Department of Chemical and Pharmaceutical Sciences INSTM UdR Trieste University of Trieste Via Licio Giorgieri 1 Trieste 34127 Italy.
Present address: Department of Chemistry Northwestern University 2145 Sheridan Road Evanston IL 60208 USA.
Adv Sci (Weinh). 2021 May 11;8(13):2100125. doi: 10.1002/advs.202100125. eCollection 2021 Jul.
Carbon dots (CDs), defined by their size of less than 10 nm, are a class of photoluminescent (PL) and electrochemiluminescent (ECL) nanomaterials that include a variety of carbon-based nanoparticles. However, the control of their properties, especially ECL, remains elusive and afflicted by a series of problems. Here, the authors report CDs that display ECL in water via coreactant ECL, which is the dominant mechanism in biosensing applications. They take advantage of a multicomponent bottom-up approach for preparing and studying the luminescence properties of CDs doped with a dye acting as PL and ECL probe. The dependence of luminescence properties on the surface chemistry is further reported, by investigating the PL and ECL response of CDs with surfaces rich in primary, methylated, or propylated amino groups. While precursors that contribute to the core characterize the PL emission, the surface states influence the efficiency of the excitation-dependent PL emission. The ECL emission is influenced by surface states from the organic shell, but states of the core strongly interact with the surface, influencing the ECL efficiency. These findings offer a framework of pre- and post-synthetic design strategies to improve ECL emission properties, opening new opportunities for exploring biosensing applications of CDs.
碳点（CDs）的尺寸小于 10nm，被定义为一类具有光致发光（PL）和电致化学发光（ECL）性能的纳米材料，包括各种基于碳的纳米粒子。然而，其性能的控制，特别是 ECL，仍然难以捉摸，并受到一系列问题的困扰。在这里，作者报道了通过共反应物 ECL 在水中显示 ECL 的 CDs，这是生物传感应用中的主要机制。他们利用一种多组分自下而上的方法来制备和研究掺杂有作为 PL 和 ECL 探针的染料的 CDs 的发光性质。进一步通过研究富含伯胺、甲基化或丙基化胺基的表面的 CDs 的 PL 和 ECL 响应，报道了发光性质对表面化学的依赖性。对有助于形成 PL 发射的核心的前驱体进行了研究，而表面状态则影响激发依赖性 PL 发射的效率。ECL 发射受到有机壳层表面状态的影响，但核心状态与表面强烈相互作用，影响 ECL 效率。这些发现为预合成和后合成设计策略提供了一个框架，以改善 ECL 发射性能，为探索 CDs 的生物传感应用开辟了新的机会。
