Building Supramolecular Chirality in Bulk Heterojunctions Enables Amplified Dissymmetry Current for High-Performing Circularly Polarized Light Detection

Abstract

Chiral supramolecular architectures deliver desired properties and functions to artificial systems. The recently developed direct circularly polarized light (CPL) detection is based on electronic devices with chiral active layers that inform photocurrent dissymmetry (gsc) upon illuminations of opposing CPL. Due to limited absorption dissymmetry (gabs) in the chiral active layers, exploring the prospect of creating additional gsc in chiral electronic devices is becoming increasingly relevant. In particular, rationalizing the corresponding amplification mechanisms is still challenging. Here, we achieve accurate CPL detection through an amplified gsc from bulk heterojunction (BHJ) small-molecule organic solar cells (OSCs) with supramolecular chirality. The alternating preferential and nonpreferential CPL illuminations cause a difference in maximum absorption position across the chiral active layer, resulting in differences in exciton separation and charge recombination, transport, and collection. These differences contribute to additional difference in photocurrent output and the amplified gsc in the chiral OSCs. From the perspective of device structure, our study likely provides insights into the amplified gsc in chiral electronic devices for direct CPL detection.