Integrated manufacturing of REciclable multi-material COmposites for the TRANSport sector
Fibrillization of Non?Fullerene Acceptors Enables 19% Efficiency Pseudo?Bulk Heterojunction Organic Solar Cells
The structural order and aggregation of non?fullerene acceptors (NFA) are critical toward light absorption, phase separation and charge transport properties of their photovoltaic blends with electron donors, and determine the power conversion efficiency (PCE) of the corresponding organic solar cells (OSCs). In this work, we demonstrate the fibrillization of small molecular NFA L8?BO with the assistance of fused?ring solvent additive 1?fluornaftalen (FN) to substantially improve device PCE. Molecular dynamics simulations show that FN attaches to the backbone of L8?BO to enhance the intermolecular packing along the conjugated backbone, inducing one?dimensional self?assembly of L8?BO into fine fibrils with a compact polycrystal structure. The L8?BO fibrils are incorporated into a pseudo?bulk heterojunction (P?BHJ) active layer with D18 as donor, and shows enhanced light absorption, charge transport and collection properties, leading to enhanced PCE from 16.0% to an unprecedented 19.0% in the D18/L8?BO binary P?BHJ OSC, featuring a high fill factor of 80%. This work demonstrates a strategy for fibrillating NFAs toward enhanced performance of OSCs.This article is protected by copyright. All rights reserved
» Publication Date: 23/11/2022
This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement Nº 768737
