Surfactant Design Strategy for One-Pot Seedless Synthesis of Hollow Mesoporous AuAg Alloy Nanospheres
Hao Lv, Dongdong Xu, Lizhi Sun, Ben Liu
Abstract
Hollow gold (Au)-based nanostructures have recently been developed for various applications. However, current nanosynthesis approaches have not yet successfully been implemented for precisely engineering hollow Au-based nanostructures with uniform and well-defined mesoporous shell frameworks. Here, we develop an easy one-pot seedless strategy for fabricating hollow mesoporous AuAg (h-mesoAuAg) nanospheres by combining the galvanic replacement reaction with the surfactant-templated growth. Thiol-terminated multifunctional C22H45N+(CH3)2–C3H6–SH (Cl–) (C22N–SH) as the functional surfactant is the key that facilitates the formation of covalently stable C22N–S–Au(I) and C22N–S–Ag(I) intermediates. Such intermediates template in situ growth of mesoAuAg shell on initially nucleated Ag-rich seeds through the galvanic replacement reaction. Hierarchically hollow/mesoporous nanostructures and corresponding optical responses of h-mesoAuAg are also precisely engineered by tailoring synthetic parameters. With structural and compositional advantages, h-mesoAuAg nanospheres exhibit promising electrochemical performances toward methanol oxidation reaction and nonenzymatic glucose sensor.