Highly efficient hybrid solar cells with tunable dipole at the donor–acceptor interface

Abstract

Effects of molecular dipole at the conjugated polymer–nanocrystal interface on the energy level alignment, the exciton dissociation process, and consequently the photovoltaic performance of poly[2,6-(4,4-bis-(2-ethylhexyl)-4H-cyclopenta[2,1-b;3,4-b′]-dithiophene)-alt-4,7-(2,1,3-benzothiadiazole)] (PCPDTBT):CdSe quantum dot bulk heterojunction hybrid solar cells are systemically studied. Power conversion efficiency up to 4.0% is achieved when 4-fluorobenzenethiol is used for ligand exchange.