Speaker: Professor Maojie ZHANG

Institution: College of Chemistry, Chemical Engineering and Materials Science, Soochow University

Hosted by: Professor Henry He YAN

Abstract

In this work, a novel narrow-bandgap conjugated polymer acceptor (PN1) based on electron-withdrawing 3,9-bis(2-methylene-(3-(1,1-dicyanomethylene)-indanone))-5,5,11,11-tetrakis[3-((2-hexyldecyl)oxy)benzene]-dithieno[2,3-d:2 ',3 '-d ']-s-indaceno[1,2-b:5,6-b ']dithiophene as the core building block and thiophene as the linking unit was developed and applied in all-polymer solar cells (all-PSCs). The PN1 exhibits a broad and strong absorption in the region of 550-800 nm with a high maximum extinction coefficient of 1.28×105 cm-1, a high electron mobility of 9.39×10-4 cm2/V·s and more ordered molecular packing. In addition, it also possesses a relatively higher lowest unoccupied molecular orbital (LUMO) of -3.85 eV, which is beneficial to improve open circuit voltage (Voc) and reduce the energy loss of the device. By matching with the wide bandgap polymer donor PM6, the all-PSCs achieved a power conversion efficiency (PCE) of 10.5% with a large Voc of 1.0 V, a high short circuit current density (Jsc) of 15.2 mA/cm2 and a superior fill factor (FF) of 0.69. Our work demonstrated that PN1 is a promising polymer acceptor for application in all-PSCs.

About the speaker

Professor ZHANG has published over 120 papers with more than 6000 citations (h-index = 43). Developed multiple new design strategies for organic photovoltaic materials; fabricated high-performance polymer solar cells. Awards include: National Science Fund for Outstanding Young Scholars in 2014; Jiangsu province innovative and entrepreneurial talent in 2017; Web of science highly cited researcher in 2018.