Kuriya Gabriel Kajiyama, Paiva Victor Magno, de Oliveira Sanair Massafra, Teixeira Agnes Candido, de Almeida Clara Muniz da Silva, Mateus Jairo Eduardo Leiva, de Araujo Joyce Rodrigues, Maia da Costa Marcelo Eduardo Huguenin, Suguihiro Natasha Midori, D'Elia Eliane
Department of Inorganic Chemistry, Universidade Federal do Rio de Janeiro, Avenida Athos da Silveira Ramos, 149, Cidade Universitária, Rio de Janeiro 21941-909, Brazil.
Materials Metrology Division, Instituto Nacional de Metrologia, Qualidade e Tecnologia INMETRO Avenida Nossa Sra. das Graças, 50, Xerém, Duque de Caxias 25250-020, Brazil.
ACS Omega. 2025 Jul 22;10(30):33253-33269. doi: 10.1021/acsomega.5c03224. eCollection 2025 Aug 5.
In this study, carbon quantum dots (CQDs) were successfully synthesized from garlic peel, with size dimensions confirmed by TEM and DLS analyses and photochemical properties validated by UV-vis and fluorescence spectroscopy. FTIR revealed chemical similarities with the precursor, while XPS revealed the presence of nitrogen and sulfur, indicating endogenous doping. The anticorrosive performance of the CQDs was demonstrated through gravimetric, electrochemical impedance, potentiodynamic polarization, and surface analyses including scanning electron microscopy, atomic force microscopy, and X-ray photoelectron spectroscopy. The CQDs exhibited high inhibition efficiencies with sustained performance over time, achieving maximum inhibition efficiencies of 79% for 2 h and 96% for 24 h, as determined by gravimetric studies. This inhibition was primarily mediated through physical interactions, as indicated by temperature-dependent studies. Electrochemical measurements further confirm that the CQDs act as mixed-type inhibitors, exhibiting a predominant anodic effect. Surface analyses confirmed the formation of a protective and hydrophobic film on the steel surface. XPS, DLS, and zeta potential studies, along with Arrhenius equation analysis, demonstrated that the film forms through physical and chemical interactions between mild steel and quantum dot aggregates. These findings highlight the potential of using agro-industrial waste, such as garlic peel, as a sustainable precursor for the synthesis of effective corrosion inhibitors.
在本研究中，成功地从蒜皮中合成了碳量子点（CQDs），通过透射电子显微镜（TEM）和动态光散射（DLS）分析确定了其尺寸，并通过紫外可见光谱和荧光光谱验证了其光化学性质。傅里叶变换红外光谱（FTIR）显示与前驱体具有化学相似性，而X射线光电子能谱（XPS）显示存在氮和硫，表明存在内源性掺杂。通过重量法、电化学阻抗、动电位极化以及包括扫描电子显微镜、原子力显微镜和X射线光电子能谱在内的表面分析，证明了CQDs的防腐性能。重量法研究表明，CQDs表现出高抑制效率且性能随时间持续，2小时内最大抑制效率达到79%，24小时内达到96%。温度依赖性研究表明，这种抑制主要通过物理相互作用介导。电化学测量进一步证实，CQDs作为混合型抑制剂，表现出主要的阳极效应。表面分析证实了在钢表面形成了一层保护性疏水膜。XPS、DLS和zeta电位研究以及阿伦尼乌斯方程分析表明，该膜是通过低碳钢与量子点聚集体之间的物理和化学相互作用形成的。这些发现突出了利用农业工业废料（如蒜皮）作为合成有效腐蚀抑制剂的可持续前驱体的潜力。
