介观太阳能电池对电极的制备及电池性能优化

发布时间：2018-02-27 20:02

本文关键词： 介观太阳能电池染料敏化太阳能电池对电极聚3 4乙烯二氧噻吩硫化镍碳材料碘铅甲胺钙钛矿　出处：《华中科技大学》2014年博士论文　论文类型：学位论文

【摘要】：介观太阳能电池(mesoscopic solar cell,MSC)是一种新型太阳能电池。它拥有一种独特的介孔结构,这种介孔结构使得这类电池相比其他类型太阳能电池而言,具有更大的表面积,从而有利于捕获更多的光子,产生较大的光电流。染料敏化纳米晶太阳能电池(Dye-sensitized solar cells,DSSC)是一类典型的介观太阳能电池。通常,它们采用纳米晶介孔二氧化钛(Ti02)半导体材料作为电子收集电极。这种基于纳米材料的介孔电极比表面积可高达285m2/g,是非介孔电极的780倍。迄今为止,基于此类介孔电极的介观太阳能电池器件最高光电转换效率已经超过15%。如此高的光电转换效率使得这类太阳能电池几乎可以与传统的硅基太阳能电池相媲美。不仅如此,介观太阳能电池相比于硅基太阳能电池而言,具有制备工艺更加简单、原料价格更加低廉、材料来源更加广泛等特点。这些特点都是新一代低成本清洁能源的必备要素,因此,介观太阳能电池在发展前景上具有比硅基太阳能电池更大的应用潜力。一般来说,DSSC按其电解质状态可分为两种：一种为液态DSSC;另一种为固态DSSC。其中,液态DSSC通常采用铂作为对电极,而固态DSSC通常采用金作为对电极。尽管DSSC的制备成本已经比硅基太阳能电池要低,但这种贵金属电极不管是从材料价格上来讲还是从制备工艺上来考虑,都在一定程度上阻碍了DSSC成本的进一步降低。而如果能找到一种更廉价的材料来替代其中的金属对电极,将会使DSSC成为一种真正意义上的低成本太阳能电池。本论文针对DSSC中贵金属电极所存在的材料成本高、制备工艺复杂等弊端,开发了一系列基于有机聚合物材料(聚3,4乙烯二氧噻吩,PEDOT)、无机化合物材料(硫化镍,NiS)以及碳材料(C)的对电极,并将这些电极应用在基于不同电解质的DSSC中。此外,通过对对电极的优化和对DSSC制备工艺的改良,获得了较为理想的器件效率。这类基于非贵金属电极材料电极的开发与应用,为今后低成本DSSC的发展提供了一种可行的思路。本论文的主要内容包括： (1)利用电聚合方法制备出了高催化性能的PEDOT电极。通过对聚合电量的调控,制备出了不同厚度的PEDOT对电极,并将其应用在基于碘体系电解质的DSSC中。电化学阻抗分析(EIS)及循环伏安(CV)测试结果表明,PEDOT电极聚合电量越多,其催化活性越好。经过对电池各部分的优化,采用200mC/cm2聚合电量条件下制备出的PEDOT200mc电极作为对电极,基于碘体系电解质的DSSC器件的光电转化效率可达7.60%,与同等条件下以Pt作为对电极的电池器件效率(7.87%)相当。 (2)以介孔无机氧化物Ti02做为支架结构,通过在氧化物孔道结构中聚合PEDOT制备出了一种新型PEDOT/TiO2复合电极,并将其应用在基于无机硫体系电解质的硫化镉(CdS)量子点敏化DSSC中。EIS结果表明,这种PEDOT/TiO2复合电极在无机硫电解质中具有比单纯PEDOT电极更高的催化活性。此外,采用电化学方法替代传统的连续离子层吸附反应法优化了CdS量子点的生长,并最终获得了光电转化效率达1.87%的CdS敏化DSSC。 (3)针对PEDOT电极可通过控制聚合电量的多少来调控电极的厚度,利用Bis-EDOT二聚体,降低PEDOT电极制备的聚合电压,制备出了均匀透明的PEDOT对电极,其透光度可高达90%以上。将此透明对电极应用于有机硫电解质(AT/BAT)中,组装出了一种新型双面DSSC。该双面DSSC的背面照射时光电转化效率为4.35%,达正面照射时光电转化效率的70%以上。 (4)采用一种新型脉冲电压沉积法制备出具有高催化活性的透明NiS对电极。扫描电子显微镜及电子能谱测试分析表明,通过不同脉冲周期的调控,不仅可以调控NiS对电极中NiS的颗粒大小,还可以控制其中Ni原子与S原子的比例。进一步的EIS、CV测试表明,S元素的增加能够提高NiS对电极在有机硫电解质(ET/BET)的催化活性。最终,组装出了基于此种透明NiS对电极的双面DSSC。该双面DSSC的背面照射时光电转化效率高达4.98%,达正面照射时光电转化效率的78%。 (5)在基于钙钛矿类吸光材料(碘铅甲胺,CH3NH3PbI3)的介观太阳能电池中,首次引入碳材料电极。采用一种碳单基板结构,成功制备出了CH3NH3Pbl3/TiO2异质结介观太阳能电池。通过对单基板膜厚的调控及对碳电极的优化,我们制备出了光电转化效率达6.64%的碳单基板电池器件。在此基础之上,采用片状Ti02纳米晶材料替代颗粒状Ti02纳米晶材料,进一步提升了器件效率。EIS分析表明,Ti02纳米片与CH3NH3PbI3之间的电子复合明显比Ti02纳米颗粒要小。最终,基于Ti02纳米片的电池器件光电转化效率达9.65%。
[Abstract]:Mesoscopic solar cell (mesoscopic solar cell, MSC) is a new type of solar cell. It has a unique mesoporous structure, the mesoporous structure makes this kind of battery compared to other types of solar cells, has a large surface area, so as to capture more light photons, produces a large current.
Dye-sensitized solar cells (Dye-sensitized solar cells, DSSC) is a kind of typical mesoscopic solar cells. Usually, they use nanocrystalline mesoporous titania (Ti02) semiconductor material as electron collecting electrode. The mesoporous electrodes based on nano material surface area can be as high as 285m2/g, which is 780 times of non mesoporous electrode so far, the mesoporous electrodes based on mesoscopic solar cell devices, the highest photoelectric conversion efficiency is more than 15%. so high photoelectric conversion efficiency makes this kind of solar cell can almost and silicon based traditional solar battery comparable. Not only that, compared to the mesoscopic solar cell silicon solar battery, is prepared the process is simpler, cheaper raw materials, source material more widely. These characteristics are the essential elements of a new generation of low cost clean energy, therefore, Mesoscopic solar cells have greater potential for application than silicon based solar cells in the future.
In general, DSSC according to the electrolyte state can be divided into two types: one is liquid DSSC; the other is the solid DSSC., liquid DSSC usually adopts platinum as the counter electrode, and the DSSC is usually used as the solid gold electrode. Although the DSSC preparation cost than silicon solar cells should be low, but this no matter from the noble metal electrode materials in terms of price or preparation from the system to consider, to some extent hindered the further reduction of the cost of DSSC. But if you can find a cheaper materials to replace the metal electrode, will make DSSC into a low cost solar cell in the true sense.
This paper based on the existing DSSC noble metal electrode materials of high cost, complicated preparation process defects, developed a series based on organic polymer (poly ethylene 3,4 two oxygen thiophene, PEDOT) material, inorganic compounds (nickel sulfide, NiS) and carbon materials (C) on the electrode, and the electrode application based on the different electrolyte DSSC. In addition, through the optimization of the electrode and the improvement of the preparation process of DSSC, get the ideal efficiency of the device. The development and application of non noble metal electrode material electrode based on, provides a feasible way for the future development of the low DSSC. The contents of this paper include:
(1) using electro polymerization prepared PEDOT electrode with high catalytic performance. Through regulating the polymerization charge, were prepared with different thickness of PEDOT electrode, and its application in the DSSC system based on iodine electrolyte. The electrochemical impedance analysis (EIS) and cyclic voltammetry (CV) test results the PEDOT electrode, the polymerization charge more, its catalytic activity is better. After optimization of each part of the battery, the PEDOT200mc electrode prepared by 200mC/cm2 polymerization charge conditions as the counter electrode, the photoelectric conversion efficiency of DSSC device system of the iodine electrolyte was 7.60% based on the battery efficiency of the device on the electrode as Pt and under the same conditions (7.87%).
(2) the mesoporous inorganic oxide Ti02 as a scaffold structure, through the polymerization of PEDOT in oxide pore structure prepared a new type of PEDOT/TiO2 composite electrode and its application in inorganic sulfur cadmium sulfide (CdS) electrolyte system based on quantum dot sensitized DSSC.EIS results show that the PEDOT/TiO2 composite electrode has a higher catalytic activity than PEDOT electrode in inorganic sulfur electrolyte. In addition, the successive ionic layer by electrochemical method to replace the traditional adsorption reaction was optimized by the growth of CdS QDs, and finally got the photoelectric conversion efficiency of 1.87% CdS sensitized DSSC.
(3) according to how much PEDOT electrodes can power by controlling the polymerization regulation of the electrode thickness, using two Bis-EDOT dimer, reducing the polymerization voltage of PEDOT electrode preparation, preparation of a uniform and transparent PEDOT on the electrode, the transmittance can reach more than 90%. The transparent electrodes for organic sulfur electrolyte (AT/BAT), assembled a conversion efficiency of 4.35% a new type of double sided DSSC DSSC. the time of back irradiation power, irradiation time of positive electric conversion efficiency of 70%.
(4) using a new type of pulse voltage deposition of transparent NiS with high catalytic activity of the electrode. Scanning electron microscopy and electron spectroscopy analysis shows that by controlling different pulse cycle, not only can control the NiS on the electrode in NiS particle size, but also can control the ratio of the Ni and S atoms EIS. Further, CV test shows that the increase of S element can improve the electrode of NiS in organic electrolyte sulfur (ET/BET) catalytic activity. In the end, the back of the transparent NiS assembled on the electrode of the double sided DSSC. DSSC based illumination when the photoelectric conversion efficiency is as high as 4.98%, up front irradiation time electricity conversion the efficiency of 78%.
(5) based on the perovskite type light absorbing material (iodine lead methylamine, CH3NH3PbI3) mesoscopic solar cell, first introduced carbon material electrode. Using a single carbon substrate structure, successfully prepared the CH3NH3Pbl3/TiO2 heterojunction solar cell. Through the regulation of the mesoscopic single substrate thickness and optimization of carbon electrode. We prepared carbon substrate of single battery device photoelectric conversion efficiency of 6.64%. On this basis, the shape of Ti02 nanocrystalline material instead of granular Ti02 nanocrystalline materials, to further enhance the efficiency of the device.EIS analysis showed that between Ti02 film and CH3NH3PbI3 composite nano electronic than Ti02 nanoparticles is smaller. In the end, the battery device the photoelectric conversion efficiency of Ti02 Nanopieces was based on 9.65%.

【学位授予单位】：华中科技大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TM914.4

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