Self-healing and corrosion-sensing multifunctional coatings containing pH-sensitive TiO2-based composites

• Published in: Journal of colloid and interface science Vol. 669; pp. 912 - 926
• Main Authors: Cao, Yangyang, Wang, Zheng, Wan, Jieru, He, Yuzhu, Li, Yunqiang, Wang, Sheng, Wang, Yanli, Song, Dalei, Zhang, Tao
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.09.2024
• Subjects: Coating; Corrosion protection; Corrosion sensing; Mesoporous TiO2; Self-healing; Self-healing; Coating; Corrosion sensing; Corrosion protection; Mesoporous TiO2
• ISSN: 0021-9797; 1095-7103
• DOI: 10.1016/j.jcis.2024.05.041

[Display omitted] •The self-healing and self-sensing coatings were developed based on pH stimuli.•The coating system shows excellent self-healing and self-sensing properties.•The cooperative effect of two inhibitors protects against steel corrosion.•The corrosion sensing ability is from the color change of Phen adsorbed on steel. Polyelectrolyte-encapsulated nanocontainers can effectively respond to changes of pH and thus control the on-demand release of corrosion inhibitors. A pH-responsive release system (Phen-Tpp@MTNs-PDDA) was developed based on the cationic polyelectrolyte poly dimethyl diallyl ammonium chloride (PDDA) encapsulated mesoporous TiO2 nanocontainers (MTNs) loaded with 1,10-phenanthroline (Phen) and tripolyphosphate ions (Tpp) corrosion inhibitors. The epoxy coating (EP) embedded with Phen-Tpp@MTNs-PDDA (Phen-Tpp@MTNs-PDDA/EP) demonstrates superior self-healing properties and confers long-term protection on the metal substrate through the cooperative effect of Phen and Tpp. Simultaneously, this hybrid coating is endowed with corrosion sensing capability based on the color development originating from the interaction of Phen and carbon steel. This self-healing and corrosion-sensing multifunctional coating provides an effective strategy for the corrosion protection of metals.