Self-grown Ni(OH)(2) layer on bimodal nanoporous AuNi alloys for enhanced electrocatalytic activity and stability

Au nanostructures as catalysts toward electrooxidation of small molecules generally suffer from ultralow surface adsorption capability and stability. Here, we report Ni(OH)2 layer decorated nanoporous (NP) AuNi alloys with a three-dimensional and bimodal porous architecture, which are facilely fabricated by a combination of chemical dealloying and in situ surface segregation, for the enhanced electrocatalytic performance in biosensors. As a result of the self-grown Ni(OH)2 on the AuNi alloys with a coherent interface, which not only enhances adsorption energy of Au and electron transfer of AuNi/Ni(OH)2 but also prohibits the surface diffusion of Au atoms, the NP composites are enlisted to exhibit significant enhancement in both electrocatalytic activity and stability toward glucose electrooxidation. The highly reliable glucose biosensing with exceptional reproducibility and selectivity as well as quick response makes it a promising candidate as electrode materials for the application in nonenzymatic glucose biosensors.