Green Synthesis of High Quantum Yield Carbon Dots from Phenylalanine and Citric Acid: Role of Stoichiometry and Nitrogen Doping,ACS Sustainable Chemistry & Engineering

当前位置： X-MOL 学术 › ACS Sustain. Chem. Eng. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Green Synthesis of High Quantum Yield Carbon Dots from Phenylalanine and Citric Acid: Role of Stoichiometry and Nitrogen Doping
ACS Sustainable Chemistry & Engineering ( IF 7.1 ) Pub Date : 2020-03-31 , DOI: 10.1021/acssuschemeng.9b07463
Shawninder Chahal ₁ , Nariman Yousefi ₁ , Nathalie Tufenkji ₁

Affiliation

Despite a growing interest in carbon dots (CDs), notably for their potential as a more sustainable, less toxic alternative to inorganic quantum dots, the critical factors affecting their physical, chemical, and optical properties are relatively unknown, limiting their widespread use. Herein, a one-pot hydrothermal method was used to synthesize CDs from citric acid and phenylalanine. CDs were synthesized over a range of reactant ratios, from pure citric acid to pure phenylalanine and seven mixed ratios in between, achieving a quantum yield (QY) as high as 65% with a peak excitation/emission of 350/413 nm. The goal was to determine the role of stoichiometry on the chemical and structural composition of CDs, particularly its impact on nitrogen doping, and in turn its effect on QY. We showed that a wide range of reactant ratios tend toward reacting in a stoichiometric 2:1 molar ratio of phenylalanine to citric acid whereby the resulting CDs have similar chemical composition and QY. Using this ratio may lead to a more efficient and sustainable mass production process by reducing and reusing reactant waste. The QY of the CDs was found to be more dependent on the oxygen-to-carbon ratio and the relative amount of carboxyl oxygen in the CD than it was on the nitrogen-to-carbon ratio. The resulting CDs also showed Fe³⁺ sensing capabilities through static fluorescence quenching with a limit of detection of 3.5 μM. This study provides new insights which may be useful for the optimization of the green synthesis of CDs for more widespread applications.

中文翻译：

由苯丙氨酸和柠檬酸绿色合成高量子产率的碳点：化学计量和氮掺杂的作用

尽管人们对碳点（CD）的兴趣日益增长，特别是由于碳点作为无机量子点具有更可持续发展，毒性更小的替代品的潜力，但影响其物理，化学和光学性质的关键因素却相对未知，限制了其广泛使用。在此，使用一锅法水热法从柠檬酸和苯丙氨酸合成CD。在从纯柠檬酸到纯苯丙氨酸的一系列反应物比率范围内，以及在两者之间的七个混合比率范围内，合成了CD，实现了高达65％的量子产率（QY），峰值激发/发射为350/413 nm。目的是确定化学计量对CD的化学和结构组成的作用，尤其是对氮掺杂的影响，以及对QY的影响。我们表明，反应物比率的范围很广，倾向于以苯丙氨酸与柠檬酸的化学计量比为2：1的摩尔比进行反应，从而使所得的CD具有相似的化学组成和QY。使用该比率可以通过减少和再利用反应物废物而导致更有效和可持续的批量生产过程。发现CD的QY比CD与氮碳比更依赖于氧碳比和羧基氧的相对量。所得的CD也显示出Fe 发现CD的QY比CD与氮碳比更依赖于氧碳比和羧基氧的相对量。所得的CD也显示出Fe 发现CD的QY比CD与氮碳比更依赖于氧碳比和羧基氧的相对量。所得的CD也显示出Fe通过静态荧光猝灭提供³⁺感应功能，检测极限为3.5μM。这项研究提供了新的见解，可能有助于优化CD的绿色合成，以更广泛地应用。

更新日期：2020-04-01

点击分享查看原文

点击收藏

阅读更多本刊最新论文本刊介绍/投稿指南11