New horizons for carbon dots: quantum nano-photoinitiating catalysts for cationic photopolymerization and three-dimensional (3D) printing under visible light

Abstract

Citric acid-based carbon dots (CDs) as nano-photoinitiating catalysts for 3D printing.

The role of molecular fluorophores in the photoluminescence of carbon dots derived from citric acid: current state-of-the-art and future perspectives

“…40 This discovery led to many applications based on green emitting carbon dots containing HPPT on their surface. 15,20,[75][76][77][78][79][80][81] Recently, the above-mentioned 2-pyridone-based fluorophores have played an important role in the explanation of the fluorescence properties of numerous bottom-up synthesized CDs prepared from CA as a precursor, which will be further elaborated in the next sections. At this point, it is important to note the synergistic effect of the development of the CD field on the evolution of CA-based fluorescent dyes and their applications.…”

“…19 Among a great number of possible precursors studied in the bottom-up synthesis of CDs, CA and its salts have been the most frequently reported due to their high availability and ease of preparing materials exhibiting interesting luminescence properties. [20][21][22][23][24] In the early stages of CD development, a vast number of published works were focused mainly on the synthesis of CDs emitting in the blue range of the electromagnetic spectrum with the highest fluorescence quantum yields reaching near-unity. 25,26 The relatively quick progress in the synthesis of blue-emitting CDs prompted the researchers working in this field to further improve the optical properties of the resulting nanomaterials.…”

Ratiometric Multimode Detection of pH and Fe3+ by Dual-Emissive Heteroatom-Doped Carbon Dots for Living Cell Applications

“…X-ray photoelectron spectroscopy (XPS) (Figure d) of D-CDs disclosed the three main elements C, N, and O, with the peaks located at 284, 399, and 530 eV, respectively, with the atomic percentages of 66.0 (C 1s), 19.2 (N 1s), and 14.8 (O 1s). The deconvoluted XPS peaks of C 1s were at 284.4, 285.2, 286, 287.9, and 289.8 eV, which were linked to C–C/CC, C–N, CN, CO, and O–CO, respectively (Figure e). , The high-resolution N 1s spectrum revealed four different kinds of N-functionalities: pyridinic-N (398.8 eV), pyrrolic-N (399.5 eV), amino-N (400.2 eV), and graphitic-N (401.7 eV) (Figure f). , Similarly, the deconvoluted O 1s XPS spectrum exhibited well-defined peaks at 530.8, 531.3, 532.1, 533, and 533.8 eV corresponding to the O–C/C–O–C, OC–N, CO, C–OH, and O–CO bonds, respectively (Figure g). , The exact percentage of contribution calculated from the XPS analysis is presented in Table S1. The Fourier transform infrared (FTIR) spectra (Figures S1, and h) showed peaks at 1612, 1512, 1434, 1364, and 1290 to 1140 cm –1 corresponding to the stretching vibrations of the amide linkage (NH–CO), CN, CC, N–H, and C–O-related functional groups. ,,, The combined XPS and FTIR analyses ascertained the chemical composition and functionalities of the D-CD surfaces.…”

Recent Trends in Advanced Photoinitiators for Vat Photopolymerization 3D Printing

“…[ 94 ] As shown in Figure 8B, a spherical C180 buckyball hydrogel model (73 wt% water) was successfully printed by a DLP printer from acrylamide‐PEGDA ink with a tiny amount of CdS–Au nanorods (0.5 × 10 ‐6 m ). Recently, CdSe quantum dots [ 95 ] and carbon dots [ 96 ] were also explored as visible light photoinitiators for hydrogel 3D printing, due to their respective photoredox catalytic properties.…”

“…quantum dots [95] and carbon dots [96] were also explored as visible light photoinitiators for hydrogel 3D printing, due to their respective photoredox catalytic properties.…”