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91.
This paper is concerned with the improvement of dye-sensitized solar cell (DSSC) efficiency upon MgO post-treatment of the TiO2 electrode. A simple sol–gel technique, involving magnesium acetate as precursor, ethanol as solvent and nitric acid as stabilizer, is applied to prepare a solution of suspended MgO nanoparticles. A single drop of MgO sol at 0.1 M precursor concentration was spin-coated at 3000 rpm for 30 s onto the TiO2 electrode and sintered at 500 K for 1 h. Dye-loading using N3-dye was applied for 6 h. An increase in the average efficiency of the DSSC from 2.5% to 3.9% (over 50% enhancement) was recorded. Measurements of the dark I–V characteristics, the open circuit voltage decays, the SEM images and the dye absorbance spectra, for both uncoated and MgO-coated electrodes were examined. The improvement of the DSSC efficiency was attributed to an upward shift of the TiO2 flat band energy and a reduction of the rate of back-transport and recombination. 相似文献
92.
A semiconducting single-walled carbon nanotubes (s-SWCNTs) interlayer between poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) and n-Si was used for high performance organic-Si hybrid photovoltaic (PV) devices. The s-SWCNTs films with different thickness were utilized to investigate the PV effect on PEDOT:PSS/Si device performance. The surface potential of Si substrate with s-SWCNTs was dramatically reduced, which increased the compatibility between Si and PEDOT:PSS. In addition, s-SWCNTs with good semiconducting properties, guaranteed the charge transfer between Si and PEDOT:PSS. Therein, the electrical contact was dramatically improved with addition of s-SWCNTs interlayer, which led to increased fill factor. A power conversion efficiency (PCE) of 12.14% was achieved with an optimized thickness of s-SWCNTs layer. The s-SWCNTs interface layer was fabricated by a simple solution processed method, which was easily coupled with organic-Si solar cells to enhance the PCE. 相似文献
93.
94.
In the case of N-type solar cells,the anti-reflection property,as one of the important factors to further improve the energy-conversion efficiency,has been optimized using a stacked Al2O3/SiNx layer.The effect of SiNx layer thickness on the surface reflection property was systematically studied in terms of both experimental and theoretical measurement.In the stacked Al2O3/SiNx layers,results demonstrated that the surface reflection property can be effectively optimized by adding a SiNx layer,leading to the improvement in the final photovoltaic characteristic of the N-type solar cells. 相似文献
95.
ZHENG Jian-bang REN Ju HOU Chao-qi 《半导体光子学与技术》2005,11(4):248-252,258
Using the electrochemical polymerization dye sensitization (ECDS) method, polyaniline (PAn), which is used as top region material in solar cells, is sensitized with direct blue dye(DS), and sensitized Al grid/DS-PAn/n-Si/Al heterojunction solar cells is prepared by ECDS. Influences of the ECDS on the absorption spectrum and the junction characteristics of the solar cell were discussed, and the output characteristics were measured. The results show that the absorption spectrum of the sensitized PAn films is much wider and stronger in Vis-range; the diode quality factor is about 6.3 and the height of latent barrier potential of p-n junction is 0.89 eV; the short-circuit current and the conversion efficiency of sensitized DS- PAn/Si heterojunction solar cells are greatly improved, which the short-circuit current can increase 6 times, the fill factor is 57% and the efficiency can reach 1.42 % under the illumination of 37.2 W/m^2 , respectively. 相似文献
96.
Holger Rhm Tobias Leonhard Michael J. Hoffmann Alexander Colsmann 《Advanced functional materials》2020,30(5)
Seemingly contradictory reports on polar domains and their origin have surrounded the controversial discussion about the ferroelectricity of the methyl ammonium lead iodide (MAPbI3) thin films that are commonly employed in perovskite solar cells. In this work, microscopic modulations of the polar domain patterns upon application of an electric poling field are correlated with macroscopic changes to the currents through the MAPbI3 layer. Piezoresponse force microscopy is used to monitor the widening, narrowing, generation or extinction of polar domains, as well as shifts of the domain walls at room temperature under an in‐plane electric poling field that is applied between two laterally organized electrodes. This poling leads to a net polarization of individual grains and the thin film itself. Macroscopically, this net polarization results in a persistent shift of the diode characteristics that is measured across the channel between the electrodes. Both the modulation of the polar domains upon electric poling and the concurrent persistent shift of the electric currents through the device are the unambiguous hallmarks of ferroelectricity, which demonstrate that MAPbI3 is a ferroelectric semiconductor. 相似文献
97.
为了解决太阳能工程项目中光伏效率不高的问题,设计了双轴太阳能跟踪装置,该系统采用视日轨迹跟踪方案。文中着重分析了双轴跟踪的原理及其系统组成,利用光伏元件和STC89C52单片机实现大范围太阳跟踪,液晶显示屏实时显示最佳接收方位角及温湿度。在光线充足的天气条件下,跟踪装置自动旋转并始终保持太阳光垂直照射在太阳能电池的表面。在阴雨天或夜间等光线不足的条件下系统停止跟踪太阳转动。整个系统不需要任何外部电源供电,实现对太阳的高精度跟踪,并且使系统具有较强的抗干扰和运算能力。 相似文献
98.
Filip Duerinckx Kris Van Nieuwenhuysen Hyonju Kim Izabela Kuzma‐Filipek Harold Dekkers Guy Beaucarne Jef Poortmans 《Progress in Photovoltaics: Research and Applications》2005,13(8):673-690
Thin‐film epitaxial silicon solar cells are an attractive future alternative for bulk silicon solar cells incorporating many of the process advantages of the latter, but on a potentially cheap substrate. Several challenges have to be tackled before this potential can be successfully exploited on a large scale. This paper describes the points of interest and how IMEC aims to solve them. It presents a new step forward towards our final objective: the development of an industrial cell process based on screen‐printing for > 15% efficient epitaxial silicon solar cells on a low‐cost substrate. Included in the discussion are the substrates onto which the epitaxial deposition is done and how work is progressing in several research institutes and universities on the topic of a high‐throughput epitaxial reactor. The industrial screen‐printing process sequence developed at IMEC for these epitaxial silicon solar cells is presented, with emphasis on plasma texturing and improvement of the quality of the epitaxial layer. Efficiencies between 12 and 13% are presented for large‐area (98 cm2) epitaxial layers on highly doped UMG‐Si, off‐spec and reclaim material. Finally, the need for an internal reflection scheme is explained. A realistically achievable internal reflection at the epi/substrate interface of 70% will result in a calculated increase of 3 mA/cm2 in short‐circuit current. An interfacial stack of porous silicon layers (Bragg reflectors) is chosen as a promising candidate and the challenges facing its incorporation between the epitaxial layer and the substrate are presented. Experimental work on this topic is reported and concentrates on the extraction of the internal reflection at the epi/substrate interface from reflectance measurements. Initial results show an internal reflectance between 30 and 60% with a four‐layer porous silicon stack. Resistance measurements for majority carrier flow through these porous silicon stacks are also included and show that no resistance increase is measurable for stacks up to four layers. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
99.
以太阳能路灯系统为例,提出优化方法.主要从能耗的降低、性能的稳定以及系统成本的减少人手,计算太阳能光伏组件和蓄电池容量,确定太阳能路灯系统优化配置的方法.同时系统实行智能控制,在保护蓄电池使用寿命的前提下,保证最大正常工作时间,从而提高太阳能路灯的节能性和经济性. 相似文献
100.
采用热注入法制备了Cu2ZnSnS4(CZTS)纳米颗粒,并形成高分散、稳定的"墨水",采用滴注方法形成CZTS前驱体薄膜。利用X射线衍射(XRD)、拉曼光谱(Raman)、透射电子显微镜(TEM)和紫外-可见光谱(UV-VIS)对CZTS纳米颗粒的晶体结构、表面形貌和带隙进行了表征。Raman数据显示合成的纳米颗粒为纯的CZTS,不存在ZnS和Cu2SnS3等杂相。傅里叶红外光谱(FTIR)和UV-VIS表明合成的CZTS纳米颗粒表面被油胺(OLA)包覆,并且其带隙为1.52 eV。对CZTS前驱体薄膜在硫化氢气氛和固态硒气氛中退火处理,得到铜锌锡硫硒(CZTSSe)薄膜。结果表明,经硫化氢处理后薄膜表面平整但CZTS晶粒并没长大,而经过固态硒处理后得到了结晶质量较好的CZTSSe薄膜。 相似文献