钙钛矿薄膜太阳能电池的掺杂研究

发布时间：2018-01-15 03:02

本文关键词：钙钛矿薄膜太阳能电池的掺杂研究　出处：《北京信息科技大学》2017年硕士论文　论文类型：学位论文

【摘要】：2009年以来,有机-无机卤化钙钛矿太阳能电池经历了飞跃式的发展,从最初的3.8%光电转换效率到目前的22.1%。钙钛矿材料的最大优点是它的吸光系数很大,并且有优良的双极性载流子输运性质。理想情况下,空穴传输层只能传输空穴,致密层只能传输电子。当有光照射到钙钛矿太阳能电池的光阳极时,钙钛矿层作为光吸收层吸收光子,钙钛矿被激发,产生电子空穴对,电子向致密层方向传输,空穴向空穴传输层方向传输。基于电子和空穴的传播方向的不同,分别在致密层/钙钛矿界面和空穴传输层/钙钛矿界面产生电子浓度梯度和空穴浓度梯度。这样,电子和空穴分别向致密层方向和空穴传输层方向扩散。然而,在钙钛矿层中电子和空穴向两个方向扩散过程中会发生一定程度的复合,导致了光生载流子的损失。如果将钙钛矿层做成p-n结或p-i-n结构,当太阳光照在p-n结或p-i-n结上时,会激发形成空穴-电子对(激子),在p-n结或p-i-n结电场的作用下,激子首先被分离成为电子与空穴并分别向阴极和阳极输运,光生空穴流向p区,光生电子流向n区,那么就会大大降低光生载流子在钙钛矿层中的复合,从而提高有机-无机卤化钙钛矿太阳能电池的光电转换效率,提高电池性能。Yanfa Yan课题组报道了利用钙钛矿外在掺杂性质的密度泛函理论计算,得出了有机无机钙钛矿太阳能电池材料掺杂的方法,结果是在一个非平衡的生长条件下可以制备出n型钙钛矿,掺杂实现n型钙钛矿是十分困难的;通过掺杂IA族,IB族或者VIA族元素,例如Na、K、Rb、Cu和O在I-rich生长条件下可以形成p型钙钛矿。本论文对钙钛矿薄膜进行p型掺杂。通过在PbI2和MAI前驱体溶液中掺杂不同浓度的KI、KI和不同浓度RbI共掺杂制备钙钛矿薄膜。使用一步法反溶剂滴加氯苯对不同浓度的KI、KI和不同浓度RbI共掺杂制备MAPbI3钙钛矿薄膜进行表征,薄膜的表征有表面SEM、横截面SEM、EDX、XRD测试;对它们制备得到的MAPbI3钙钛矿太阳能电池的表征有电流-电压测试(J-V测试)和IPCE测试。测试结果表明掺杂不同浓度的KI、KI和不同浓度RbI共掺杂不利于钙钛矿太阳能电池的光电转换效率。
[Abstract]:Since 2009, organic-inorganic perovskite solar cells have experienced a rapid development. From the initial 3.8% photoelectric conversion efficiency to the current 22.1.The biggest advantage of perovskite material is its large absorptivity and excellent bipolar carrier transport properties. The hole transport layer can only transfer holes and the dense layer can only transfer electrons. When light is irradiated to the photoanode of perovskite solar cells, the perovskite layer absorbs photons as the photoabsorption layer and the perovskite is excited. The generation of electron hole pairs, electron transport to the dense layer, hole transmission to the hole transport layer direction. Based on the different direction of electron and hole propagation. Electron concentration gradient and hole concentration gradient are produced at the dense layer / perovskite interface and hole transport layer / perovskite interface respectively. During the diffusion of electrons and holes in perovskite layer, a certain degree of recombination will occur, which leads to the loss of photogenerated carriers. If the perovskite layer is formed into p-n junction or p-i-n structure. When the sun illuminates on p-n or p-i-n junctions, a cavity-electron pair is generated (exciton, under the action of an electric field in p-n or p-i-n junctions). Excitons are first separated into electrons and holes and transported to cathode and anode respectively. Photogenerated holes flow to p region and photogenerated electrons flow to n region, so the photo-generated carrier recombination in perovskite layer will be greatly reduced. In order to improve the photoelectric conversion efficiency of organic-inorganic perovskite solar cells and improve the performance of the cell. Yanfa Yan team reported the density functional theory (DFT) calculation using perovskite external doping properties. The method of doping organic and inorganic perovskite solar cells is obtained. The results show that n-type perovskite can be prepared under a non-equilibrium growth condition, and it is very difficult to achieve n-type perovskite doping. By doping elements of IA group, IB group or VIA group, for example, Nahl Ko Rb. P-type perovskite can be formed by Cu and O under the condition of I-rich growth. In this paper, p-type perovskite films were doped with different concentrations of Ki in the solution of PbI2 and MAI precursors. Perovskite thin films were prepared by co-doping Ki with different concentrations of RbI. One step antisolvent was used to add chlorobenzene to different concentrations of Ki. MAPbI3 perovskite thin films were prepared by Ki and different concentrations of RbI co-doped. The MAPbI3 perovskite solar cells were characterized by current-voltage test (J-V test) and IPCE test. The co-doping of Ki and RbI is unfavorable to the photovoltaic conversion efficiency of perovskite solar cells.
【学位授予单位】：北京信息科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM914.42

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