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Ultralight metal foams.

Jiang B, He C, Zhao N, Nash P, Shi C, Wang Z - Sci Rep (2015)

Bottom Line: These materials are fabricated with a low-cost polymeric template and the method is based on the traditional silver mirror reaction and electroless plating.We have produced ultralight monolithic metal foams, such as silver, nickel, cobalt, and copper via this method.The plateau stress σpl was measured and found to be in agreement with the value predicted by the cellular solids theory.

View Article: PubMed Central - PubMed

Affiliation: School of Materials Science and Engineering, Tianjin University, Tianjin 300072, P.R. China.

ABSTRACT
Ultralight (<10 mg/cm3) cellular materials are desirable for thermal insulation; battery electrodes; catalyst supports; and acoustic, vibration, or shock energy damping. However, most of these ultralight materials, especially ultralight metal foams, are fabricated using either expensive materials or complicated procedures, which greatly limit their large-scale production and practical applications. Here we report a simple and versatile method to obtain ultralight monolithic metal foams. These materials are fabricated with a low-cost polymeric template and the method is based on the traditional silver mirror reaction and electroless plating. We have produced ultralight monolithic metal foams, such as silver, nickel, cobalt, and copper via this method. The resultant ultralight monolithic metal foams have remarkably low densities down to 7.4 mg/cm3 or 99.9% porosity. The metal foams have a long flat stress-train curve in compression tests and the densification strain εD of the Ni/Ag foam with a porosity of 99.8% can reach 82%. The plateau stress σpl was measured and found to be in agreement with the value predicted by the cellular solids theory.

No MeSH data available.


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Fabrication scheme of ultralight metal foams.
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f1: Fabrication scheme of ultralight metal foams.

Mentions: Figure 1 illustrates the fabrication scheme of the ultralight Ag, Ni, Co, Cu foams. These materials are prepared by starting with a polymeric template, coating the template via the silver mirror reaction, then electroless plating (Ni, Co, Cu), and subsequently burning away the template. The template employed in this study is a polymer foam used as a household cleaning eraser which is cheap and easy to purchase in the market. The polymer made from melamine resin is flexible with a three-dimensional network structure consisting of slender filaments (Supplementary Fig. S1). The melamine resin foam is an extremely open-cell foam with highly hydrophilic properties, which are advantageous for the electroless plating. The traditional method of electroless plating on dielectric templates such as a polymer involves two, often three, stages10. The polymer templates must be catalytically activated prior to the electoless plating to provide a surface that can interact with metal ions in solution causing their reduction on the surface and growth of the coating. SnCl2 and PdCl2 are most commonly used as activators for this purpose111213. However, PdCl2 is expensive and toxic. In our study, a traditional and practical method, the silver mirror reaction, was successfully used to fabricate continuous silver films in three-dimension on the polymer template as the catalytic activator prior to the electroless plating (Ni, Co, Cu).


Ultralight metal foams.

Jiang B, He C, Zhao N, Nash P, Shi C, Wang Z - Sci Rep (2015)

Fabrication scheme of ultralight metal foams.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4562267&req=5

f1: Fabrication scheme of ultralight metal foams.
Mentions: Figure 1 illustrates the fabrication scheme of the ultralight Ag, Ni, Co, Cu foams. These materials are prepared by starting with a polymeric template, coating the template via the silver mirror reaction, then electroless plating (Ni, Co, Cu), and subsequently burning away the template. The template employed in this study is a polymer foam used as a household cleaning eraser which is cheap and easy to purchase in the market. The polymer made from melamine resin is flexible with a three-dimensional network structure consisting of slender filaments (Supplementary Fig. S1). The melamine resin foam is an extremely open-cell foam with highly hydrophilic properties, which are advantageous for the electroless plating. The traditional method of electroless plating on dielectric templates such as a polymer involves two, often three, stages10. The polymer templates must be catalytically activated prior to the electoless plating to provide a surface that can interact with metal ions in solution causing their reduction on the surface and growth of the coating. SnCl2 and PdCl2 are most commonly used as activators for this purpose111213. However, PdCl2 is expensive and toxic. In our study, a traditional and practical method, the silver mirror reaction, was successfully used to fabricate continuous silver films in three-dimension on the polymer template as the catalytic activator prior to the electroless plating (Ni, Co, Cu).

Bottom Line: These materials are fabricated with a low-cost polymeric template and the method is based on the traditional silver mirror reaction and electroless plating.We have produced ultralight monolithic metal foams, such as silver, nickel, cobalt, and copper via this method.The plateau stress σpl was measured and found to be in agreement with the value predicted by the cellular solids theory.

View Article: PubMed Central - PubMed

Affiliation: School of Materials Science and Engineering, Tianjin University, Tianjin 300072, P.R. China.

ABSTRACT
Ultralight (<10 mg/cm3) cellular materials are desirable for thermal insulation; battery electrodes; catalyst supports; and acoustic, vibration, or shock energy damping. However, most of these ultralight materials, especially ultralight metal foams, are fabricated using either expensive materials or complicated procedures, which greatly limit their large-scale production and practical applications. Here we report a simple and versatile method to obtain ultralight monolithic metal foams. These materials are fabricated with a low-cost polymeric template and the method is based on the traditional silver mirror reaction and electroless plating. We have produced ultralight monolithic metal foams, such as silver, nickel, cobalt, and copper via this method. The resultant ultralight monolithic metal foams have remarkably low densities down to 7.4 mg/cm3 or 99.9% porosity. The metal foams have a long flat stress-train curve in compression tests and the densification strain εD of the Ni/Ag foam with a porosity of 99.8% can reach 82%. The plateau stress σpl was measured and found to be in agreement with the value predicted by the cellular solids theory.

No MeSH data available.


Related in: MedlinePlus