Flexible, self-healing and portable supramolecular visualization smart sensors for monitoring and quantifying structural damage

• Published in: Materials horizons Vol. 12; no. 1; pp. 19 - 24
• Main Authors: Jiao, Dezhi, Gu, Sihan, Cheng, Li, Li, Shuoqi, Liu, Chengbao
• Format: Journal Article
• Language: English
• Published: England Royal Society of Chemistry 02.01.2025
• Subjects: Chemical bonds; Component reliability; Corrosion; Corrosion environments; Crack initiation; Damage detection; Elastomers; Energy harvesting; Extreme environments; Hydrogen bonding; Image processing; Localized corrosion; Microcracks; Network reliability; Portable equipment; Quantitative analysis; Real time; Scale (corrosion); Self healing materials; Sensors; Smart sensors; Stress corrosion cracking; Structural damage; Structural failure; Structural health monitoring; Visual signals
• ISSN: 2051-6347; 2051-6355; 2051-6355
• DOI: 10.1039/d4mh01233j

Visually monitoring micro-crack initiation and corrosion failure evolution is crucial for early diagnosis of structural health and ensuring safe operation of infrastructures. However, existing damage detecting approaches are subject to the limited-detection of heterogeneous structures, intolerance of harsh environments, and challenge of quantitative analysis, impeding applications in structural health monitoring (SHM). Herein, we present a stretchable, semi-quantitative, instrument-free, supramolecular SHM sensor by integrating a polyurea elastomer with sensitive corrosion-probes, enabling localized corrosion monitoring and quantification of failure dynamics. Initially, a correlation between visual monitoring signals and structural health status is proposed, and sensor-based image processing software that accurately quantifies structural failure indicators (crack scale, corrosion reactivity and deterioration status) is proposed. Moreover, this sensor can be fabricated as multiple derivatives: a coating or patch covered on metallic substrates and an ionic-responsive test strip, ensuring real-time detection of the initiation of pitting, degradation events of metallic components and convenient monitoring of ion concentrations in corrosive media. Furthermore, the inherent geometric plasticity and dynamic hydrogen-bonded network validates the reliability for heterogeneous components and stability under extreme environments of sensors. This portable, smart SHM strategy established the channel-transformation model from corrosion dynamics to visual signals, exhibiting prospects for structural monitoring in offshore energy-harvesting equipment. A novel supramolecular damage sensor featuring unique ionic recognition, robust failure visualization and excellent environmental adaptability is constructed for monitoring and quantifying structural health.