Cadmium chalcogenide nanoplatelets (NPLs) have gained tremendous attention in the past decade due to their extremely narrow optical features and their special electronic properties. For the application of the NPLs as optical emitters, in (photo) catalysis or sensing, further modification of the pristine (core) NPLs can be required. Therefore, many procedures for the synthesis of crowns (lateral extension of the core NPLs), shells and particle domains on the NPLs have already been developed. CdSe/CdS core/crown NPLs are characterised by extremely short photoluminescence (PL) lifetimes and high PL quantum yields (PLQYs) and might therefore be ideal candidates for lighting applications. In this work, we show how the optical properties of CdSe/CdS core/crown NPLs, especially their PLQYs, can be strongly improved by applying a sulphur precursor with a low reactivity. Under optimised conditions, the new procedure allows the growth of uniform CdS crowns around CdSe core NPLs with various lateral sizes, thicknesses and shapes. In addition, the modified growth kinetics was investigated by various methods, including UV/vis and PL spectroscopy as well as transmission electron microscopy.

中文翻译：

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CdSe纳米片上CdS冠的生长：核心形状很重要

在过去的十年中，硫化硫镉纳米片（NPL）由于其极窄的光学特性和特殊的电子性能而受到了极大的关注。为了将NPL用作光发射器，在（光）催化或感测中，可能需要对原始（核心）NPL进行进一步修改。因此，已经开发了许多合成冠的步骤（核心非专利文献的侧向延伸），非专利文献上的壳和颗粒域。CdSe / CdS核心/皇冠NPL具有极短的光致发光（PL）寿命和高PL量子产率（PLQY）的特点，因此可能是照明应用的理想之选。在这项工作中，我们展示了CdSe / CdS核心/冠状NPL（尤其是PLQY）的光学特性，通过使用低反应性的硫前驱体可以大大改善。在优化的条件下，新程序允许在具有各种横向尺寸，厚度和形状的CdSe核心NPL周围生长均匀的CdS冠。另外，通过各种方法研究了改进的生长动力学，包括UV / vis和PL光谱以及透射电子显微镜。