Synthesis of multi-color fluorine and nitrogen co-doped graphene quantum dots for use in tetracycline detection, colorful solid fluorescent ink, and film

Dual-emission carbon dots for sensitive fluorescence detection of metal ions and ethanol in water

“…1e, the typical peaks in FTIR spectra at 3372, 2973, 1442, 1361 and 1046 cm −1 are ascribed to N –H and O–H stretching vibration, C–H stretching vibration, C–H bending vibration, aromatic C–N stretching vibration and C–O stretching vibration, respectively. 42 The characteristic peak at 1656 cm −1 may be attributed to the stretching vibration of CC and CN. 33 As shown in Fig.…”

“…1e, the typical peaks in FTIR spectra at 3372, 2973, 1442, 1361 and 1046 cm À1 are ascribed to N-H and O-H stretching vibration, C-H stretching vibration, C-H bending vibration, aromatic C-N stretching vibration and C-O stretching vibration, respectively. 42 The characteristic peak at 1656 cm À1 may be attributed to the stretching vibration of C]C and C]N. 33 As shown in Fig. 2a, the survey spectrum shows that there are three peaks at 284.08, 399.08 and 532.08 eV, indicating that the red CDs are composed of C, N and O elements and the atomic content ratio is 77.52%, 5.44% and 17.04%.…”

“…Due to the abundant functional groups on the surface of CDs, CDs have many surface active sites, which can interact well with organic solvents. [42][43][44][45] Therefore, CDs can be sensitive to distinguish the impurities in organic solvents.…”

Test-strip and smartphone-assisted Eu-TCPE-based ratiometric fluorescence sensor for the ultrasensitive detection of tetracycline

“…27 The LOD value is far below the maximum allowable concentration of TC in milk (225 nM) as set by the European Union. 28 Compared with the other fluorescent sensors listed in Table 1, 13,23,[29][30][31][32][33][34] the Eu-TCPE sensor exhibited a higher sensitivity (14 nM) in the detection range of 0-50 mM. The colors of Eu-TCPE suspension under UV-light irradiation can be validated via the CIE chromaticity coordinates shown in the inset of Fig.…”

One-Step Synthesis of Nitrogen/Fluorine Co-Doped Carbon Dots for Use in Ferric Ions and Ascorbic Acid Detection

“…Furthermore, it has been demonstrated that the dopant atoms on the surface functional groups affect the electronic transition significantly, indicating a promising strategy for preparing nanomaterials with specific or tunable fluorescence emissions [ 38 ]. Among all the commonly used elements for doping, the introduction of F presents the electron-withdrawing effects and strong hydrogen bonding interactions, which would change the surface charge, tune the emission fluorescence and thus improve the detection capacities [ 39 , 40 , 41 , 42 ]. In our previous work, N-doped DL-malic acid-derived CDs were synthesized with blue fluorescence and a QY of 9.8% [ 37 ].…”