近期共轭聚合物-富勒烯太阳能电池的器件效率已突破10%并接近商业应用的标准,在科研和产业领域引起了广泛关注,伴随器件效率的提升,对有机太阳能电池器件物理过程的认识也在不断深入,本文就近年来聚合物太阳能电池的代表性工作进行综述,郑重介绍提高器件效率的新方法,涵盖三相本体异质结、反向器件、等离激元共振效应和叠层器件等热点技术;并就器件工作的物理过程进行探讨,介绍热激子分离理论、非整数次电荷复合等新观点。通过材料设计、器件表征优化和理论计算等方法对聚合物太阳能电池进行的综合研究将有力推进这一新兴领域的发展和产业化。
The efficiencies ofpolymer-fullerene solar cells (PSCs) have now exceeded 10% and are approaching 15% which is the criterion for commercial production. With the increase of the efficiency of organic solar cell, the field has drawn lots of interest. In this review, we present a detailed description on the operating principles of PSCs and an overview of recently developed techniques and lew designs that improve the commercial merit of the final product. Firstly, the principles of key steps, including photo-absorption, creation of charge-transfer (CT) state, photocurrent generation and collection, which strongly influence the device pertbrmance such as the short circuit current, open circuit voltage, fill factor and overall efficiency are identified, as well as the methods to improve these parameters and the relationship among the work steps of PSC. Theoretical analysis to the up-to-date experiments leads to the novel descriptions of the photoct, rrent generation, such as the hot exciton dissociation and non-integer-order recombination. The former one highlights that excess energy ofexciton dominates the dissociation yield, and the later one is related to the disorder property of organic solar cells. Secondly, we review advanced techniques for boosting the device performance, which include the employment of inverted structures, plasmonic effects of metal nano-particles, tandem ceils and ternary blends. Recent experiments demonstrate proper combinations of these strategies are required to achieve higher efficiencies of PSCs. Comprehensions of device physics in semiconducting polymers is necessary to optimize the performance of polymeric solar cells, which would require researches focusing on the synthesis, characterization, design and simulation of organic semiconductors. Toward a better understanding of the microscopic working mechanism of high-efficiency PSCs, multi-perspective investigations combined with first-principle calculation such as the density thnctional theory (DFT) are necessary to provide