Benzothiadiazole-based hole transport materials for high-efficiency dopant-free perovskite solar cells: Molecular planarity effect  

作　　者：Xiang Zhou Fantai Kong Yuan Sun Yin Huang Xianxi Zhang Rahim Ghadari 

机构地区：[1]Key Laboratory of Photovoltaic and Energy Conservation Materials,Institute of Applied Technology,Hefei Institutes of Physical Science.Chinese Academy of Sciences,Hefei 230088,Anhui,China [2]University of Science and Technology of China,Hefei 230026,Anhui,China [3]Shandong Provincial Collaborative Innovation Center of Chemical Energy Storage&Novel Cell Technology,Liaocheng University,Liaocheng 252000,Shandong,China [4]Computational Chemistry Laboratory,Department of Organic and Biochemistry,Faculty of Chemistry,University of Tabriz,5166616471 Tabriz,Iran

出　　处：《Journal of Energy Chemistry》2020年第5期115-120,共6页能源化学（英文版）

基　　金：the National Key R&D Program of China(2018YFB1500101);National Basic Research Program of China(No.2015CB932200);CAS-Iranian Vice Presidency for Science and Technology Joint Research Project(No.116134KYSB20160130).

摘　　要：A new benzothiadiazole-based D-A-D hole transport material(DTBT)has been designed and synthesized with a more planar structure by introducing of thiophene bridges.The results indicate a lower band gap and quite higher hole mobility for the DTBT.Furthermore,the enhancement in molecular planarity with simple thiophene unit increases the hole mobility of DTBT(8.77×10^-4cm^2 V^-1s^-1)by about 40%.And when DTBT is used as hole transport material in perovskite solar cells,the photoelectric conversion efficiency of the corresponding dopant-free devices is also significantly improved compared with that of the conventional BT model molecule without thiophene.In terms of device stability,DTBT-based devices show a favorable long-term stability,which keep 83%initial efficiency after 15 days.Therefore,the introducing of thiophene bridges in D-A-D typed HTMs can improve the molecular planarity effectively,thereby increasing the hole mobility and improving device performance.A new benzothiadiazole-based D-A-D hole transport material（DTBT） has been designed and synthesized with a more planar structure by introducing of thiophene bridges. The results indicate a lower band gap and quite higher hole mobility for the DTBT. Furthermore, the enhancement in molecular planarity with simple thiophene unit increases the hole mobility of DTBT(8.77 × 10-4 cm2 V-1 s-1) by about 40%. And when DTBT is used as hole transport material in perovskite solar cells, the photoelectric conversion efficiency of the corresponding dopant-free devices is also significantly improved compared with that of the conventional BT model molecule without thiophene. In terms of device stability, DTBT-based devices show a favorable long-term stability, which keep 83% initial efficiency after 15 days. Therefore, the introducing of thiophene bridges in D-A-D typed HTMs can improve the molecular planarity effectively,thereby increasing the hole mobility and improving device performance.

关 键 词：HOLE transport materials PLANARITY PEROVSKITE Solar cells 

分 类 号：TM914.4[电气工程—电力电子与电力传动] O626[理学—有机化学]