Hierarchical macrotube/mesopore carbon decorated with mono-dispersed Ag nanoparticles as a highly active catalyst

Natural wood, featuring abundant oxygen-containing functional groups, has been utilized as a reductant to synthesize monodispersed Ag nanoparticles on its surface. By further carbonization of the Ag/wood composite, wood was converted to carbon with embedded mesopore structures. Through the two-step reduction and carbonization, a macro-tube/meso-pore carbon frame with decorated mono-dispersed silver nanoparticles (Ag/C) can be conveniently synthesized. Various characterization techniques including SEM, TEM, HRTEM, BET, Raman, XRD, XPS and FT-IR have been utilized to study the material microstructure, crystalline structure, pore size and surface area and surface properties. The mechanism of Ag/wood formation has also been studied in this work. Ag/C shows outstanding activity in 4-nitrophenol and 2-nitrophenol reduction reactions with much higher reaction rate than literature reports, and no obvious activity degradation was observed after 10 cycles of durability tests. This newly developed synthetic methodology could serve as a general tool to design and synthesize other metal/carbon nanocomposite catalysts for a wider range of catalytic applications. More importantly, the utilization of a widely accessible renewable resource provides a sustainable feature of this work to reduce manufacturing cost and environmental impact.