带有缓变层的大面积集成型a—Si：H太阳电池的研制

报道了把缓变层用于大面积（２７９０ｃｍ＾２）单结集成型ａ－Ｓｉ：Ｈ太阳电池板工业化生产的研究工作。分析了它对太阳电池板性能参数Ｖｏｃ，Ｉｓｃ、ＦＦ、η的影响和对提高ａ－Ｓｉ：Ｈ太阳电池板转换效率的作用。试验所得电池板的平均开路电压达２５．１Ｖ，平均转换效率达６．２％，分别比同时生产的无缓变层电池板的水平提高９．１３％和１６．９８％。试验中最好的电池板开路电压达２５．６Ｖ，转换效率达６．６％。     

大面积集成型a－SiC：H／a－Si：H叠层太阳电池的研制

报道了大面积（２７９０ｃｍ２）集成型ａ－ＳｉＣ：Ｈ／ａ－Ｓｉ：Ｈ叠层太阳电池的研制及稳定性实验结果，讨论了限制该电池效率的一些因素。实验电池的性能参数：Ｖｏｃ＝４０．８Ｖ，ＩＳＣ＝５３０．４０ｍＡ，ＦＦ＝４９．４％，有效面积（２２８０ｃｍ２）光电转换效率ＥＦ＝４．６９％（ＡＭ１．５，１００ｍＷｃｍ－２，２５℃）。制备出光电子学性能优良的ａ－ＳｉＣ：Ｈ薄膜及解决电池内部ｎ／Ｐ结的接触问题是提高该电池性能的关键。     

p／i界面的缓变层对大面积（2790cm^2）a—Si：H太阳电池性能影响的研究

报道了在大面积（２７９０ｃｍ２）ｐ－ｉ－ｎ型ａ－Ｓｉ∶Ｈ异质结太阳电池ｐ／ｉ界面之间引入缓变层（ＣＧＬ∶Ｃ，ＣＧＬ∶Ｂ∶Ｃ）对电池性能影响的研究结果。实验发现，带有ＣＧＬ∶Ｃ的ａ－Ｓｉ∶Ｈ太阳电池性能的改善主要来源于开路电压的提高，带有ＣＧＬ∶Ｂ∶Ｃ的ａ－Ｓｉ∶Ｈ太阳电池性能的提高主要来源于填充因子ＦＦ的增加。提出了带有缓变层ａ－Ｓｉ∶Ｈ电池的能带模型，据此分析了ｐ／ｉ结附近载流子的复合动力学过程，从理论上解释了实验中所发现的现象。     

400cm2 a-Si/a-Si叠层太阳电池的研究

以全部国产化装备和工业用原材料，以简单铝背电极制备出初始效率为８．２８％，经室外阳光照射一年后稳定效率为７．３５％，面积为２０ｃｍ×２０ｃｍ，有效面积为３６０ｃｍ２ａ－Ｓｉ／ａ－Ｓｉ叠层太阳电池。主要制备技术措施：（１）ＴＣＯ／ｐ界面接触特性的改善；（２）μｃ－ＳｉＣ∶Ｈ／ａ－ＳｉＣ∶Ｈ复合窗口层技术；（３）ｐ／ｉ界面Ｈ处理；（４）高质量本征ａ－Ｓｉ∶Ｈ材料；（５）优良的ｎ１／ｐ２隧道结；（６）最佳电池结构设计等。     

高效非晶硅叠层太阳电池的优化设计

研究了高效ａ－Ｓｉ／ａ－Ｓｉ／ａ－Ｓｉ－ＳｉＧｅ三结太阳电池的优化设计。电流匹配是影响二端子叠层太阳电池填充因子的关键因素，在内电极的ｐ／ｎ界面外附加载流子复合是由少数载流子浓度、界面态和ｐ／ｎ界面处材料的几何因素匹配决定的。利用适当的带隙匹配和ｉ层厚度匹配来实现ａ－Ｓｉ／ａ－Ｓｉ／ａ－ＳｉＧｅ三结太阳电池结构的最佳化，同时采用改善ｎ／ｉ界面特性的缓冲层技术，获得了Ｖｏｃ＝２．４８Ｖ，Ｊｓｃ＝６．     

SnO_2／p接触特性对a－Si太阳电池填充因子的影响

用ＰＥＣＶＤ方法制备出高电导率（～０．２ｓｃｍ－１）、宽带隙（～２．２ｅＶ）的Ｐ型微晶化硅碳合金（ｐ－μｃ－ＳｉＣ：Ｈ）薄膜材料。利用ｐ－μＣ－ＳｉＣ：Ｈ／ｐ－ａ－Ｓｉ：Ｈ复合结构做ａ－Ｓｉ太阳电池的窗口材料，明显改善了ＳｎＯ２／ｐ之间的接触特性，从而使１０ｃｍ×１０ｃｍ单结集成型电池的填充因子从０．７０以下提高到０．７２。     

快速汽相沉积法制备硅薄膜太阳电池

对在重掺杂抛光单晶硅衬底上用ＲＴＣＶＤ法形成硅薄膜太阳电池进行了研究。衬底为〈１００〉晶向ｐ＋ ＋ 型重掺硅片,电阻率为５×１０－ ３Ωｃｍ 。主要工艺过程为：在衬底上生长一层硅薄膜同时掺硼,膜厚３８μｍ ,扩磷制备ｐ－ｎ 结,背面蒸Ａｌ及Ｔｉ／Ｐｄ／Ａｇ 制背电极,正表面在扩散后生长一层ＳｉＯ２ ,前面用光刻剥离法制备Ｔｉ／Ｐｄ／Ａｇ 电极,制成的１ｃｍ ２ 太阳电池,开路电压ＶＯＣ＝ ６１２．８ｍ Ｖ,短路电流ＩＳＣ＝ ２９．３ｍ Ａ,填充因子ＦＦ＝ ０．７５７９,效率η＝ １３．６１。对一些影响电池特性的因素进行了研究,发现硅薄膜的掺杂浓度、发射层的掺杂浓度以及减反射层都对太阳电池的特性有较大影响。     

大面积单结a—Si：H太阳电池方阵现场稳定性的评价与测试方法

对不同工作状态的２７８７ｃｍ＾２单结集成型ａ－Ｓｉ：Ｈ太阳电池组件室外１年多的实验结果与２ｋＷａ－Ｓｉ：Ｈ太阳电池方阵现场运行４年多的结果进行比较，说明组件或方阵在室外运行１年后，经过正常衰退阶段，其性能趋于稳定。同时给出了大功率ａ－Ｓｉ：Ｈ太阳电池方阵性能的现场测试方法。     

CdS／CdTe－CdS／Cu_2S异质二重结薄膜太阳电池的设计与计算

根据半导体材料的性能参数，考虑光电压Ｖ和耗尽区宽度Ｗ的变化对光电流ＪＬ的影响，较严格地计算了ＣｄＳ／ＣｄＴｅ和ＣｄＳ／Ｃｕ２Ｓ两种异质结单晶薄膜太阳电池的光伏特性曲线。然后在的条件下，对由上述两种异质结构成的二重结太阳电池的ＣｄＴｅ、Ｃｕ２Ｓ厚度进行匹配，计算各种组合下二重结太阳电池的光伏特性曲线。理论证明最佳匹配厚度Ｈｍａｘ约为９．０６μｍ，最大短路电流、开路电压、转换效率分别为１４．２２ｍＡｃｍ－２、１．３Ｖ和１４、６８％。     

AlxGa1—xAs／GaAs太阳电池减反射膜的研究

以太阳电池的短路电流积分表达式为依据，应用减反射膜的光学原理，对具有阳极氧化、ＳｉＯ和ＳｉＯ２三种减反射膜的ＡｌｘＧａ１－２Ａｓ／ＧａＡｓ太阳电池分别进行了反射光谱、短路电流、开路电压的实验测试。研究表明，阳极氧化膜、ＳｉＯ膜具有良好的减反射性能，而ＳｉＯ２膜的减反射性能较差。     

Non-concentrating and asymmetric compound parabolic concentrating building façade integrated photovoltaics: An experimental comparison

Concentration of solar energy increases the illuminated flux on the photovoltaic (PV) surface thus less PV material is required. A novel asymmetric compound parabolic photovoltaic concentrator has been characterised experimentally with a similar non-concentrating system. Different numbers of PV strings connected within the system have been analysed and a power ratio of 1.62 measured compared to a similar non-concentrating PV panel with the same cell area. The solar to electrical conversion efficiency of 8.6% and 6.8% was achieved for the non-concentrating panel the concentrating system, respectively. The measured average solar cell temperature of the PV in the concentrator system was only 12 °C higher than that of the similar non-concentrating system with same cell area.     

RF PLANAR MAGNETRON SPUTTERING OF POLYCRYSTALLINE CdTe THIN-FILM SOLAR CELLS

Polycrystalline CdTe thin films have been prepared (using radio frequency (rf) planar magnetron sputtering), characterized, and used to fabricate CdS/CdTe solar cells. The performance characteristics of the best device (as measured under standard reporting conditions) are a conversion efficiency of 8.2% and 0.68 V and 21.7mA/cm2 for open-circuit voltage (Voc) and short-circuit: current density (J), respectively. Photoluminescence emission from the polycrystalline CdTe films (after the high-temperature heat treatment) showed that this material is dominated by four defects, including two donor levels Dl and D2 (at 120 and 180 meV below the conduction band) and two acceptor levels Al and A2 (at 30 and 65 meV above the valence band [VB]). Capacitance-voltage (C-V) measurements have indicated the formation of an n-i-p structure dominated by a high density of interface states. Deep level transient spectroscopy (DLTS) data also confirmed a minority electron trap at about 1.212 meV below the conduction band (CB) dominating the CdTe device. The trap level detected in a Schottky barrier, fabricated on a CdTe film without heating at high temperature, is deeper and higher in density than that in the heterojunction. This explains the enhancement of the Voc of the heterojunction devices after annealing at 400°C or higher. Although the device performance is modest by comparison with state-of-the-art devices, these results support the potential of sputter depositing CdTe films as a production technique. Considerable work must still be done to improve the material quality and reduce the density of defect levels.     

Amine functionalized homoleptic ruthenium(II) sensitizer for dye-sensitized solar cells: A combined effect of ancillary ligands and co-sensitization

In this work, we propose a homoleptic ruthenium(II) complex, [Ru(dabpy)₃]Cl₂ (RDAB3) containing amine functionalized electron donating anchoring units for DSSCs. The DSSCs were co-sensitized by coumarin-based thiophene (CT) and indole (CI) units. The presence of four ancillary amine groups in RDAB3 influences its photovoltaic performance and the introduction of coumarin-based co-sensitizers significantly enhances the efficiency. The fabricated DSSCs were explored by UV-Visible absorption, photocurrent-voltage assessments, and impedance spectral studies. Co-sensitized DSSCs showed an improved photovoltaic efficiency than the device sensitized by RDAB3 alone. Under optimized condition, the device made up of RDAB3+CI exhibited a high Jsc = 9.9 mA/cm² with Voc of 0.7 V, fill factor of 0.773, and solar to power conversion efficiency of 5.35% in standard global AM 1.5 solar irradiation. This performance is found to be higher than the DSSC sensitized with RDAB3 (η = 3.84%) fabricated under same circumstances.     

Twenty-two percent efficiency HIT solar cell

We have achieved the world's highest solar cell conversion efficiency of 22.3% (V_oc: 0.725 V, I_sc: 3.909 A, FF: 0.791, total area: 100.5 cm², confirmed by AIST) by using a heterojunction with intrinsic thin layer (HIT) structure. This is the world's first practical-size (>100 cm²) silicon solar cell that exceeds a conversion efficiency of 22% as a confirmed value. This high efficiency has been achieved mainly due to improvements in a-Si:H/c-Si hetero-interface properties and optical confinement.The excellent a-Si:H/c-Si hetero-interface of the HIT structure enables a high V_oc of over 0.720 V and results in better temperature properties. In order to reduce the power-generating cost, we are now investigating numerous technologies to further improve the conversion efficiency, especially the V_oc, of HIT solar cells, with the aim of achieving 23% efficiency in the laboratory by 2010.     

New proposal for photovoltaic-thermal solar energy utilization method

One of the most effective methods of utilizing solar energy is to use the sunlight and solar thermal energy such as a photovoltaic-thermal panel (PV/T panel) simultaneously. From such a viewpoint, systems using various kinds of PV panels were constructed in the world. In these panels, solar cells are set up at an absorber collecting solar thermal energy. Therefore, temperature of solar cell increases up to the prescribed temperature of thermal energy use, although it is lower than the cell temperature when using only solar cell panel. For maintaining cell conversion efficiency at the standard conditions, it is necessary to keep the cell at lower temperature. In this paper, electric and thermal energy obtained from a PV/T panel is evaluated in terms of energy. Based on this evaluation, the method of not to decrease cell conversion efficiency with collecting solar thermal energy was proposed.     

Improved model for solar cells with up-conversion of low-energy photons

In this paper we analyze the system proposed by Trupke T, Green MA, Würfel P. [Improving solar cell efficiencies by up-conversion of sub-band-gap light. J Appl Phys 2002; 92: 4117–22] to increase solar cells efficiency. The system consists in adding to the cell a so-called up-converter, which is a device able to convert the low-energy (sub-band gap) incident solar photons into photons of higher energy. The main novelty of the present model consists in taking into account appropriately the refractive index of solar cell and converter materials. Two configurations are studied: cell and rear converter (C–RC) and front converter and cell (FC–C), respectively. The main conclusions of this work are as follows: (1) The maximum solar energy conversion efficiency increases in case of the C–RC system as compared to the efficiency of a solar cell operating alone, especially at higher values of the concentration ratio; (2) the solar energy conversion efficiency of the C–RC system increases by increasing both the cell and the up-converter refractive indices; (3) the energy conversion efficiency does not increase by adding a front up-converter to the cell, whatever the value of the concentration ratio is.     

Fabrication of amorphous silicon p-i-n solar cells using ion shower doping technique

We have studied the fabrication of amorphous silicon (a-Si : H) p-i-n solar cells using an ion shower doped n⁺-layer. The p-i-n cells with ion-doped n⁺-layer exhibited open-circuit voltage of > 0.8 V, fill factor of > 0.62 and conversion efficiency of > 8.4% when the ion acceleration voltage was between 3 and 7 kV. The a-Si : H p-i-n solar cell fabricated under an optimized ion-doping condition exhibited an open-circuit voltage of 0.84 V, a fill factor of 0.66 and a conversion efficiency of 9.9% which was very similar to those of conventional a-Si : H p-i-n cells fabricated in the same deposition chamber. Therefore, ion shower doping technique can be applied to fabricate large area, high performance a-Si : H p-i-n solar cells.     

Design and Optimization of Amorphous Based on Highly Efficient HIT Solar Cell

The objective of this paper is to improve the power conversion efficiency of HIT solar cell using amorphous materials. A high efficiency amorphous material based on two dimensional heterojunction solar cell with thin intrinsic layer is designed and simulated at the research level using Synopsys/RSOFT-Solar Cell utility. The HIT structure composed of TCO/a-Si:H(p)/a-Si:H(i)/c-Si(n)/a-Si:H(i)/a-Si:H(n⁺)/Ag is created by using of RSOFT CAD. Optical characterization of the cell is performed by Diffract MOD model based on RCWA (rigorous coupled wave analysis) algorithm. Electrical characterization of the cell is done by Solar cell utility using based on Ideal diode method. In addition, optimization of the different layer thickness in the HIT structure is executed to improve the absorption and thereby the photocurrent density. The proposed HIT solar cell structure resulted in an open circuit voltage of 0.751 V, a short circuit current density of 36.37 mA/cm² and fill factor of 85.37% contributing to the total power conversion efficiency of 25.91% under AM1.5G. Simulation results showed that the power conversion efficiency is improved by 1.21% as compared to the reference HIT solar cell. This improvement in high efficiency is due to reduction of resistive losses, recombination losses at the hetero junction interface between intrinsic a-Si and c-Si, and optimization of the thicknesses in a-Si and c-Si layers.     

电聚合PANI作为低成本离子液体型DSSC对电极

用原位电聚合的方法在FTO导电玻璃上制备出了SO42-杂化的聚苯胺(PANI)(厚度10μm),并用循环伏安表征了其电聚合过程。通过扫描电镜表征,这种聚苯胺具有粗糙多孔的结构,有利于形成高比表面积的对电极。制备了以PMII和[EMIm]BF4、[EMIm]NTf2、[EMIm]N(CN)2不同组成比例的二元离子液体作为电解液的染料敏化太阳电池(DSSC)并研究其光伏行为,发现:使用[EMIm]N(CN)2和PMII(4∶6)电解液能得到最佳光电参数:短路电流密度Jsc(10.4mA.cm-2),开路电压Voc(0.655V),填充因子FF(0.521)和光电转换效率η(3.56%)。通过研究3种电解液的电导率I,3-和I-离子扩散系数,发现[EMIm]N(CN)2和PMII(4∶6)电解液具有最高的电导率和离子扩散系数。     

硅纳米线阵列太阳电池的性能分析

采用金属催化腐蚀法分别在(100)和(111)硅片表面制备出大面积垂直排列和倾斜排列的单晶硅纳米线阵列,垂直阵列在300～1000nm波段的平均反射率约为2.5%,倾斜阵列在该波段的平均反射率约为5%。基于垂直阵列和倾斜阵列制作的硅纳米线阵列太阳电池的最高转换效率分别为9.31%和11.37%。倾斜阵列电池的串联电阻比垂直阵列电池有所减小,使电池填充因子增大,性能有所提升。载流子复合是硅纳米线阵列太阳电池中电学损失的主导,使电池性能明显低于常规单晶硅电池。