posted on 2020-08-20, 14:35authored byVictor Gray, Zhilong Zhang, Simon Dowland, Jesse R. Allardice, Antonios M. Alvertis, James Xiao, Neil C. Greenham, John E. Anthony, Akshay Rao
Triplet energy transfer
between inorganic quantum dots (QDs) and
organic materials plays a fundamental role in many optoelectronic
applications based on these nanocomposites. Attaching organic molecules
to the QD as transmitter ligands has been shown to facilitate transfer
both to and from QDs. Here we show that the often disregarded thiol
anchoring group can achieve quantitative triplet energy transfer yields
in a PbS QD system with 6,11-bis[(triisopropylsilyl)ethynyl]tetracene-2-methylthiol
(TET-SH) ligands. We demonstrate efficient triplet transfer in a singlet
fission-based photon multiplication system with 5,12-bis[(triisopropylsilyl)ethynyl]tetracene
generating triplets in solution that transfer to the PbS QDs via the
thiol ligand TET-SH. Importantly, we demonstrate the increased thermal
stability of the PbS/TET-SH system, compared to the traditional carboxylic
acid counterpart, allowing for higher photoluminescence quantum yields.