Multifunctional composite hydrogels based on hydroxypropyl cellulose for catalytic degradation of organic pollutants and high-performance wearable sensors.

In this paper, the dispersion stability of graphene was effectively promoted by the introduction of hydroxypropyl cellulose (HPC), a novel composite hydrogel PAM-LMA-PDA@TiO-GN was prepared. Polyacrylamide (PAM) provided the basic three-dimensional network structure, lauryl methacrylate (LMA), as the hydrophobic monomer, constructed the hydrophobic associative micro-regions inside the hydrogel, which enhanced the structural stability, and polydopamine-coated TiO (PDA@TiO), as a nano-toughness enhancement point, which endowed the hydrogel with a stress and strain of 1026 kPa and 2519 %, respectively. Hydrogels loaded with Ag nanowires (Ag NWs) and graphene (GN) were prepared using Ag nanowires as the intercalating agent, graphene as the substrate and hydrogel as the carrier, graphene and Ag nanowires endow the hydrogels with excellent electron transport capabilities. The rate constant k for Rhodamine B (Rhb), methylene blue (MB) and 4-nitrophenol (4-NP) were 0.657, 0.528 and 0.367 min, respectively, and the hydrogel showed good stability and recoverability in the catalytic reaction. In addition, graphene and Ag nanowires endowed the hydrogel with excellent electrical conductivity, the hydrogel has high sensitivity (gauge factor = 10.46), fast response time (153 ms), and excellent cyclic stability, which can be used as a flexible sensor to detect a wide range of human activities, making it an ideal candidate for flexible sensors.