Preparation of carbon quantum dots from corn straw and their application in Cu2+ detection

Abstract

Water-soluble carbon quantum dots were hydrothermally produced using corn straw as the starting material and nitric acid solution as solvent, then they were introduced as fluorescent probes for the detection of Cu2+. High-resolution transmission electron microscopy and X-ray diffraction showed that the carbon quantum dots were spherical amorphous particles with a diameter of 5 nm. The surface functional groups of carbon quantum dots were observed via Fourier transform infrared spectrometry and X-ray photoelectron spectroscopy. A new approach for Cu2+ detection was designed using carbon quantum dots based on fluorescence quenching. Linear relationships between the fluorescence variation and the Cu2+ level (1 mg·L-1 to 20 mg·L-1 and 20 mg·L-1 to 500 mg·L-1) were obtained, with coefficients of determination of 0.9960 and 0.9923, respectively. The Cu2+ detection limit was 4.26 mg·L-1. The probable quenching principle between Cu2+ and the carbon quantum dots was attributed to charge transfer.

Carbon dots prepared from waste wood and residual adhesive and their use as catalysts for hydrogen production

“…Carbon dots (CDs) derived from biomass materials are emerging carbon nanomaterials with the advantages of advances in synthesis (Bian et al 2016), hydrophilicity (Ehtesabi and Massah 2021), tunability (Ma et al 2016), and optical properties (Liu et al 2013), as well as a wide variety of raw materials, especially biomass (Li et al 2020), whose sources are extensive and low-cost. CDs are commonly used in ion detection (Yang et al 2022b), fluorescence imaging (Liu et al 2017), photocatalysis (Sbacchi et al 2023), and other applications. The main structure consists of a core composed mainly of sp 2 hybridized regions, and a shell composed of sp 3 hybridized regions (Zhu et al 2015).…”

Synthesis of carbon quantum dots based on quinoa straw and their application in alkali metal ions detection

“…After testing, quinoa straw contained 46.3% cellulose, 11.6% hemicellulose, 7.53 lignin, and less ash. Compared to wheat straw and corn stover, quinoa straw has a higher cellulose content and a lower lignin content (Yang et al 2022). Chenopodium quinoa straw is highly productive, widely available, and cheap.…”

Development of biomass waste-based carbon quantum dots and their potential application as non-toxic bioimaging agents

“…9,10 Researchers started to explore the applicability of CQDs in biochar absorbent, 11 heavy metal detection. [12][13][14][15][16][17][18] antibacterial agent, 19 bioimaging. 16,20,21 photocatalytic 22 Numerous studies have successfully synthesized the CQDs from various sources such as crab-shell derived, 12 lettuce waste, 11 gs derived, 19 durian shell waste, 13 peach leaves waste, 20 oil palm waste 10,16,17,23 cashew gum, 24 cellulose-based biowaste, 14 semisolid waste of cow manure, 21,22 green pepper, 15 grapefruit peel, 25 corn straw, 18 fennel seeds 8 chitosan, glucosamine, cellulose, glucose.…”

“…[12][13][14][15][16][17][18] antibacterial agent, 19 bioimaging. 16,20,21 photocatalytic 22 Numerous studies have successfully synthesized the CQDs from various sources such as crab-shell derived, 12 lettuce waste, 11 gs derived, 19 durian shell waste, 13 peach leaves waste, 20 oil palm waste 10,16,17,23 cashew gum, 24 cellulose-based biowaste, 14 semisolid waste of cow manure, 21,22 green pepper, 15 grapefruit peel, 25 corn straw, 18 fennel seeds 8 chitosan, glucosamine, cellulose, glucose. The elements of C, H, O, and N are the primary elements found in CQDs, and the surface of CQDs can be functionalized with polar functional groups such as carboxyl, amine, and hydroxyl, which is benecial for surface passivation, which will improve the solubility of the CQDs.…”