Smart Acrylic Coating, Incorporated with PAN/MOF/CNT Composite, for Real-Time and Noncontact Detection of Accidental Acid/Base Contamination

A smart acrylic coating, functionalized with a nanocomposite of polyaniline (PAN), a metal–organic framework (MOF), and carbon nanotubes (CNT), is developed as an intelligent engineering control for the real-time, noncontact detection of chemical hazards. The coating provides a dual-signal response to acid/base contamination, exhibiting a reversible, pH-dependent color shift, while simultaneously generating measurable surface-voltage fluctuations. Formulated for practical application in a commercial water-borne acrylic matrix, the coating is demonstrated to be safe and durable, with low volatile organic compound emissions (0.055 mg/m2 h) and acceptable color stability (ΔE < 4 after a month). The system shows electrical signals to chemical spills, with the surface voltage increasing from a 4.5 mV baseline to 184 mV upon acid contact and −50 mV upon ammonia exposure. The versatility of the core technology is further demonstrated in a passive near field communication tag, which functions as a chemi-responsive switch for nonline-of-sight detection within confined spaces. This work validates a multimodal sensing technology across multiple platforms, presenting a significant advancement in proactive engineering controls for chemical safety.