材料和界面工程提高量子点敏化太阳电池性能

量子点敏化太阳电池效率不高的现状制约其高效率，低成本、长寿命潜质的发挥。以提高该类电池效率为目标，针对影响其效率的关键科学问题：量子点材料对太阳光捕获效率低及光生电子在传递、传输过程中复合损失严重，本项目拟基于能带耦合调控电子结构原理，研发兼具宽吸收和高导带能位特征不含铅、镉的复合结构（核壳、合金）量子点材料来提高对太阳光的捕获效率，获得高的光电流和效率；通过优化合成特性参数及后处理来降低量子点缺陷态密度，抑制量子点内部电荷复合；通过在光阳极表面包覆宽带隙高能垒层材料来减少光阳极界面电荷复合几率、提高电荷收集效率、获得高的光电压和效率。进一步阐明电荷分离、跃迁、传输及复合机制，探索材料、器件结构对器件性能的影响规律。通过项目实施，揭示量子点光电转换机理，研发效率大于15%或处于同期世界领先水平的量子点太阳电池器件，继续保持申请人课题组在该领域的国际领先地位，为其商用奠定理论基础。

The status of mean power conversion efficiency for quantum dot sensitized solar cells (QDSCs) limits the exploration of the “high efficiency, low-cost, and long lifetime” potentials. In order to solve the key scientific problems in restricting the efficiency of QDSCs: a low solar light harvesting efficiency for quantum dot materials together with a high recombination lost for photogenerated electron, and therefore improve the power conversion efficiency of QDSCs furthermore, a series of composite QD systems (including core/shell and alloy structures) without the existence of highly toxic cadmium and lead elements will be designed and synthesized on the basis of on band gap coupling theory to realize the features of wide range of light absorption and high conduction band edge for QD materials and improve the solar light harvesting efficiency and achieve high photocurrent and efficiency. Meanwhile, the charge recombination occurring inside QDs will be reduced after modifying the synthetic procedure and employing post-synthesis treatment on QDs; the charge recombination occurring between photoanode/electrolyte interfaces will be retarded after overcoating barrier layer materials, and the photovoltage and efficiency could be improved. With the implementation of this project, an efficiency up to 15% can be achieved for QDSCs. This can ensure the top position of the applicant in this target area and pave a road for their commercialization.