Noble metal/functionalized cellulose nanofiber composites for catalytic applications. (5th November 2015)

• Record Type: Journal Article
• Authors: Gopiraman, Mayakrishnan; Bang, Hyunsik; Yuan, Guohao; Yin, Chuan; Song, Kyung-Hun; Lee, Jung Soon; Chung, Ill Min; Karvembu, Ramasamy; Kim, Ick Soo
• Is Part Of: Carbohydrate polymers. Volume 132(2015)
• Page Start: 554
• Page End: 564
• Publication Date: 2015-11-05
• Subjects: Electrospinning -- Cellulose nanocomposites -- Noble metals -- Surface modification -- Heterogeneous catalysis -- Reusability; Polysaccharides -- Periodicals; Polysaccharides -- Periodicals; Polysaccharides -- Périodiques; Electronic journals; 547.78
• DOI: 10.1016/j.carbpol.2015.06.051
• Languages: English
• ISSNs: 0144-8617

Abstract

Graphical abstract: Highlights: Noble metals (Ru and Ag) based cellulose nanofiber composites (RuNPs/CNFs and AgNPs/CNFs) were prepared. Physicochemical properties of the composites were investigated by TEM, SEM-EDS, FT-IR, XRD and XPS analyses. RuNPs/CNFs exhibited good catalytic activity toward the oxidation of benzyl alcohol. The AgNPs/CNFs obtained an excellent yield in the aza -Michael reaction of 1-phenylpiperazine with acrylonitrile. The nanocomposites are highly efficient, heterogeneous in nature, stable and reusable. Abstract: In this study, cellulose acetate nanofibers (CANFs) with a mean diameter of 325 ± 2.0 nm were electrospun followed by deacetylation and functionalization to produce anionic cellulose nanofibers ( f -CNFs). The noble metal nanoparticles (RuNPs and AgNPs) were successfully decorated on the f -CNFs by a simple wet reduction method using NaBH4 as a reducing agent. TEM and SEM images of the nanocomposites (RuNPs/CNFs and AgNPs/CNFs) confirmed that the very fine RuNPs or AgNPs were homogeneously dispersed on the surface of f -CNFs. The weight percentage of the Ru and Ag in the nanocomposites was found to be 13.29 wt% and 22.60 wt% respectively; as confirmed by SEM-EDS analysis. The metallic state of the Ru and Ag in the nanocomposites was confirmed by XPS and XRD analyses. The usefulness of these nanocomposites was realized from their superior catalytic activity. In the aerobic oxidation of benzyl alcohol to benzaldehyde, the RuNPs/CNFs system gave a better yield of 89% with 100% selectivity. Similarly, the AgNPs/CNFs produced an excellent yield of 99% (100% selectivity) in the aza -Michael reaction of 1-phenylpiperazine with acrylonitrile. Mechanism has been proposed for the catalytic systems.