Synergistic effects of PtAu and PtAg nanoparticles in hydrogel composites for enhanced environmental catalysis

Bimetallic nanoparticles were successfully synthesized within hydrogel composites by the glow discharge plasma reduction method at room temperature. The addition of Au or Ag effectively stabilized the valence state of Pt and prevented its oxidation. Due to the combination of low operating temperature and high specific surface area provided by the wrinkles and porous structures of gelatin, the metal particles exhibit high dispersion within the composite. The Gel-Pt3Au-5mM and Gel-Pt3Ag-5mM achieved a complete reduction of methylene blue (MB) in just 20 and 16 s, respectively. Properly selected components alter the electron density on the surface of composites, thereby enhancing the adsorbate's binding capability and reducing the activation energy barrier. This superior catalytic performance surpasses that of monometallic catalysts in the reduction of MB.