Terpolymers consisting of three monomers with one electron donor unit and two electron acceptor units are promising p-type polymers for polymer solar cells (PSCs) because the incorporation of a third monomer into a copolymer backbone provides synergetic effect on physical properties such as absorption ability, charge transport, and photovoltaic performance. Currently, novel p-type terpolymers need to be developed for high-efficiency PSCs, which can be processed with eco-friendly non-halogenated solvents. In this study, a new series of terpolymers composed of 4,8-di(2,3-didecylthiophen-5-yl)-benzo[1,2-b:4,5-b′]dithiophene (BDT), 4,7-di(thien-2-yl)-5,6-difluoro-2,1,3-benzothiadiazole (DTffBT), and benzo[1,2-c:4,5-c0]dithiophene-4,8-dione (BDD) segments was synthesized and characterized for high-performance PSCs processed with non-halogenated solvents. PBDTBD terpolymers (i.e., PBDTBD-25, PBDTBD-50, and PBDTBD-75) were synthesized by adjusting different ratios of DTffBT to BDD segment (25%, 50%, and 75% of DTffBT). PBDTBD terpolymers exhibited excellent solubility in non-halogenated solvents. The optical, electrochemical, and morphological properties of PBDTBD terpolymers were successfully controlled by modulating the molar ratio of DTffBT and BDD. Moreover, a PBDTBD-50:IT-4F blended film showed homogeneous film with a favorable face-on orientation. The PBDTBD-50:IT-4F blended film showed excellent hole and electron mobility, which resulted in a superior carrier balance. PBDTBD-50-based PSCs, processed with o-xylene, achieved the highest PCE of 10.03%, which is four times higher than those of copolymer-based PSCs. The novel terpolymers composed of one electron donor unit and two electron acceptor units are expected to make a considerable contribution to the development of high-performance PSCs.

由具有一个电子给体单元和两个电子受体单元的三种单体组成的三元共聚物是用于聚合物太阳能电池（PSC）的有希望的p型聚合物，因为将第三种单体引入共聚物主链可对诸如吸收能力等物理性能产生协同作用，电荷传输和光伏性能。当前，需要开发用于高效PSC的新型p型三元共聚物，可以使用环保的非卤代溶剂进行处理。在这项研究中，由4,8-二（2,3-二癸基噻吩-5-基）-苯并[1,2- b：4,5- b ']二噻吩（BDT）组成的一系列新的三元共聚物4， 7-二（噻吩-2-基）-5,6-二氟-2,1,3-苯并噻二唑（DTffBT）和苯并[1,2- c：4,5- c合成了0]二噻吩-4,8-​​二酮（BDD）片段，并表征了用非卤代溶剂处理的高性能PSC。PBDTBD三元共聚物（即PBDTBD-25，PBDTBD-50和PBDTBD-75）是通过调节DTffBT与BDD链段的不同比例（DTffBT的25％，50％和75％）合成的。PBDTBD三元共聚物在非卤代溶剂中显示出极好的溶解性。通过调节DTffBT和BDD的摩尔比，成功控制了PBDTBD三元共聚物的光学，电化学和形态学性质。此外，PBDTBD-50：IT-4F共混膜显示出具有良好的面朝取向的均质膜。PBDTBD-50：IT-4F共混膜显示出优异的空穴和电子迁移率，从而实现了出色的载流子平衡。基于PBDTBD-50的PSC，使用o处理-二甲苯的PCE最高，达10.03％，是基于共聚物的PSC的四倍。由一个电子给体单元和两个电子受体单元组成的新型三元共聚物有望为高性能PSC的发展做出巨大贡献。