Ultrabright Full Color Carbon Dots by Fine-Tuning Crystal Morphology Controllable Synthesis for Multicolor Bioimaging and Sensing

Abstract

In this paper, two kinds of novel carbon nanocrystals (CNCs) with different crystal morphologies (the branch-chain young sprout form (CM1) and conifer-pine form (CM2)) were obtained in a controllable way. The mechanism of crystal morphological development was explored well. When the two kinds of the CNCs were dissolved in different polar solvents, they voluntarily become "ultrafine crystals" at the moment. After that, the ultrabright full color carbon dots (UBFCCDs) have been preliminarily prepared by fine-controlling. With the evaporation of the solvents, the CNCs crystallized again, which could repeat back and forth many times. After the conditions of preparing for CDs were optimized carefully, the asprepared CDs exhibit ultrabright effects of multiexcitation and multiemission (from blue to red) and can show unique upconversion luminescence characteristics under a lower excitation wavelength of 660 nm instead of a near-infrared wavelength of 980 or 808 nm. Significantly, the QY% of the UBFCCDs can reach 78.0%, which is higher than that of the traditional hydrothermal methods of discarding precipitation and carrying out dialysis (QY% = 69.0%). The as-prepared CDs can be used for multicolor biomedical imaging in vivo and in vitro and metal ion sensing and also show their potential value for industrial applications.

Synthesis of Novel Fluorescent Carbon Quantum Dots From Rosa roxburghii for Rapid and Highly Selective Detection of o-nitrophenol and Cellular Imaging

“…In the spectrum, the characteristic peaks at 1,244, 1,637, and 1,703 cm −1 are assigned to the stretching frequencies of C–O, C=C, and C=O groups. A broad band was observed from 2,800 to 3,600 cm −1 , demonstrating the presence of O–H/N–H bonds that contribute to the dispersion of nanocrystals in polar solvents (Huo et al, 2019 ). The absorption bands at 2,950 and 1,122 cm −1 could be assigned to the stretching frequencies of C–H and C–N bonds groups, respectively.…”

Ultrasonic-Assisted Synthesis of N-Doped, Multicolor Carbon Dots toward Fluorescent Inks, Fluorescence Sensors, and Logic Gate Operations

“…The adopted avenues to obtain M-CDs are nothing more than adjusting raw materials, reaction conditions (temperatures, reaction times, reaction solvents), and/or separation methods, etc. [ 22 , 23 , 24 , 25 , 26 , 27 ] C. Dong et al prepared color-tunable CDs by a one-pot hydrothermal method, and the optimized emission of CDs progressively shifted from green to red with the adjustment of the precursor solution from alkali to acid [ 22 ]. S. K. Sahu and coworkers synthesized the multicolor emissive CDs by solvent-controlled and solvent-responded approaches [ 24 ].…”

Combinations of Superior Inorganic Phosphors for Level‐Tunable Information Hiding and Encoding

“…Due to these interesting luminous phenomena, incorporating inorganic PL materials into inks to obtain excellent optical performances of encoding patterns, gives rise to great interests in the IHE. [ 24,25 ]…”

“…Inorganic photoluminescent (PL) materials (including upconversion luminescent (UCL), down-shifting (DS), and persistent (PersL)) are very promising beneficial for designing specific optical outputs are demonstrated. [25][26][27][28][29][30][31][32][33][34] For realizing a better understanding and guidance, a recapitulatory review of revealing the relation between optical properties and artificially controllable parameters (including morphology, crystal structure, and site occupation) is very necessary. It is common that security patterns printed by the inkjet printing, screen-printing, and photolithography methods are extensively used to elevate the potential of inorganic PL materials in the IHE.…”

“…Due to these interesting luminous phenomena, incorporating inorganic PL materials into inks to obtain excellent optical performances of encoding patterns, gives rise to great interests in the IHE. [24,25] In order to obtain excellent ink performance, inorganic PL materials with excellent optical properties (including tunable output and high quantum yield (QYs)) and excellent photostability are required. Rational designing throughout the morphology, crystal structure of a host, and site occupation of dopants are essential to meet these targets.…”