Project R-16452

Organic and perovskite multilayers for efficient photon energy up-conversion (Research)

The conversion of low energy into higher energy photons provides an attractive opportunity to improve solar energy technologies and near-infrared (NIR) imaging. Several types of thin film materials which can transform two or more low energy excited states into a higher energy one, have been previously developed. Due to the non-linear nature of such optical processes, up-conversion is most efficient at high light intensities, typically well above 100 mW/cm2. This makes this materialbased approach unsuitable for applications involving sunlight or for the sensing of weak intensity photon fluxes as for example in near-infrared imagers. Here, we propose an innovative stacked diode approach relying on novel, low-cost organic- and perovskite-based semiconductor materials. Based on solid preliminary work, we will rely on low-temperature vacuum deposition and newly designed molecular semiconductors to realize multilayer stacks with up-conversion quantum efficiencies above 5%, at intensities below 10 mW/cm2, without the need for an external voltage. To achieve this, we envisage a feedback loop between material synthesis, deposition optimization, and new fundamental insights in the opto-electronics of the layer stack to minimize losses. Finally, we will investigate the potential of these new types of up-convertors for solar photocatalysis enhancement and NIR vision under low-light conditions.

01 January 2026 - 31 December 2029