High performance organic transistors and phototransistors based on diketopyrrolopyrrole-quaterthiophene copolymer thin films fabricated via low-concentration solution processing  

作　　者：Pengcheng Gu Mengxiao Hu Shang Ding Guangyao Zhao Yifan Yao Feng Liu Xiaotao Zhang Huanli Dong Xiangke Wang Wenping Hu 

机构地区：[1]Beijing Key Laboratory for Optical Materials and Photonic Devices, Department of Chemistry, Capital Normal University, Beijing 100048, China [2]Beijing National Laboratory for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China [3]Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) & Department of Chemistry, School of Science, Tianjin University, Tianjin 300072, China [4]College of Environmental Science and Engineering, North China Electric Power University, Beijing 102206, China [5]Department of Physics &Astronautics Shonghai Jiao Tong University, Shanghai 200240, China

出　　处：《Chinese Chemical Letters》2018年第11期1675-1680,共6页中国化学快报（英文版）

基　　金：financial support from the Ministry of Science and Technology of China (Nos. 2017YFA0204503, 2016YFB0401100);the National Natural Science Foundation of China (Nos. 51725304, 91433115, 51633006, 51733004);the Strategic Priority Research Program of the Chinese Academy of Sciences (No. XDB12030300);National program for support of top-notch young professionals

摘　　要：Conjugated polymers have received considerable attentions over the past years due to their large-area potential applications via low-cost solution processing. Improving crystallinity of conjugated polymer molecules in solution-processed thin films is crucial for their efficient charge transport and thus high performance optoelectronic devices. Herein, with diketopyrrolopyrrole-quaterthiophene （PDQT） copo/ymer as an example, it is found that by simply reducing the solution concentration for spincoating meanwhile with the assistance of post-annealing, significantly enhanced film crystallinity with formation of typical single crystalline domains is obtained, which benefits from the enough space for better molecular assembly especially at the semiconductor/dielectric interface. High performance polymer transistors and phototransistors were finally constructed based on the optimal lowconcentration （2 mg/mL） spin-coated PDQT films （～12 nm）, which giving a high charge carrier mobility of 2.28 cm2 V-1 s-1 and a photoresponse on/off ratio of 2.1 ×107 at VG = 0 V under white light irradiation of 6mW/cm2. The results suggest that the bright future of PDQT crystalline films for large-area flexible integrated optoelectronic devices and the application of effective low-concentration processing approach in solution-processed organic electronics with reduced material waste.Conjugated polymers have received considerable attentions over the past years due to their large-area potential applications via low-cost solution processing. Improving crystallinity of conjugated polymer molecules in solution-processed thin films is crucial for their efficient charge transport and thus high performance optoelectronic devices. Herein, with diketopyrrolopyrrole-quaterthiophene （PDQT） copo/ymer as an example, it is found that by simply reducing the solution concentration for spincoating meanwhile with the assistance of post-annealing, significantly enhanced film crystallinity with formation of typical single crystalline domains is obtained, which benefits from the enough space for better molecular assembly especially at the semiconductor/dielectric interface. High performance polymer transistors and phototransistors were finally constructed based on the optimal lowconcentration （2 mg/mL） spin-coated PDQT films （～12 nm）, which giving a high charge carrier mobility of 2.28 cm2 V-1 s-1 and a photoresponse on/off ratio of 2.1 ×107 at VG = 0 V under white light irradiation of 6mW/cm2. The results suggest that the bright future of PDQT crystalline films for large-area flexible integrated optoelectronic devices and the application of effective low-concentration processing approach in solution-processed organic electronics with reduced material waste.

关 键 词：Conjugated polymer Thin film Low-concentration processing CRYSTALLINITY Molecular orders MOBILITY Optoelectronic property 

分 类 号：TB383.2[一般工业技术—材料科学与工程] TN32[电子电信—物理电子学]