Facile and Purification-Free Synthesis of Nitrogenated Amphiphilic Graphitic Carbon Dots

Abstract

The emerging carbon-based quantum dots have been attracting attention because of their tremendous potential for optoelectronic and biomedical applications, which is due to their unique and size-tunable optical properties, their ability to be functionalized, and their biocompatibility. Here, we report the facile one-step synthesis of highly fluorescent and amphiphilic n-doped graphitic carbon dots (N-GCDs) using a fumaronitrile (FN) precursor. An interesting property of the prepared GCDs is their near pH neutral dispersibility without refinement, which stands in contrast to reported methods. This finding indicates that our approach could lead to low-cost and efficient processability that is scalable and environmentally friendly. In addition, we find that our N-GCDs have high density of graphitic structure such as sp2-hybridized carbon and tiny amounts of defect by near-edge X-ray absorption fine structure (NEXAFS) results. Finally, to confirm the electro-optical behavior of N-GCDs on photovoltaic devices, we fabricate iPSCs consisting of ITO/PEIE/PTB7:PC71BM (+ N-GCDs)/MoO3/Ag. Using this effective approach, we demonstrate the highest conversion efficiency of ∼8.6% resulting from improved photoresponsibility and charge transport based on various charge and energy transfer dynamics. Also, we believe that the shape, size and functionality of these GCDs can be controlled using other chemical species to provide a variety opportunities for use in optoelectronics, biological applications, and sensors.

Chemically modulated graphene quantum dot for tuning the photoluminescence as novel sensory probe

“…In the case of HFHPB-GQD, 245 nm (5.06 eV) and 291 nm (4.26 eV) were observed for the transition of σ and π orbitals to LUMO2728. According to the previous reports29, the energy difference (δE) between σ and π orbitals should be below 1.5 eV for a triple ground state. The energy difference of GQD and HFHPB-GQD have been calculated to be 1.2 eV and 0.8 eV, respectively, which are probable value for triplet ground state of carbene (<1.5 eV).…”

Facile synthesis of N-rich carbon quantum dots from porphyrins as efficient probes for bioimaging and biosensing in living cells

“…The peak at 3,015 cm -1 comes from the stretching vibration of N-H in CQDs. 38 The peak at 1,036 cm -1 originates from the C-O-C stretching vibration. The bimodal stretching vibration peak of -NH lies at 3,015 cm -1 and the characteristic absorption bands of the C-N stretching vibration lie at 1,381 cm All these functional groups contribute to the excellent aqueous solubility of CQDs.…”

Enhancing Light Absorption and Charge Transfer Efficiency in Carbon Dots through Graphitization and Core Nitrogen Doping

“…a) fs-TAS spectra at different time delays(1,5,10,25, 100, 200, 500 ps, 1, 6ns; gray dashed line before excitation) in P i buffer (pH 6). a) fs-TAS spectra at different time delays(1,5,10,25, 100, 200, 500 ps, 1, 6ns; gray dashed line before excitation) in P i buffer (pH 6).…”