中科院大连化物所Kaifeng Wu研究团队的一项最新研究揭示了使用基于InP量子点可以实现三线态敏化和光子上转换。 该项研究成果发表在2020年11月10日出版的《美国化学会志》上。

为了得到更为“绿色”的增敏剂，课题组人员从基于InP量子点调查三线态能量传递。时间分辨光谱学研究显示在只有核的量子点有微秒级空穴捕获，这可能复杂化和/或抑制能量转移。因此该课题组人员开发了InP/ZnSe/ZnS作为核/壳的量子点，可以有效地抑制空穴捕获，同时允许向表面锚定的蒽受体的三线态能量传递，效率为84%。敏化分子三线态参与三线态-三线态湮灭，实现以达到10.0%±0.1%归一化量子产率的光子上转换。这项研究表明无毒的基于InP量子点可以与先进的含有Cd或Pd的量子点不相上下，作为三线态增敏剂。

据悉，胶体半导体纳米晶体或量子点（QDs）用于分子三线态敏化对于许多光化学和光子应用很重要。目前QD增敏剂通常包含镉和铅等有毒元素。

附：英文原文

Title: Triplet Sensitization and Photon Upconversion Using InP-Based Quantum Dots

Author: Runchen Lai, Youbao Sang, Yang Zhao, Kaifeng Wu

Issue&Volume: November 10, 2020

Abstract: Molecular triplet sensitization using colloidal semiconductor nanocrystals or quantum dots (QDs) is important for many photochemical and photonic applications. Current QD sensitizers often contain toxic elements such as Cd and Pb. In order to “go green” with these sensitizers, we investigate triplet energy transfer from InP-based QDs. Time-resolved spectroscopy studies revealed picosecond hole trapping in core-only QDs, which could complicate and/or inhibit energy transfer. We therefore developed InP/ZnSe/ZnS core/shell QDs that effectively suppressed hole trapping and meanwhile allowed for triplet energy transfer to surface-anchored anthracene acceptors with an efficiency of 84%. The sensitized molecular triplets participated in triplet–triplet-annihilation, enabling photon upconversion with a normalized quantum yield reaching 10.0% ± 0.1%. This study demonstrates that nontoxic InP-based QDs can be engineered to be on par with state-of-the-art Cd- or Pb-containing QDs for use as triplet sensitizers.

DOI: 10.1021/jacs.0c09547

Source: https://pubs.acs.org/doi/10.1021/jacs.0c09547