Nonantibiotic-Dependent Photothermal–Chemodynamic Synergistic Antibacterial and Hemostatic Sponge Based on TiB2 Nanosheet-Decorated Gelatin/Sodium Alginate Composites

Conventional antibacterial materials face challenges in simultaneously integrating efficient antibacterial activity, rapid hemostasis, and high biocompatibility. Herein, we report a rationally designed composite sponge (TGSS) composed of a highly porous gelatin/sodium alginate (Gel/SA) matrix decorated with titanium diboride nanosheets (TiB 2 NSs). The TiB 2 NSs not only endow the TGSS with efficient near-infrared (NIR)-triggered photothermal conversion for localized thermal ablation of bacteria but also confer Fenton-like catalytic activity that converts endogenous H 2 O 2 into cytotoxic hydroxyl radicals (·OH), enabling selective oxidative damage to microbial cells. Owing to photothermal–chemodynamic synergy, TGSS achieves exceptional antibacterial performance with 99.09% inhibition against Escherichia coli ( E. coli ) and 99.99% against Staphylococcus aureus ( S. aureus ) under NIR irradiation. Concurrently, the highly porous Gel/SA scaffold promotes rapid blood coagulation via intrinsic pathway activation and physical adsorption, resulting in significantly reduced bleeding time and blood loss. Importantly, the polymeric matrix effectively immobilizes TiB 2 nanosheets (TiB 2 NSs), suppressing nanoparticle leaching and thereby mitigating potential nanotoxicity. Furthermore, TGSS demonstrated favorable biocompatibility, as evidenced by a hemolysis rate below 5% and cell viability maintained above 90% after 48 h in cytotoxicity assays. Collectively, TGSS effectively prevents bacterial infection and accelerates blood coagulation, showcasing significant potential as a multifunctional wound dressing.