Developing efficient anodic electrocatalyst: Three-dimensional interconnected network of bimetallic Pd–Ni aerogel for advanced electrocatalysis of ethanol

Abstract

This paper introduces a valuable and easy strategy for connecting metallic nanoparticles to assemble a three-dimensional (3D) network of bimetallic palladium-nickel aerogel. This research provides several unique advantages (e.g., facile, surfactant-free, one-pot, and fast) without any chemical destabilizer compounds. The 3D metallic superstructure is formed during the reduction of Ni²⁺ and Pd²⁺ ions by adding NaBH₄, followed by CO₂ supercritical drying. Additionally, the gelation kinetics are explored by raising the temperature to create an efficient anisotropic atmosphere to assemble the 3D Pd-Ni hydrogels. This study demonstrated that the alteration in anisotropic conditions affects the formation of a 3D hydrogel. The production of a 3D network assembled by the extended nanowires with high porosity and plenty of open pores is confirmed by various analyses. The Pd-Ni aerogel is employed as a self-supported electrocatalyst for decomposing EtOH fuel and reflects the more prominent electrocatalytic activity relative to Pd/C. The existence of nickel will facilitate the adsorption of hydroxyl groups on the surface of the resulting aerogel. These adsorbed hydroxyls react with the generated intermediates and release the blocked active sites by carbonaceous intermediates, thereby affecting efficiently the ethanol oxidation.