(549c) Transition Metal / Alloy Foams By Combustion Technique

Transition metal foams offer low density, high permeability and thermal conductivity which makes them attractive for fuel cell, acoustical insulation and catalysis applications[1, 2]. They have limited availability, however, as they have been synthesized in prior work by elaborate processes such as templating on dextran3 or by the dissolution of one component of an alloy[4]. Recent investigations applied combustion techniques with Hunt et al.[5] burning nanoscale nickel and aluminum to form porous structures, while Tappan et al.[2] used a metal complex as precursor. In the latter, the reactive compound was ignited under high pressure (20 atm) in an inert environment, yielding foam structures consisting of ~50% metal with balance carbon/nitrogen compounds. In the present work, we demonstrate the ability to synthesize high-purity nickel, copper and Ni-Cu alloy foams by combustion in an open container (i.e. at ambient pressure and atmosphere). This was achieved by tuning the experimental parameters during solution combustion synthesis, a technique previously utilized for oxide powder formation[6, 7]. A range of compositions were produced and characterized using XRD, SEM, BET, gas pycnometry and Microanalysis.

References: (1) Jarrah, N. A.; van Ommen, J. G.; Lefferts, L. Journal of Catalysis 2006, 239, 460-469. (2) Tappan, B. C.; Huynh, M. H.; Hiskey, M. A.; Chavez, D. E.; Luther, E. P.; Mang, J. T.; Son, S. F. Journal of the American Chemical Society 2006, 128, 6589-6594. (3) Walsh, D.; Arcelli, L.; Ikoma, T.; Tanaka, J.; Mann, S. Nature Materials 2003, 2, 386-390. (4) Hodge, A. M.; Biener, J.; Hsiung, L. L.; Wang, Y. M.; Hamza, A. V.; Satcher, J. H. Journal of Materials Research 2005, 20, 554-557. (5) Hunt, E. M.; Pantoya, M. L.; Jouet, R. J. Intermetallics 2006, 14, 620-629. (6) Patil, K. C.; Aruna, S. T.; Mimani, T. Current Opinion in Solid State and Materials Science 2002, 6, 507-512. (7) Varma, A.; Mukasyan, A.; Deshpande, K.; Pranda, P.; Erri, P. R. Materials Research Society Symposium Proceedings 2004, 113-124.