Fabrication of Meso-Porous Sintered Metal Thin Films by Selective Etching of Silica Based Sacrificial Template.
Meso-porous metal materials have enhanced surface energies offering unique surface properties with potential applications in chemical catalysis, molecular sensing and selective separation. In this paper, commercial 20 nm diameter metal nano-particles, including silver and copper were blended with 7 nm silica nano-particles by shear mixing. The resulted powders were cold-sintered to form dense, hybrid thin films. The sacrificial silica template was then removed by selective etching in 12 wt% hydrofluoric acid solutions for 15 min to reveal a purely metallic meso-porous thin film material. The impact of the initial silica nano-particle diameter (7-20 nm) as well as the sintering pressure (5-20 ton·m-2) and etching conditions on the morphology and properties of the final nano-porous thin films were investigated by porometry, pyknometery, gas and liquid permeation and electron microscopy. Furthermore, the morphology of the pores and particle aggregation during shear mixing were assessed through cross-sectioning by focus ion beam milling. It is demonstrated that meso-pores ranging between 50 and 320 nm in average diameter and porosities up to 47% can be successfully formed for the range of materials tested.
Institute for Frontier Materials, Deakin University, Pigdons Road, Waurn Ponds 3216, Victoria, Australia. ludovic.dumee@deakin.edu.au.|Institute for Sustainability and Innovation, College of Engineering and Science, Victoria University, Hoppers Lane, Werribee 3030, Victoria, Australia. ludovic.dumee@deakin.edu.au.
Ludovic F
LF
Dumée
Institute for Frontier Materials, Deakin University, Pigdons Road, Waurn Ponds 3216, Victoria, Australia. mary.she@deakin.edu.au.
Fenghua
F
She
Institute for Sustainability and Innovation, College of Engineering and Science, Victoria University, Hoppers Lane, Werribee 3030, Victoria, Australia. mikel.duke@vu.edu.au.
Mikel
M
Duke
Institute for Sustainability and Innovation, College of Engineering and Science, Victoria University, Hoppers Lane, Werribee 3030, Victoria, Australia. stephen.gray@vu.edu.au.
Stephen
S
Gray
Institute for Frontier Materials, Deakin University, Pigdons Road, Waurn Ponds 3216, Victoria, Australia. peter.hodgson@deakin.edu.au.
Peter
P
Hodgson
Institute for Frontier Materials, Deakin University, Pigdons Road, Waurn Ponds 3216, Victoria, Australia. lingxue.kong@deakin.edu.au.
Lingxue
L
Kong
meso-porous metal materials; metal nano-particle sintering; metal particle coalescence; silica template etching; surface texturing