Nanostructured silver fibers: Facile synthesis based on natural cellulose and application to graphite composite electrode for oxygen reduction

Sharifi, N ; Sharif University of Technology

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  1. Type of Document: Article
  2. DOI: 10.1016/j.ijhydene.2010.01.147
  3. Abstract:
  4. The development of cheaper electrocatalysts for fuel cells is an important research area. This work proposes a new, simpler and low-cost approach to develop nanostructured silver electrocatalysts by using natural cellulose as a template. Silver was deposited by reduction of Ag complexes on the surface of cellulose fibers, followed by heat removal of the template to create self-standing nanostructured silver fibers (NSSFs). X-Ray diffraction (XRD) showed fcc silver phase and X-Ray photoelectron spectroscopy (XPS) demonstrated that the surface was partially oxidized. The morphology of the fibers consisted of 50 nm nanoparticles as the building blocks, and they possessed a specific surface area of about 25 m2/g, which is sufficiently high for electrocatalytic applications. The NSSFs were incorporated in a graphite composite electrode. The resulting modified electrode displayed a good electrocatalytic activity for the reduction of dissolved oxygen in basic media. In an O2-saturated 0.1 M KOH solution, the overpotential to initiate the oxygen reduction reaction reduced and the limiting current increased by increasing the relative amount of silver fibers from 0 to 5 wt%
  5. Keywords:
  6. Electrocatalyst ; Oxygen reduction ; Silver fiber ; Ag complex ; Basic media ; Building blockes ; Cellulose fiber ; Electrocatalytic ; Electrocatalytic activity ; Facile synthesis ; Graphite composites ; Heat removal ; KOH solution ; Limiting current ; Modified electrodes ; Nano-structured ; Overpotential ; Oxygen reduction reaction ; Research areas ; Cellulose ; Dissolution ; Electrocatalysts ; Electrolytic reduction ; Silver ; Synthesis (chemical) ; X ray photoelectron spectroscopy ; Dissolved oxygen ; Dissolving ; Electrodes ; Fibers ; Fuel cells ; Graphite ; Silver ; Synthesis ; X ray diffraction
  7. Source: International Journal of Hydrogen Energy ; Volume 35, Issue 8 , 2010 , Pages 3258-3262 ; 03603199 (ISSN)
  8. URL: http://www.sciencedirect.com/science/article/pii/S0360319910002491