optimization of Tetraselmis sp.—1 Using Response Surface Methodology

Response surface methodology (RSM) is used to optimize the medium of Tetraselmis sp.-1 which is cell fused microalgae capable of growing under mixotrophie condition. Empirical models are developed to describe the relationships between the operating variables (glucose, urea, sodium dehydrogenate phosphate, sodium chloride) and responses (cell density). Statistical analysis indi-cates that glucose and urea have significant effects on the microalgae cell density, but other two factors (sodium dehydrogenate phosphate, sodium chloride) have no obvious effect. The path of steepest ascent is used to approach the optimal region of medium ecanposition. Optimal cell density(2. 638 g dry weight/L) was reached when the operating conditions were glucose concentration(30.75 % ), urea concentration (0.440 g/L), sodium dehydrogenate phosphate (15mg/L) and sodium chloride (28 g/L).     

Flexible dye-sensitized solar cell based on PCBM/P3HT heterojunction

Using blend heterojunction consisting of C60 derivatives [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) and poly(3-hexylthiophene) (P3HT) as charge carrier transferring medium to replace I3–/I– redox electrolyte,a novel flexible dye-sensitized solar cell (DSSC) is fabricated.The characterization of infrared spectra and ultraviolet-visible spectra shows that the PCBM/P3HT heterojunction has not only the absorption in ultraviolet light for PCBM,but also the absorption in visible and near infrared light for P3HT,which widens the photoelectric response range for DSSC.The influence of PCBM/P3HT mass ratio on the performance of the solar cell is discussed.Under 100 mW cm–2 (AM 1.5) simulated solar irradiation,the flexible solar cell achieves a lightto-electric energy conversion efficiency of 1.43%,open circuit voltage of 0.87 V,short circuit current density of 3.0 mA cm–2 and fill factor of 0.54.     

Nd掺杂对ZnO带隙及染料敏化太阳能电池光电性能的影响

利用溶液法制备Nd掺杂ZnO,并通过X射线衍射(XRD)、紫外-可见吸收光谱(UV-Vis)和光电流密度-光电压曲线研究Nd掺杂对ZnO带隙及染料敏化太阳能电池光电性能的影响.结果表明:Nd原子取代Zn原子掺杂到ZnO晶格中;Nd掺杂使ZnO带隙窄化,导致其UV-Vis谱吸收带边红移,且随着掺杂摩尔分数的增加,红移和窄化程度增大;掺杂Nd可提高电池的光电流及光电转换效率,当掺杂Nd的摩尔分数分别为0.5%,1.0%,1.5%时,其光电流密度分别为9.51,13.01,10.79mA/cm2,光电转换效率分别为2.28%,2.84%,2.48%.     

一种咔唑-苯并噻二唑共聚物的合成与光伏性能研究

以N-十二烷基-2,7-咔唑为给体单元、5,6-二辛氧基二噻吩苯并噻二唑为受体单元，通过Suzuki偶联反应合成了一种具有给-受体结构的共轭聚合物聚N-十二烷基-2,7-咔唑-5,6-二辛氧基-4,7-二噻吩-2-基-苯并噻二唑（PC-DODTBT），并研究了该聚合物的光物理与电化学性能。结果表明，以PC-DODTBT为电子给体，PCBM为电子受体，制得的共混体相异质结太阳能电池在AM1.5、100 mW/cm²模拟太阳光下，开路电压为0.88 V，短路电流为2.04 mA/cm²，填充因子为0.51，能量转换效率为0.92%。     

带有CGL：B：C的大面积a－Si：H太阳电池的研制

报导了在Ｐ／Ｉ界面引入ＣＧＬ：Ｂ：Ｃ＊缓冲层对大面积（２７９０ｃｍ２）单结集成Ｐ－Ｉ－Ｎ型。ａ－ＳＩ：Ｈ太阳电池性能影响的研究结果．实验发现：带有ＣＧＬ：Ｂ：Ｃ层的ａ－ＳＩ：Ｈ太阳电池性能的提高主要是填充因子ＦＦ的增加所导致，实验所得电池的ＦＦ平均达６０．３３％，平均有效面积转换效率ＦＦ达６．０％，分别比目前的生产水平（ＦＦ＝５３．９％，ＥＦ＝５３％）提高了１１．９９％和１３．２％．最后，依据建立的电池能带模型，从理论上解释了引入ＣＧＬ：Ｂ：Ｃ后电池性能得以提高的原因．     

NiO/TiO2纳米管阵列异质结电极的制备及光电化学性能

采用阳极氧化方法在金属钛表面制备TiO2纳米管阵列,管内径为60~90 nm,壁厚约为15 nm,长度为600 nm,通过化学镀Ni并结合空气中热处理过程,在TiO2表面生长出NiO纳米颗粒层,厚度约为200 nm,颗粒尺寸为20~40 nm,获得异质结型NiO/TiO2纳米管阵列复合电极.结果表明,在100 mW/c...     

空间用高效率硅太阳电池

本文阐述空间用高效率PESC硅太阳电池的理论设计和工艺实验研究.将电池设计为浅结密栅,在前表面热生长一超薄SiO_2钝化层,并制作了双层减反射膜,使电池的开路电压、短路电流和填充因子都得到较大改进.在AM1.5光照条件下,短路电流密度高达37.4 mA/cm~2,光电转换效率达到18.03%.     

铝合金表面有色钛/锆转化膜的成膜机理及性能

为了解决工业生产中钛/锆转化膜无色的问题,通过向含钛/锆的处理液中加入单宁酸及成膜促进剂,在铝合金表面制备了有色钛/锆转化膜.采用X射线能谱仪、扫描电镜、傅里叶变换红外光谱仪、X射线衍射仪、X射线光电子能谱仪和电化学工作站对转化膜的形成过程、形貌、组织结构、耐蚀性等进行了分析.结果表明:在铝合金表面成功制备出了金黄色、耐蚀性优异的转化膜,其主要成分是Na3AlF6,其次是单宁酸水解产物的金属络合物以及少量Al2O3.3H2O、TiO2等;膜的形成可分为Na3AlF6晶体成核、生长和金属络合物的沉积3个阶段;转化膜的腐蚀电流密度由基体的5.894μA/cm2下降到0.283μA/cm2,耐蚀性明显提高.     

全固态染料敏化纳米二氧化钛/铜酞菁复合太阳能电池

利用铜酞菁空穴传输材料制备了全固态染料敏化纳米TiO2太阳能电池.研究了铜酞菁厚度对电池性能的影响,结构优化后,得到的性能参数,开路电压约为618 mV,短路电流约为0.24 mA/cm2(氙灯照射,光强约为80 mW/cm2),注入因子为54.5%,总光电转换效率为0.1%.对铜酞菁层进行碘掺杂后,电池的短路电流得到了提高,而开路电压有所下降.电池暗反应研究表明,电流的升高是由于碘掺杂导致载流子浓度增大,载流子输运能力增强,电压的下降则是由于碘的掺入削弱了电池的整流特性.     

222Rn/220Rn绝对测量小闪烁室的ZnS(Ag)涂层厚度确定

ZnS(Ag)涂层厚度会影响222 Rn/220 Rn绝对测量小闪烁室的探测效率.用241 Amα电镀参考源对厚度为10 mg/cm2的ZnS(Ag)涂层α探测效率进行了实验验证.分别采用解析方法与MCNP模拟方法计算了相对立体角修正因子,讨论了空气层对α粒子的吸收修正,分析了不确定度来源.实验结果表明,10 mg/cm2 ZnS(Ag)涂层对α粒子的探测效率在102.4%～103.1%之间,不确定度小于5.44%.在实验不确定度范围内,可认为其对α粒子的探测效率为100%.实验证明了222Rn/220Rn绝对测量小闪烁室内采用10 mg/cm2厚的ZnS(Ag)涂层是可行的.     

北京城市湖泊沉积物中微生物磷脂的分布特征

以北京市城市湖泊八一湖柱状沉积物为研究对象,通过Bligh和Dyer萃取方法,萃取4个采样点柱状沉积物每2 cm分层中的磷脂,使用水质总磷的钼酸铵分光光度法（GB 11893-89）测定分层中磷脂浓度,按照Findlay给出的转换因子（1 nmol磷相当于3.4×107个微生物细胞）,估算出各样点平均微生物含量及分层的微生物量含量。现场测定水体中的pH值、DO、叶绿素等指标,表明八一湖整体水质状况良好。结果表明：八一湖4个采样点磷脂的平均含量分别为1.581μg/gdw,6.741μg/gdw,0.696μg/gdw,2.143μg/gdw。水平分布上,位于湖泊中心的2号采样点磷脂平均含量远高于其他三个采样点的磷脂含量。湖中心水流速缓慢,水流基本没有流动,大量的外源营养物质不能够及时扩散,大部分都会沉淀下来。在垂直分布上,各采样点磷脂含量均随沉积物深度的增加而降低。表层（0 cm～4 cm）磷脂含量的下降趋势相似,均呈现出2 cm分层磷脂含量为4 cm分层磷脂含量的2～3倍;而（4 cm～10 cm）各采样点磷脂含量的下降趋势各不相同。根据Findlay给出的转换因子,沉积物中微生物的含量变化趋势和磷脂含量一致表层（0～6 cm）沉积物微生物含量高,微生物活动活跃,深层（6 cm～10 cm）微生物含量低,微生物活动缓慢。