Bulk Heterojunction Upconversion Thin Films Fabricated via One-Step Solution Deposition.

Hu, Manchen; Belliveau, Emma; Wu, Yilei; Narayanan, Pournima; Feng, Demeng; Hamid, Rabeeya; Murrietta, Natalia; Ahmed, Ghada H et al. · ACS Nano · 2023

basic_science · Level V

Where this comes from

Abstract

Upconversion of near-infrared light into the visible has achieved limited success in applications due to the difficulty of creating solid-state films with high external quantum efficiency (EQE). Recent developments have expanded the range of relevant materials for solid-state triplet-triplet annihilation upconversion through the use of a charge-transfer state sensitization process. Here, we report the single-step solution-processed deposition of a bulk heterojunction upconversion film using organic semiconductors. The use of a bulk heterojunction thin film enables a high contact area between sensitizer and annihilator materials in this interface-triplet-generation mechanism and allows for a facile single-step deposition process. Demonstrations of multiple deposition and patterning methods on glass and flexible substrates show the promise of this materials system for solid-state upconversion applications.