Cui Mingjun, Li Xia
Key Laboratory of Impact and Safety Engineering, Ministry of Education, School of Mechanical Engineering and Mechanics, Ningbo University Ningbo 315211 China
State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics Lanzhou 730000 China.
RSC Adv. 2021 Jun 18;11(35):21607-21621. doi: 10.1039/d1ra02775a. eCollection 2021 Jun 15.
Novel nitrogen and sulfur co-doped carbon dots (N,S-CDs) were synthesized a hydrothermal procedure using citric acid (CA) and thiourea (TU) as precursors, and the corresponding corrosion protection performance was first investigated for Q235 carbon steel in 1 M HCl solution. Experimental results indicated that N,S-CDs as mixed-type corrosion inhibitors could effectively prevent Q235 carbon steel from corrosion in 1 M HCl solution, and the corrosion inhibition efficiency was improved with the increase in N,S-CD concentration. The maximum value was achieved at 400 ppm of N,S-CDs at 25 °C, which was approximately 96.6%, 94.6% and 90.55%, according to the potentiodynamic polarization curves, EIS results and weight loss measurement, respectively. Additionally, with the temperature ranging from 25 to 55 °C, the inhibition efficiency obtained from the weight loss measurement was enhanced from 90.55% to 94.04%. Such superior inhibition effect was assigned to the physisorption and chemisorption of N,S-CDs on the Q235 carbon steel surface, which was also be confirmed by XPS analysis. The adsorption of N,S-CDs onto a steel substrate conformed to the Langmuir adsorption isotherm.
采用水热法，以柠檬酸（CA）和硫脲（TU）为前驱体合成了新型氮硫共掺杂碳点（N,S-CDs），并首次研究了其在1 M HCl溶液中对Q235碳钢的相应缓蚀性能。实验结果表明，N,S-CDs作为混合型缓蚀剂能够有效防止Q235碳钢在1 M HCl溶液中发生腐蚀，且缓蚀效率随N,S-CD浓度的增加而提高。根据动电位极化曲线、电化学阻抗谱（EIS）结果和失重测量，在25℃下，当N,S-CDs浓度为400 ppm时达到最大值，分别约为96.6%、94.6%和90.55%。此外，当温度在25至55℃范围内时，通过失重测量得到的缓蚀效率从90.55%提高到94.04%。这种优异的缓蚀效果归因于N,S-CDs在Q235碳钢表面的物理吸附和化学吸附，XPS分析也证实了这一点。N,S-CDs在钢基体上的吸附符合Langmuir吸附等温线。
