Carbon Quantum Dots/TiOx Electron Transport Layer Boosts Efficiency of Planar Heterojunction Perovskite Solar Cells to 19%
Carbon Quantum Dots/TiOx Electron Transport Layer Boosts Efficiency of Planar Heterojunction Perovskite Solar Cells to 19%
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碳%20量子%20点/TiOx%20电子%20传输%20层%20Boosts%20效率%20of%20平面%20异质结%20钙钛矿%20太阳能%20电池%20至%2019%
DOI：
10.1021/acs.nanolett.6b05177
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发表时间：
2017-04-01
期刊：
影响因子：
10.8
通讯作者：
Yang, Yang
中科院分区：
文献类型：
--
作者：
Li, Hao;Shi, Weina;Yang, Yang
在平面n-i-p异质结钙钛矿太阳能电池中，电子传输层（ETL）在电荷提取和决定钙钛矿薄膜的形貌方面发挥着重要作用。在这里，我们报告了一种溶液处理的碳量子点（CQD）/TiO2 复合材料，它在可见光谱范围内的吸收可以忽略不计，这对于钙钛矿太阳能电池来说是一个非常有吸引力的特性。将这种新型 CQD/TiO2 ETL 与平面 n-i-p 异质结结合使用，我们在标准照明测试条件下实现了约 19% 的前所未有的效率。研究发现，与单独使用 TiO2 相比，CQD/TiO2 组合可提高开路电压和短路电流密度。各种先进的光谱表征，包括超快光谱、紫外光电子光谱和电子阻抗光谱，表明 CQ_D 增加了 CH3NH3PbI3-xClx 和 TiO2 ETL 界面之间的电子耦合以及有助于电子提取的能量杠杆。
In planar n-i-p heterojunction perovskite solar cells, the electron transport layer (ETL) plays important roles in charge extraction and determine the morphology of the perovskite film. Here, we report a solution-processed carbon quantum dots (CQDs)/TiO2 composite that has negligible absorption in the visible spectral range, a very attractive feature for perovskite solar cells. Using this novel CQDs/TiO2 ETL in conjunction with a planar n-i-p heterojunction, we achieved an unprecedented efficiency of similar to 19% under standard illumination test conditions. It was found that a CQDs/TiO2 combination increases both the open circuit voltage and short-circuits current density as compared to using TiO2 alone. Various advanced spectroscopic characterizations including ultrafast spectroscopy, ultraviolet photoelectron spectroscopy, and electronic impedance spectroscopy elucidate that the CQ_Ds increases the electronic coupling between the CH3NH3PbI3-xClx and TiO2 ETL interface as well as energy levers that contribute to electron extraction.