Department of Chemistry, University of California, Riverside, California, 92521, USA.
Department of Chemistry, University of California, Irvine, California 92697, USA.
J Chem Phys. 2019 Nov 7;151(17):174701. doi: 10.1063/1.5125021.
In this study, the role that primary amines play during triplet energy transfer from photoexcited CdSe nanocrystals (NCs) was examined. Colloidally synthesized CdSe NCs were placed in varying concentrations of 1-propyl- or 1-octylamine, with and without 2-anthracenecarboxylic acid transmitter ligands attached. This primary amine increases upconversion quantum yield approximately 5-fold. Further addition of amine does not improve photon upconversion, as CdSe NC photoluminescence (PL) increases at the expense of triplet energy transfer. Transient absorption measurements show that the amine plays three key roles. Primary amines enhance NC PL by decreasing the nonradiative decay rate, increase the rate of triplet energy transfer, and enable the broad trap state in these CdSe NCs to participate in triplet photosensitization.
在这项研究中，研究了伯胺和辛胺在从光激发的 CdSe 纳米晶体（NCs）中的三重态能量转移过程中的作用。将胶体合成的 CdSe NCs 置于不同浓度的 1-丙胺或 1-辛胺中，同时添加或不添加 2-蒽羧酸传输配体。这种伯胺将上转换量子产率提高了约 5 倍。进一步添加胺并不会改善光子上转换，因为 CdSe NC 光致发光（PL）的增加是以牺牲三重态能量转移为代价的。瞬态吸收测量表明，该胺发挥了三个关键作用。伯胺通过降低非辐射衰减速率来增强 NC 的 PL，增加三重态能量转移的速率，并使这些 CdSe NC 中的宽陷阱态参与三重态光敏化。
