Carbon Nanodots from an In Silico Perspective

Abstract

Carbon nanodots (CNDs) are the latest and most shining rising stars among photoluminescent (PL) nanomaterials. These carbon-based surface-passivated nanostructures compete with other related PL materials, including traditional semiconductor quantum dots and organic dyes, with a long list of benefits and emerging applications. Advantages of CNDs include tunable inherent optical properties and high photostability, rich possibilities for surface functionalization and doping, dispersibility, low toxicity, and viable synthesis (top-down and bottom-up) from organic materials. CNDs can be applied to biomedicine including imaging and sensing, drug-delivery, photodynamic therapy, photocatalysis but also to energy harvesting in solar cells and as LEDs. More applications are reported continuously, making this already a research field of its own. Understanding of the properties of CNDs requires one to go to the levels of electrons, atoms, molecules, and nanostructures at different scales using modern molecular modeling and to correlate it tightly with experiments. This review highlights different in silico techniques and studies, from quantum chemistry to the mesoscale, with particular reference to carbon nanodots, carbonaceous nanoparticles whose structural and photophysical properties are not fully elucidated. The role of experimental investigation is also presented. Hereby, we hope to encourage the reader to investigate CNDs and to apply virtual chemistry to obtain further insights needed to customize these amazing systems for novel prospective applications.

The role of molecular fluorophores in the photoluminescence of carbon dots derived from citric acid: current state-of-the-art and future perspectives

“…The excited state phenomena of CDs examined both experimentally and computationally have recently been reviewed. 57–60…”

“…The excited state phenomena of CDs examined both experimentally and computationally have recently been reviewed. [57][58][59][60] Citrate-based molecular fluorophores (CBMFs) in CDs Due to the efforts of many research groups, the maximum PL emission wavelength of CDs has been red-shifted markedly over time; from violet-blue in the first years, through green and finally to the red and near-infrared regions more recently. As indicated previously, the hypotheses describing the PL mechanism of CDs have been evolving in several directions Piotr P. His research focuses on understanding and applying the interaction of tailored nanosystems with light, e.g.…”

A portable fiber optic sensor for the luminescent sensing of cobalt ions using carbon dots

“…More specific insights into the exact binding environment may be aided by computational modelling. 73–76…”

“…More specific insights into the exact binding environment may be aided by computational modelling. [73][74][75][76] Development of 'test strip' sensors for cobalt detection A common strategy for minimizing the cost of qualitative luminescent sensors is to fabricate 'test strips,' in which the sensing material is deployed as a thin film on a substrate, 77 such as filter paper, 19,38,48,78,79 fabric, 80 glass, 81,82 or polymer, 83 among others. The sensor can then be integrated with a simple light source for naked eye detection of analytes of interest, or even used in tandem with smart phone spectrometers for more quantitative analysis, providing a low-cost and portable detection platform.…”

Ultrafast insights into full-colour light-emitting C-Dots

“…Moreover, different methods have been proposed to control the narrowbandwidth emission in C-Dots. [31][32][33] To the best of our knowledge, most of the reported works have focused on exploring the carrier dynamics of either blue-emitting or green-emitting C-Dots. 24,25 Here, for the first time, we explored the carrier dynamics and different relaxation processes of pure blue-, green-, and red-emitting C-Dots in detail, which have remained unexplored previously.…”