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  本文選題：鈣鈦礦太陽能電池　切入點：離子移動　出處：《北京交通大學》2017年碩士論文

【摘要】：有機-無機鈣鈦礦太陽能電池因為其低成本易制備高效率等特點,在過去的幾年中引起了廣泛關注,進一步提高其效率和穩(wěn)定性是研究工作者們都在進行的工作。通過對制備方法和處理方法的改進,目前關于鈣鈦礦太陽能電池的報道中提到其最高效率已超過22%,在測試過程中產(chǎn)生的電流-電壓回滯問題卻始終影響穩(wěn)定性。關于效率和穩(wěn)定性,本文中做了相關研究,具體分為兩個部分:1、首先我們對器件的制備方法進行了探索和研究。通過一步法和兩步法來制備鈣鈦礦晶體薄膜并進行比較,發(fā)現(xiàn)活性層的反應情況、結晶情況和表面形貌對器件的影響很大,經(jīng)過嘗試找到了能夠適合我們工作的高效率器件的制備方式;通過改變器件的空穴傳輸層和電子傳輸層等工作,發(fā)現(xiàn)合適電子/空穴傳輸層對于器件有促進作用,選定NiOx和PCBM作為空穴傳輸層和電子傳輸層。經(jīng)過各種優(yōu)化,將效率從開始的3%提高到了 15%。2、在對機理的探究中,我們發(fā)現(xiàn)不同形貌度的器件性能不同,表面粗糙器件往往伴隨著很大的電流-電壓回滯,表面光滑的器件只有很小的回滯,而這種電流-電壓回滯可以靠調(diào)節(jié)PCBM薄膜厚度來消除。據(jù)報道,回滯的產(chǎn)生是因為界面電荷的聚積,這種聚積引起了界面處的能帶彎曲,從而影響電荷的輸運和收集。有意思的是,表面粗糙的器件界面電荷的密度也很大。聯(lián)系這一切,我們提出了一種模型來解釋以上的現(xiàn)象:界面電荷的聚積和界面處的電容息息相關,電容越大,聚積的電荷越多。粗糙的表面造成較大的電容相對面積,同時,PCBM太薄會導致電容兩極板距離過近,這都是界面電容很大的原因,得到的實驗數(shù)據(jù)支持了這個結論。界面的電容可以靠更光滑的表面和厚度合適的PCBM層來減小,從而削弱界面電荷的聚積,借此來提高器件的效率同時減少電流-電壓回滯。
[Abstract]:Organic-inorganic perovskite solar cells have attracted much attention in the past few years because of their low cost and high efficiency.Through the improvement of the preparation method and the treatment method, the report on the perovskite solar cell mentioned that its maximum efficiency has exceeded 222.The current-voltage hysteresis problem has always affected the stability.As to the efficiency and stability, this thesis is divided into two parts: 1. Firstly, we study the fabrication methods of the devices.The perovskite crystal films were prepared by one-step method and two-step method and compared. It was found that the reaction of the active layer, the crystallization and the surface morphology had a great influence on the device.By changing the hole transport layer and electron transport layer of the device, we find that the appropriate electron / hole transport layer can promote the device.NiOx and PCBM are selected as hole transport layer and electron transport layer.After various optimizations, the efficiency was raised from 3% to 15.2. In the study of the mechanism, we found that the performance of the devices with different morphologies is different, and the surface roughness devices are often accompanied by large current-voltage hysteresis.The smooth surface of the device has only a small hysteresis, which can be eliminated by adjusting the thickness of the PCBM film.It is reported that hysteresis is caused by the accumulation of interfacial charges, which results in the bending of energy bands at the interface, which affects the transport and collection of charges.Interestingly, the surface roughness of the device interface charge density is also very large.In connection with all this, we propose a model to explain the above phenomena: the accumulation of interface charges is closely related to the capacitance at the interface, and the larger the capacitance, the more the accumulated charge.The large capacitance relative area caused by rough surface and too thin PCBM will lead to the close distance of the capacitor bipolar plate, which is the reason for the large interface capacitance. The experimental data support this conclusion.The capacitance of the interface can be reduced by a smoother surface and an appropriate thickness of PCBM layer, thus weakening the accumulation of the interface charge, thereby improving the efficiency of the device and reducing the current-voltage hysteresis.
【學位授予單位】：北京交通大學
【學位級別】：碩士
【學位授予年份】：2017
【分類號】：TM914.4

【參考文獻】

相關期刊論文 前1條

1 王福芝;譚占鰲;戴松元;李永舫;;平面異質結有機-無機雜化鈣鈦礦太陽電池研究進展[J];物理學報;2015年03期

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本文編號：1722158