One-Pot Hydrothermal Synthesized Nitrogen and Sulfur Codoped Carbon Dots for Acid Corrosion Inhibition of Q235 Steel

Abstract

N and S codoped carbon dots having good water solubility have been successfully made by a novel hydrothermal method and characterized by FTIR, XPS, and TEM. The as-synthesized CDs were carbon particles rich in polar functional groups less than 10 nm in size. Electrochemical measurements, gravimetry, and surface analysis methods were utilized to examine the inhibition characteristics and adsorption mechanism of CDs on the carbon steel in acid pickling solutions. Electrochemical measurements verified that the CDs displayed adequate protection with high inhibition efficiency of 97.8%. The long-term weightloss experiments up to 72 h further confirmed the excellent corrosion inhibition at room temperature and 313 K. The results presented are helpful for the formulation of more effective acid pickling corrosion inhibitors.

One-step facile preparation of carbon dots with high fluorescence quantum yield and application in rapid latent fingerprint detection

“…It is well known that surface defects introduced by N and S co-doping affect the graphitization degree of CDs. 30,33 Experiments showed that the GCDs and GCDs-starch prepared in this study exhibited strong uorescence, and our GCDs-starch powder formed a high contrast with the background for LFP detection.…”

“…6) showed stretching vibrations for O–H at 3383 cm −1 , C–H at 2919 cm −1 , CC/CO at 1594 cm −1 , N–H at 1455 cm −1 , C–N at 1400 cm −1 , C–S at 1472 cm −1 , SO at 1475 cm −1 , and C–O at 1300 cm −1 . 28,30–33 These peaks were also observed in the FTIR spectrum of GCDs-starch, which combined the FTIR peaks for starch, GCDs-starch powder, and GCDs and indicated that GCDs were wrapped around the starch granules (Fig. 6).…”

A universal strategy for green and in situ synthesis of carbon dot-based pickling solution

“…Remarkably, the resultant CDs exhibited a prominent inhibition efficiency of 96% at 100 mg L −1 . 17 Thereafter, Yang, 24 Ye, 25 Luo, 26 He, 22 Zhang, 28 Chen, 18 Yadav, 19 Ye, 20 Cui, 23 Guo, 21 Zhang 27 et al adopted ionic liquid-functionalized CDs, N-doped CDs or N, S co-doped CDs as corrosion inhibitors for carbon steel, copper or aluminium alloy in a salt solution or acid solution. Almost all the CDs exhibited an excellent corrosion inhibition efficiency of more than 90% even at low concentrations.…”

“…[12][13][14][15][16] Fortunately, in recent years, CDs have also been used as a novel and green corrosion inhibitor, and they exhibited remarkable corrosion inhibitory actions for multiple metals in acid corrosive solution. [17][18][19][20][21][22][23][24][25][26][27][28] For instance, Zhao's group obtained CDs from 4-aminosalicylic acid via solvothermal treatment and used them as an efficient corrosion inhibitor for carbon steel in acid solution. Remarkably, the resultant CDs exhibited a prominent inhibition efficiency of 96% at 100 mg L −1 .…”

“…All the above literature fails to adopt low-cost and easily available raw materials. Even some precursors such as 4-aminosalicylic acid, 17,18 thiourea 18,19,21,23,27 and o-phenylenediamine 19,21,22,27 are toxic, potentially generating poisonous by-products and gases during the synthesis processes, thereby being harmful to the environment and posing a threat to the health of operators; (2) high energy-consuming and time-consuming processes. All the above reports utilize a hydrothermal/solvothermal approach to obtain CDs, leading to high energy consumption during the heating.…”