Mitigating Dark Current in Photomultiplication Organic Photodetectors via the Charge Trap Gradient Bulk Heterojunction.

ABSTRACT: Photomultiplication-type organic photodetectors (PM-OPDs) with dispersed electron or hole traps in a bulk heterojunction (BHJ) have external quantum efficiency far exceeding unity. However, it typically requires a very low donor-to-acceptor ratio, as excess donor or acceptor molecules in the BHJ lead to a high dark current by forming dense charge trap pathways, resulting in hopping conduction. The BHJ layer with a low donor-to-acceptor ratio often associates with a high operating voltage, limiting the use of the PM-OPDs. In this study, we report the results of a new approach to reducing dark current by employing a charge trap gradient design in PM-OPD. This gradient provides two key benefits: (1) it reduces dark current by eliminating charge percolation pathways through regions with low ch

SUBMITTER: Gao J 

PROVIDER: S-EPMC12447394 | biostudies-literature | 2025 Sep

REPOSITORIES: biostudies-literature