真空蒸发制备Cd(Se,S)薄膜及其光学性能研究

利用真空蒸发技术在CdS粉末中掺入不同比例的Se粉末作源,选择合适的工艺条件在玻璃衬底上获得了性能稳定的Cd(Se,S)薄膜,薄膜为纤锌矿结构,具有沿[002]晶向的择优取向.Cd(Se,S)薄膜为n型材料,在可见光范围内具有良好的透过率.随Se成分的增加,薄膜由透明橘黄色变为透明棕红色,吸收限向长波方向移动.     

水热／溶剂热法制备Mn3O4纳米材料的研究进展

Mn3O4广泛应用于催化、电化学、软磁材料、空气净化等领域。近年来，采用多种新技术研制Mn3O4新材料，如电子级Mn3O4、Mn3O4超细粉体、Mn3O4纳米带、纳米棒、纳米纤维、纳米空心球等。重点评述了近几年水热／溶剂热法制备纳米级Mn3O4新材料的研究进展，并展望了Mn3O4新材料制备技术的发展方向。     

溶剂(水)热模板法制备锂离子电池电极材料研究进展

形貌控制是改善锂离子电池电极材料性能的有效途径,溶剂(水)模板法是形貌控制的主要方法。溶剂(水)法易合成出分散且结晶良好的产物,控制合成条件可得到不同形貌产物,而模板法能控制并改进纳米微粒在结构材料中的排列、改善纳米材料性能。溶剂(水)热模板法兼有二者的优势,综述其在改善锂离子电池电极材料性能方面的发展现状及研究进展,总结该方法合成的锂离子电池电极材料的特点及目前可能存在的问题,并对该领域发展趋势进行展望。     

Cu(In,Al)(S,Se)_2薄膜的三靶共溅射制备与性能表征

采用磁控三靶共溅射的方法在玻璃衬底上沉积出了Cu-In-Al预制膜,后经硫硒化工艺得到了Cu(In,Al)(S,Se)2(CIASSe)薄膜吸收层,并利用XRD、EDAX、紫外-可见分光光度计等对薄膜样品结构、成分和光电性能进行了表征。研究了溅射功率、硫硒化温度及时间等工艺参数对CIASSe薄膜的结构、成分及光电性能的影响。结果表明:在CIA30W,Al60W,Cu50W三靶共溅的组合功率下,在540℃热处理,20 min后所得薄膜为贫铜的黄铜矿结构,晶体的晶化较好,晶粒沿着(112)晶向择优生长,薄膜成分接近理想的化学计量比,表面致密均匀,且其光学带隙约为1.40 eV,是性能较为良好的太阳能吸收层薄膜。     

半导体纳米材料Zn(en)3 Se,ZnSe及其光学性能研究

以有机溶剂热技术制备片状Zn（en）3Se（en为乙二胺）纳米材料,DTG、IR、XRD分析结果表明该化合物中乙二胺与中心离子Zn^2＋通过配位键相结合;以制得的纳米Zn（en）3Se为母体,在氮气氛中煅烧至980℃,热分解制得棒状纳米ZnSe;以TEM、ED初步研究了两者的形貌、结构;以提拉法分别将Zn（en）3Se、ZnSe纳米材料涂布在ITO导电玻璃上,制得纳米颗粒／ITO复合膜,并研究其光学特性。结果表明,Zn（en）3Se属立方晶系,呈片状结构;ZnSe属六方纤锌矿型,棒直径在40nm左右;可能的生长机理是乙二胺作为模板分子,首先嵌入到ZnSe无机结构框架中,接着受热分解逃逸出无机框架形成一维纳米棒。PL分析表明Zn（en）3Se的荧光红移至448nm处。     

纳米In2S3制备研究进展

硫化铟(In_2S_3)是一种重要的半导体材料,具有良好的导电性能、光学性能、声学性能及电子性能等,在纳米材料、微电子和太阳能领域有广阔的发展前景。In_2S_3纳米材料的制备方法主要有水热合成法、溶剂热合成法、喷雾热解法和超声法等,未来应注重开发低成本、高性能、环保绿色的合成方法。     

脉冲激光沉积法制备的Ge(S90Se10)2硫系薄膜中的光致漂白效应研究

运用激光脉冲沉积法（PLD）制备了Ge（S90Se10）2薄膜，通过运用紫外汞灯对制备的薄膜进行不同时间的辐照，我们确定了达到饱和状态所需要的辐照时间（90分钟）。当薄膜处于饱和状态时，巨大的光致漂白效应被观察到了（△E=0．36ev）。此外，在本文中，我们也对光致漂白效应的机理进行了阐述，一种新型的光电子材料被发现了。     

燃烧法制备氧化物纳米材料的研究进展

燃烧法是制备氧化物纳米材料的一种新方法，其中，气相燃烧法、燃烧火焰—化学气相凝聚法已经实现了工业化生产；而一些新的工艺方法，如低温燃烧合成法、喷雾燃烧法、电控火焰合成法在刺备纳米材料上也各有优缺点；燃烧法与其他技术的结合也在研究开发阶段。详细阐述了燃烧法的最新研究进展。     

机械球磨法制备纳米材料的研究进展

综述了机械球磨法制备纳米结构材料及其性能研究的最新研究进展。     

微波诱导燃烧法制备无机纳米材料的研究进展

近年来纳米材料的制备方法受到人们的广泛关注,出现了与之相关的大量专利文献报道.而微波诱导燃烧法制备纳米材料,操作简单易行、无需煅烧、所得产物粒径小、分布比较均匀.本文综述了微波诱导燃烧法的产生和发展,以及在制备一些简单纳米氧化物、纳米复合物、纳米金属及合金、无机纳米材料等几个方面的实际应用.最后展望了这一领域的应用和发展前景.     

Effects of different selenization conditions on the device parameters of CuIn(Se,S)2 solar cells

Parameter extraction can be used as a tool to determine the optimum chalcogenization condition of the absorber layer in manufacturing thin film solar cells. In this paper, CuIn(Se_1 − y,S_y)₂ solar cells fabricated at different selenization conditions using a two-step process were characterized. Device and performance parameters of the solar cells were determined from the current density-voltage (J-V) characteristics of the devices. The J-V curves were analyzed using the two-diode solar cell model. Devices selenized for 40-60 min exhibit relatively low series and shunt resistances, low fill factor and conversion efficiency. Better performance was observed for solar cells with absorber layer selenized for 10 to 20 min.     

Interfacial chemistry control in thin film solar cells based on electrodeposited CuIn(S,Se)2

In this work, we present a study on CuIn(S,Se)₂ absorbers prepared by electrodeposition followed by rapid thermal annealing promising to lower manufacturing cost. However the annealed material contains copper sulpho-selenide of Cu(S_y,Se_1 − y) type which is harmful for the electrical properties of photovoltaic devices. These phases are removed by a cyanide etching. Because of an intrinsic variability of absorber fabrication process, the presented survey is based on statistic approach. We highlighted the influence of a cyanide treatment on surface and bulk compositions. The surface composition follows a distribution according to a Cu(S,Se)-CuIn(S,Se)₂ system and the bulk composition agrees with Cu(S,Se)₂-CuIn₃(S,Se)₅ system. Moreover, surface composition can be modified by adjusting the cyanide concentrations of etching solution without any changes in the bulk one. It ensues that Cu(S,Se) is not only present on the surface but also in the bulk of samples.     

Electrical properties of chemically prepared nonstoichiometric CuIn(S,Se)2 thin films

Polycrystalline thin films of copper indium sulphoselenide [CuIn(S,Se)₂] were deposited on glass substrate by chemical bath deposition technique. The deposition parameters such as pH, temperature and time were optimized. A set of films having different elemental compositions was prepared by varying Cu/In ratio from 1·87–12·15. The films were characterized by X-ray diffraction (XRD) and energy dispersive X-ray analysis (EDAX). The chemical composition of the CuIn(S,Se)₂ was found to be nonstoichiometric. The d.c. conductivities of the films were studied below and near room temperature. The thermo-electric power of the films was also measured and type of semiconductivity was ascertained.     

Key role of Cu-Se binary phases in electrodeposited CuInSe2 precursors on final distribution of Cu-S phases in CuIn(S,Se)2 absorbers

Using micro-Raman spectroscopy, we demonstrate that the formation of the CuS binary phase in CISEL™ cells absorbers is highly determined by the presence of a Cu-Se binary phase in the precursors and depends on the Cu/In ratio. A selective sulphurization mechanism of the Cu-Se phase is proposed as the origin of CuS platelets. For low Cu/In ratio both binaries are associated to the surface and do not affect the device performance. Conversely, when the binary phase in the precursor is present close to the back contact (for high Cu/In ratio), the CuS binary phase is also formed at this region after sulphurization. Strongly associated to this Cu-rich binary phase, a spinel-type phase is also observed in the sulphurized samples. This phase has n-type conductivity, which has a strong impact on the characteristics of the solar cells. The relationship between the presence of these phases and the electrical properties of the final devices is described, showing that the reduction of the V_oc and the increase of the R_s are related to the formation of a back diode by the spinel-type layer, as consequence of an undesirable n-p-n structure.     

Electrodeposition based synthesis of S-rich CuIn(S,Se)2 layers for photovoltaic applications: Raman scattering analysis of electrodeposited CuInSe2 precursors

Single step electrodeposition (ED) of Se-rich CuInSe₂ precursors, followed by RTP annealing under sulphurising conditions leading to S-rich CuIn(S,Se)₂ films, constitutes a promising technology for low cost high efficiency solar cells. In this work, a Raman scattering (RS) analysis of Se rich precursors grown under ED conditions leading to different chemical compositions is reported. RS has allowed identification of the main secondary phases in these layers with elemental Se, Cu-Se binary and ordered vacancy compound (OVC) phases. The experimental data show a strong dependence of the spectral contributions related to Se and Cu-Se with the layer molecularity, and the formation of these phases is mainly determined by the content of excess Se in the layers. The correlation of these data with the characteristics of the solar cells fabricated with these precursors, shows the strong impact of the presence of the Cu-Se phase on the performance of the final devices. These results point out the key role played by this binary phase on the formation of secondary phases after the sulphurising step.     

Optical properties of Cu(In,Ga)Se2 and Cu2ZnSn(S,Se)4

The optical properties of CuInSe₂, CuGaSe₂, Cu₂ZnSnS₄, and Cu₂ZnSnSe₄ are investigated using three different first-principles methods, namely the generalized gradient approximation by Perdew, Burke, and Ernzerhof (PBE), the hybrid Hartree-Fock-like functional by Heyd, Scuseria, and Ernzerhof (HSE), and a Green's function approach (GW). The density-of-states, the complex dielectric function ε(ω) = ε₁(ω) + iε₂(ω), and the optical absorption coefficient α(ω) are determined, providing fundamental understanding of these materials. We find that even though the PBE method generates fairly accurate effective crystal potentials, the HSE and GW methods improve considerably the band-gap energies E_g and also the localization of the semicore states, thereby describing the optical properties much better. Furthermore, we also present optimized convergence parameters for the self-consistent HSE calculation in order to reduce the computational time of this orbital-dependent method.     

电化学沉积太阳电池用CuInSe2和Cu(In,Ga)Se2薄膜的研究进展

综述了电化学沉积太阳电池用CuInSe2(CIS)和Cu(In,Ga)Sez(CIGS)薄膜的研究和发展;对CIS和CIGS预制层的电化学沉积路线,包括一步沉积、分步沉积和特种电沉积的研究进展进行了详细的评述;综述了电沉积预制层的后处理,包括退火、化学处理和PVD调整成分的研究状况.回顾了基于电化学沉积的CIS和CIGS太阳电池研究的发展过程,并介绍了目前实验室和产业化研究的最新成果,指出了存在的问题并展望了其发展趋势.     

CuInSe2和Cu(In,Ga)Se2薄膜的制备进展

综述了CuInSe2 (CIS)和Cu(In,Ga)Se2 (CIGS)薄膜的最新制备和研究进展,重点论述了几种制备方法如热蒸发、喷涂热解、电化学沉积、溶解-旋涂、高温液相合成等对相应薄膜的形貌、结构、成分以及所组成太阳能电池光电性能的影响,探讨了这类薄膜太阳能电池存在的问题,展望了今后的研究方向.     

Comparative study of sputtered and electrodeposited CI(S,Se) and CIGSe thin films

Copper indium disulphide CuInS₂ (CIS) and diselenide CuInSe₂ (CISe) and their alloys with gallium CuIn_1 − xGa_xSe₂ (CIGSe) thin films have been prepared using both high- and non-vacuum processes. The well known two-stage process consisting in a sequential sputtering of Cu and In thin layers and a subsequent sulfurisation has led to the formation of good quality CuInS₂ ternary compound. The films exhibit the well known chalcopyrite structure with a preferential orientation in the (112) plane suitable for the production of the efficient solar cells. The absorption coefficient of the films is higher than 10⁴ cm^− 1 and the band gap value is about 1.43 eV. A non-vacuum technique was also used. It consists on a one step electrodeposition of Cu, In and Se and in a second time Cu, In, Se and Ga. From the morphological and structural point of view, the films obtained are similar to those prepared by the first technique. The band gap value increases up from 1 eV for the CIS films to 1.26 eV for the CuIn_1 − xGa_xSe₂ with 0 < x < 0.23. The resistivity at room temperature of the films was adjusted to 10 Ωcm after annealing. The films exhibit an absorption coefficient more than 10⁵ cm^− 1. The most important conclusion of this study is the interesting potential of electrodeposition as a promising option in low-cost CISe and CIGSe thin film based solar cells processing.