Graphene oxide grafted polyethylenimine electron transport materials for highly efficient organic devices

Abstract

We demonstrate that solution processed graphene oxide (GO) grafted polyethylenimine ethoxylate (PEIE) is an efficient electron transport layer for organic solar cells with an active layer that consists of poly({4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b′]dithiophene-2,6-diyl}{3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophenediyl}) (PTB7) mixed with [6,6]-phenyl C₇₁ butyric acid methyl ester (PC₇₁BM). The optimized GO:PEIE demonstrated the best efficiency of 8.21% compared to that of the GO and PEIE devices.