Multi‐Stimuli Response of Advanced Functional Spiropyran‐Based Smart Chromic Material: Acid Vapors Sensing Applications

• DOI: 10.1002/admt.202500323
• Publication Date: 2025-05-02T03:40:13Z
• Authors: Deepika Sharma; Sachin Goyal; Kamlesh Kumar; Amit L. Sharma
• Keywords: Spiropyran; Chromic acid

Abstract Advanced functional molecules with multi‐stimuli responsiveness are crucial for multifunctional applications. One unique feature of such smart materials is their chromogenic properties, which provide real‐time indications absorption changes. Herein, the general strategy developing spiropyran (SP) based responsive material, responds to solvent polarity, light, and acids, presented. The advanced OH‐substituted SP (SP‐OH) synthesized via a simple acid‐catalyzed ether hydrolysis reaction confirmed using spectroscopic techniques. Furthermore, its solvato‐, photo‐ acido‐chromic studies investigated. solvatochromism examined in various organic solvents (TCM, DCM, DMF, DMSO, MeOH). photochromism studied under 365, 405, 530 nm light sources dark conditions. Under 365 405 sources, ring‐opening induced, however, ring‐closing induced nm, darkness. optimized time complete found be 1 5 min respectively. For ring‐closing, it at 20 min, corresponding darkness, Additionally, free‐standing SP‐OH/PVA composite film tested acidochromism acid vapors (HCl, H 2 SO 4 , HNO 3 HCOOH, CH COOH). Smart SP‐based material stimuli suggests suitability multiple stimuli‐induced chromic sensing