TY - JOUR
T1 - Unveiling the corrosion mechanism of 3-nitro-1,2,4-triazol-5-one (NTO) toward mild steel from ab initio molecular dynamics
T2 - how the “nitro-to-amino” reaction matters
AU - Guo, Ziyang
AU - Qin, Liyuan
AU - Zhao, Shuai
AU - Wang, Deqiu
AU - Lv, Xijuan
AU - Qiang, Yujie
AU - Guo, Wei
AU - Shu, Qinghai
AU - Yao, Y.
N1 - Publisher Copyright:
© 2023 The Royal Society of Chemistry.
PY - 2023/6/20
Y1 - 2023/6/20
N2 - Although NTO is unquestionably acidic, its potential to corrode weaponry and associated reaction mechanisms remain puzzling. Here, ab initio molecular dynamics (AIMD) with explicit solvation and “slow-growth” sampling approaches are utilized to identify the key steps involved in NTO induced metal corrosion. Our results affirm that the acidity of NTO originates from the lower dehydrogenation barrier of the N4 site compared to the N1 site (0.28 vs. 0.37 eV). Furthermore, NTO has the strongest adsorption on Fe(110) in a nitro-dissociation manner, revealed by using density functional theory (DFT) calculations. Notably, under the catalysis of Fe(110) and hydrogen shuttling, both NTO and its anion can realize the “nitro-to-amino” reaction within 4 ps, but the reduction barrier of the anion is higher. The surface species (*O and *OH) produced by the “nitro-to-amino” reaction serve as corrosion precursors and exacerbate the observed surface iron oxide formation in the experiments. Consequently, the surface corrosion products and azole rings, which are difficult to further decompose under mild conditions, act as a barrier to mitigate the corrosion rate. This work not only unveils a crucial issue in the application of NTO, but also highlights the importance of metal surface and hydrogen bonding in the corrosion process. Our research provides guidance for elaborating the mechanism of NTO induced corrosion at the microscopic level; it may hold for other acidic organic molecules as well. Such understanding can help in establishing corresponding protective measures.
AB - Although NTO is unquestionably acidic, its potential to corrode weaponry and associated reaction mechanisms remain puzzling. Here, ab initio molecular dynamics (AIMD) with explicit solvation and “slow-growth” sampling approaches are utilized to identify the key steps involved in NTO induced metal corrosion. Our results affirm that the acidity of NTO originates from the lower dehydrogenation barrier of the N4 site compared to the N1 site (0.28 vs. 0.37 eV). Furthermore, NTO has the strongest adsorption on Fe(110) in a nitro-dissociation manner, revealed by using density functional theory (DFT) calculations. Notably, under the catalysis of Fe(110) and hydrogen shuttling, both NTO and its anion can realize the “nitro-to-amino” reaction within 4 ps, but the reduction barrier of the anion is higher. The surface species (*O and *OH) produced by the “nitro-to-amino” reaction serve as corrosion precursors and exacerbate the observed surface iron oxide formation in the experiments. Consequently, the surface corrosion products and azole rings, which are difficult to further decompose under mild conditions, act as a barrier to mitigate the corrosion rate. This work not only unveils a crucial issue in the application of NTO, but also highlights the importance of metal surface and hydrogen bonding in the corrosion process. Our research provides guidance for elaborating the mechanism of NTO induced corrosion at the microscopic level; it may hold for other acidic organic molecules as well. Such understanding can help in establishing corresponding protective measures.
UR - http://www.scopus.com/inward/record.url?scp=85165292508&partnerID=8YFLogxK
U2 - 10.1039/d3ta02658b
DO - 10.1039/d3ta02658b
M3 - Article
AN - SCOPUS:85165292508
SN - 2050-7488
VL - 11
SP - 16049
EP - 16058
JO - Journal of Materials Chemistry A
JF - Journal of Materials Chemistry A
IS - 30
ER -