Polyamide/ <scp> SiO ₂ </scp> /Gelatin In Situ Composite From <scp>BIC</scp> /Sol–Gel Co‐Reaction for Dual Applications in Hg ²⁺ Electrochemical Probing and Both Anionic/Cationic Dyes Removal

ABSTRACT In this study, a novel polyamide (PA)/SiO 2 /gelatin (GL) in situ hybrid material (PA‐Si‐GL) was successfully prepared at room temperature by introducing amphoteric biomass, GL, as a reaction substrate into benzoxazine‐isocyanide chemistry (BIC)/sol–gel reaction system. The systematic characterization of PA‐Si‐GL's chemical structure and fundamental properties was implemented subsequently. The in situ integration of GL with diverse N,O‐containing segments (amide, phenol OH, and SiOSi) present in PA/SiO 2 fraction could strengthen the affinity between PA‐Si‐GL and Hg 2+ /dyes. PA‐Si‐GL's binding for Hg 2+ was reasonably utilized to realize the probing of this highly poisonous heavy metal. With PA‐Si‐GL as the active modifier, the modified glassy carbon electrode (GCE) (termed as PA‐Si‐GL/GCE) exhibited a specific enrichment‐enhanced electrochemical response toward Hg 2+ , with a detection limit as low as 2.8 × 10 −10 mol/L. Concurrently, PA‐Si‐GL can remove both anionic (Congo red [CR]) and cationic (methylene blue [MB]) dyes from contaminant water. The maximum adsorption capacities of PA‐Si‐GL for CR/MB reached 680.1/1001.3 mg/g (298 K), respectively. Mechanistic studies regarding Hg 2+ probing and dyes adsorption by PA‐Si‐GL were carried out by the combination of experimental comparison and chemical calculation.