面向钙钛矿太阳能电池应用的叶脉分形网络透明电极的电荷输运性能及其机理研究

Transparent conductive electrodes (TCEs) are the key components of solar cells, which determines the overall efficiencies of corresponding devices, thus the researches of TCEs and their transport behavior have been the cutting-edge topic of the field. Based on our preliminary researches in new metal network transparent electrodes, we will further manipulate the microstructure and optoelectronic properties of network electrodes; explore the mechanism of the influence of network structures, especially the leaf-vein fractal structure on the electrode charge transport behavior. The main work will be done including: (1) Preparation and manipulation of leaf-vein fractal TCEs and characterization of microstructure of TCEs; (2) Characterization of optoelectronic and mechanical properties of TCEs and their relationship with structure features (characteristic size, shape, features, etc.); (3) Design and fabrication of flexible film perovskite solar cells with as-made TCEs, I-V characterizations, and the mechanism of charge transport behavior of leaf-vein fractal TCEs in the cell devices; ⑷ Analytical derivation and simulation of charge transport behavior of leaf-vein fractal network electrodes. The project intents to obtain high-quality transparent electrodes, and corresponding high-efficiency flexible solar cells, especially to clarify the mechanism of charge transport behavior of leaf-vein fractal electrodes. Our work will provide useful theoretical and experimental results for new type transparent electrode design, performance manipulation, and its application in photovoltaic cells, etc.

透明电极是光伏器件的关键部件，其光电性能对器件的效率具有决定性作用。透明电极的光电子输运行为的研究也是该领域的前沿课题。本项目基于申请人前期在金属网格透明电极的研究基础上，拟对金属网络电极微结构和光电性能进行调控，并探索研究各种网络结构，特别是叶脉分形网络结构对电极电荷收集和输运行为的影响机制。内容包括：(1)叶脉分形结构电极的制备、微结构表征；(2)透明电极结构特征(尺寸特征和形状特征)对电极光电性能、机械性能的影响作用及其工艺调控；(3)基于叶脉分形结构电极柔性薄膜钙钛矿电池器件的构建和IV性能测试，并实验研究叶脉分形结构电极在电池器件中的电荷输运行为；⑷叶脉分形网络结构电极电荷输运行为的解析式推导及其理论模拟。本项目将获得新型透明电极，及其高效率柔性钙钛矿光伏电池，揭示叶脉分形网络电极高效电荷输运机制，为新型透明电极的设计、及其在光伏电池中的应用提供有益的实验结果和理论指导。

本项目围绕金属网格透明电极的基础和应用基础研究，对金属网络电极微结构和光电性能进行了调控，并深入研究了各种网络结构，特别是叶脉分形网络结构对电极电荷收集和输运行为的影响机制。我们主要完成了以下内容：(1)基于叶脉分形结构电极的制备、微结构表征；(2)透明电极结构特征(尺寸特征和形状特征)对电极光电性能、机械性能的影响作用及其工艺调控；(3)基于叶脉分形结构电极柔性薄膜钙钛矿电池器件的构建和性能测试，并实验研究了叶脉分形结构电极在电池器件中的电荷输运行为；⑷完成了叶脉分形网络结构电极电荷输运行为的解析式推导及其理论模拟。本项目除了完成既定任务，也开展了与柔性钙钛矿电池相关的一系列研究，例如电子输运层、空穴输运层的制备、钙钛矿活性层缺陷态的调控、以及柔性器件的转移方法等。总之本项目获得了新型透明电极，及其高效率柔性钙钛矿光伏电池，揭示叶脉分形网络电极高效电荷输运机制，为新型透明电极的设计、及其在光伏电池中的应用提供有益的实验结果和理论指导。四年来，基于此项目，包括在Nature Communications, Advanced Materials等期刊刊出研究论文50多篇，在Advances in Physics, Advanced Functional Materials 刊出邀请综述两篇；申请中国发明专利20项，授权12项；新获批基金委重点项目等基金5项；协办和参与国内外学术会议26次，MIT，波士顿学院等高校邀请报告20次。