Surface-passivated, soluble and non-toxic graphene nano-sheets for the selective sensing of toxic Cr(vi) and Hg(ii) metal ions and as a blue fluorescent ink

Abstract

Blue fluorescent f-GNS were synthesized by an amine functionalization process, for sensing of toxic Cr(vi) and Hg(ii) metal ions. f-GNS showed a non-toxic behavior against E. coli cells and also be used as a fluorescent ink.

Cellulose-Derived Carbon Dots for Inner Filter Effect-Based Selective Sensing of Ofloxacin Antibiotics

“…The FTIR spectra of CD show main peaks at ∼3434, ∼1709, ∼1618, ∼1398, ∼ 1168, and ∼1028 cm –1 corresponding to −OH stretching, CO stretching, CC stretching, −CH 3 bending, −C–O stretching, and −SO vibrations, respectively . After oxidative treatment, wsCD show a broad peak at ∼3453 cm –1 corresponding to −OH stretching vibrations . In addition, intense peaks are observed at ∼1720 cm –1 corresponding to the CO stretching vibration, indicating increased oxygen-containing functionalities .…”

“…19 After oxidative treatment, wsCD show a broad peak at ∼3453 cm −1 corresponding to −OH stretching vibrations. 50 In addition, intense peaks are observed at ∼1720 cm −1 corresponding to the C�O stretching vibration, indicating increased oxygencontaining functionalities. 51 The peaks at ∼1643, ∼1438, ∼1404, and ∼1034 cm −1 are assigned to the −C�C stretching vibration, −C−N, −CH 3 bending vibration, and −S�O cm −1 vibration, respectively.…”

Photodegradation of Azo Dyes in Sunlight Promoted by Nitrogen–Sulfur–Phosphorus Codoped Carbon Dots

“…From the UV spectra [Figure 1(d)], two absorption peaks are observed at ∼225 nm attributed to the transition π → π* for CC groups 41 and ∼360 nm due to the transition n → π* for CO/N or OS/P groups. 42 NSP-CD are brightly fluorescent in the blue-green region with ∼10% quantum yield measured at 360 nm using quinine sulfate 43 as the reference dye. NSP-CD showed excitation independent property upon excitation with different wavelengths (300−440 nm), and maximum emission at ∼470 nm is observed (excitation wavelength ∼360 nm) as displayed in the fluorescence spectra [Figure 1(d)].…”

Nitrogen-Doped Carbon Nanoflakes by Acidic Charring of Microcrystalline Cellulose and Urea for the Rapid Removal of Imidacloprid from Water

“…N-CNF did not show any toxic characteristics toward the growth of both E. coli and B. subtilis after 5 and 24 h incubation periods (Figure 8a,b). 65,66 The nontoxic behavior of N-CNF toward both Gram-positive and Gram-negative bacteria ensures the sustainability of natural bacterial flora within the soil ammended with N-CNF which shows a possibility to extend their use in a real soil sample where they can remove the insecticide without disturbing the ecological balance of bacterial strains.…”