Center for Chemistry of Novel & High-Performance Materials, Department of Chemistry, Zhejiang University, Hangzhou, 310027, China.
Adv Mater. 2017 Apr;29(14). doi: 10.1002/adma.201606923. Epub 2017 Mar 3.
Photoluminescence (PL) blinking of single colloidal quantum dot (QD)-PL intensity switching between different brightness states under constant excitation-and photo-bleaching are roadblocks for most applications of QDs. This progress report shall treat PL blinking and photo-bleaching both as photochemical events, namely, PL blinking as reversible and photo-bleaching being irreversible ones. Most studies on single-molecule spectroscopy of QDs in literature are related to PL blinking, which invites us to concentrate our discussions on the PL blinking, including its brief history in 20 years, analysis methods, competitive mechanisms and different strategies to battle it. In terms of suppression of the PL blinking, wavefunction confinement-confining photo-generated electron and hole within the core and inner portion of the shell of a core/shell QD-demonstrates significant advantages. This strategy yields nearly non-blinking QDs with their emission peaks covering most part of the visible window. As expected, the resulting QDs from this new strategy also show substantially improved anti-bleaching features.
光致发光（PL）猝灭 单个胶体量子点（QD）在恒定激发下在不同亮度状态之间的 PL 强度切换-光漂白是大多数 QD 应用的障碍。本进展报告将 PL 猝灭和光漂白都视为光化学反应事件，即 PL 猝灭是可逆的，而光漂白是不可逆的。文献中关于 QD 单分子光谱的大多数研究都与 PL 猝灭有关，这促使我们专注于 PL 猝灭的讨论，包括其在 20 年内的简要历史、分析方法、竞争机制以及克服它的不同策略。在抑制 PL 猝灭方面，波函数限制-将光生电子和空穴限制在核/壳 QD 的核和壳的内部-显示出显著的优势。该策略产生了几乎不猝灭的 QD，其发射峰覆盖了可见窗口的大部分。正如预期的那样，这种新策略得到的 QD 也显示出显著提高的抗漂白性能。
