writer：Zhao, LN (Zhao, Lina) [1] ; Qiu, L (Qiu, Lei) [1] ; Wang, YY (Wang, Yanyun) [1] ; Ge, SJ (Ge, Sujuan
keywords：Carbon quantum dotsHydrothermal methodPomelo peel wasteScale inhibitor
source：期刊
Issue time：2022年
Fruit Shatian pomelo peel is a common solid biological waste. This article reports the environmentally friendly synthesis of carbon quantum dots from Shatian pomelo peel waste by hydrothermal method. The synthesized carbon quantum dots (named PCA-CQDs) were characterized by transmission electron microscope (TEM), Fourier transform infrared (FT-IR) spectroscopy, X-ray photoelectron spectroscopy (XPS), ultraviolet-visible spectroscopy (UV-vis) and excitation-dependent fluorescence emission spectroscopy. The resultant carbon quantum dots were spherical, and the average particle diameter was measured to be 5 nm. The surface of PCA-CQDs has been successfully modified with functional oxygen-containing functional groups such as hydroxyl and carboxyl groups. Therefore, PCA-CQDs exhibit excellent water solubility and calcium ion chelating properties. Most importantly, PCA-CQDs were used as a new type of green scale inhibitor for inhibiting the CaSO4 and CaCO3 scale for the first time, and the scale inhibition efficiency can reach more than 95 %. By observing the changes of the scale crystals in the SEM image, it is speculated that the mechanism of PCA-CQDs inhibiting calcium scale may include chelation, dispersion and lattice distortion.