Abstract
The adjustment of the emitting wavelength of carbon dots (CDs) is usually realized by changing the raw materials, reaction temperature, or time. This paper reported the effective synthesis of multicolor photoluminescent CDs only by changing the solvent in a one-step solvothermal method, with 1,2,4,5-tetraaminobenzene as both the novel carbon source and nitrogen source. The emission wavelengths of the as-prepared CDs ranged from 527 to 605 nm, with quantum yields (QYs) reaching 10.0% to 47.6%, and it was successfully employed as fluorescence ink. The prepared red-emitting CDs (R-CDs, λem = 605 nm) and yellow-emitting CDs (Y-CDs, λem = 543 nm) were compared through multiple characterization methods, and their luminescence mechanism was studied. It was discovered that the large particle size, the existence of graphite Ns, and oxygen-containing functional groups are beneficial to the formation of long wavelength-emitting CDs. Y-CDs responded to crystal violet, and its fluorescence could be quenched. This phenomenon was thus employed to develop a detection method for crystal violet with a linear range from 0.1 to 11 µM and a detection limit of 20 nM.
Highlights
Carbon dots (CDs), as a novel carbon nanomaterial, have been widely applied in the fields of detection [1,2], drug delivery [3,4], medical diagnosis [5,6], and biological imaging [7] due to its excellent fluorescence properties, low cell toxicity, good biological compatibility, and low cost [8,9,10]
The relative quantum yields (QYs) was calculated as follows: ΦX = ΦST (GradX/GradST)(ηX2/ηST2), where Φ is QY, Grad is the ratio of the fluorescence area to the absorbance, η is the refractive index of the solvent, ST is the standard substance, and X is the CDs sample, where ηX = ηST
The Preparation of Multiple-Color-Emissive CDs Based on Different Solvents
Summary
Carbon dots (CDs), as a novel carbon nanomaterial, have been widely applied in the fields of detection [1,2], drug delivery [3,4], medical diagnosis [5,6], and biological imaging [7] due to its excellent fluorescence properties, low cell toxicity, good biological compatibility, and low cost [8,9,10]. Some research groups discovered that adjusting the solvent is effective in preparing long wavelength-emissive CDs. Xiong et al [14] acquired all color-emissive CDs (λem ranged from 443 to 745 nm) by adjusting the type of solvent (formamide, N,N-dimethylformamide, ethanol, and concentrated sulfuric acid) and their ratios (L-glutamic acid and o-phenylenediamine as raw materials). Tian [15] and his group realized all color-emissive CDs through three different solvents (water, glycerin, and N,N-dimethylformamide), with citric acid and urea as raw materials This method requires careful control of the solvent ratios. The prepared yellow-emissive CDs were further applied as an effective fluorescence sensing platform for CV, with excellent selectivity and sensitivity
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
