Proton shuttle boosts triplet energy transfer efficiency

Researchers led by Kaifeng Wu at the Dalian Institute of Chemical Physics report a previously unknown mechanism called proton shuttle-assisted triplet energy transfer (PS-TET), where a transient proton shuttle accelerates spin-triplet energy transfer from ZnSe-based quantum dots to surface-attached phenol-pyridine acceptors. The process couples proton motion with electron transfer, producing a faster and more efficient transfer than pathways without the proton shuttle, and the chemistry can be tuned by modifying substituents to alter the sequence of proton-coupled steps. This mechanism offers a way to actively control triplet states, enabling optimization for catalysis and environmental applications while potentially suppressing them in solar cells and lasers where triplet states can be detrimental. The research also suggests that proton movement may occur via quantum tunneling, a detail that helps explain the temperature-insensitive transfer rates observed. In broader context, parallel efforts at institutions such as RMIT and CSIRO are pursuing related energy-management strategies in quantum batteries, highlighting a wider interest in stabilizing and controlling energy flow in molecular systems. Collectively, these findings open new avenues for designing materials with tunable energy transfer properties by leveraging proton dynamics in triplet pathways.