Green Synthesis of Hollow and Spiny Gold and Silver Bimetallic Nanotubes for Catalytic Reduction of p-Nitrophenol

Abstract

P-nitrophenol (4-nitrophenol, 4-NP) is mostly from domestic sewage and industrial waste. 4-NP has been listed as a “priority pollutant” by USEPA. Research on noble metal nanomaterials to degrade 4-NP to p-aminophenol (4-aminophenol, 4-AP) is very important. Hollow and spiny gold and silver (Au–Ag) bimetallic nanotube is a kind of noble metal nanomaterial with a high aspect ratio, large specific surface area and good quantum size effect, they show great potential for applications in catalysis, surface-enhanced Raman spectroscopy (SERS), sensors, optoelectronics and biomedicine. Therefore, it is essential to synthesize Au–Ag bimetallic nanotubes with multispike-like shape and apply them in the field of catalysis. In this study, silver nanowires were used as sacrificial templates, Galvanic replacement reaction was carried out in chloroauric acid solution in the presence of polyvinylpyrrolidone (PVP), and hollow and spiny Au–Ag bimetallic nanotubes (HS AuAgNTs) were synthesized. It was shown that the reaction time and the amount of chloroauric acid had a significant effect on the morphology and size of the nanotubes. The catalytic reduction of 4-NP to 4-AP was carried using HS AuAgNTs as catalysts in the presence of excess sodium borohydride, the results suggest that the HS AuAgNTs have a promising potential for catalytic applications.