BNL Home

 

Filling the Gaps in Understanding Nanoporous Steel

What is the scientific achievement?

Nanoporous materials have great application potential due to their high surface area, bi-continuous structure, and low cost of synthesis. CFN users from Stony Brook University used X-ray nano-tomography and X-ray fluorescence microscopy to reveal the three-dimensional (3D) morphology and elemental distributions within nanoporous steel alloys made by a liquid metal dealloying process. 

Why does this achievement matter?

Establishing structure/ property relationships in nanoporous materials and facilitating the quantitative processing by liquid metal dealloying will guide design of new materials by this method.

What are the details?

Nanoporous materials, especially those fabricated by liquid metal dealloying processes, possess great potential in a wide range of applications due to their high surface area, bicontinuous structure with both open pores for transport and solid phase for conductivity or support, and low material cost. Here, we used X- ray nanotomography and X-ray fluorescence microscopy to reveal the three- dimensional (3D) morphology and elemental distribution within materials. Focusing on nanoporous stainless steel, we evaluated the 3D morphology of the dealloying front and established a quantitative processing−structure−property relationship at a later stage of dealloying. The morphological differences of samples created by liquid metal dealloying and aqueous dealloying methods were also discussed. We concluded that it is particularly important to consider the dealloying, coarsening, and densification mechanisms in influencing the performance, determining, critical 3D parameters, such as tortuosity, pore size, porosity, curvature, and interfacial shape.

CFN Capabilities:

CFN Nanofabrication Facility was used for sample fabrication, and some characterization was performed using scanning electron microscopy in the Materials Synthesis Facility.

Publication Reference

Chonghang Zhao,1 Takeshi Wada,2 Vincent De Andrade,3 Garth J. Williams,4 Jeff Gelb,5 Li Li,4 Juergen Thieme,4 Hidemi Kato,2 and Yu-chen Karen Chen-Wiegart1,3  Three-Dimensional Morphological and Chemical Evolution of Nanoporous Stainless Steel by Liquid Metal Dealloying, ACS Applied Materials & Interfaces 9, 34172 (2017).

DOI: 10.1021/acsami.7b04659

Acknowledgement of Support

The development of PyXRF software was supported by LDRD grant, funded by Brookhaven National Laboratory. This research used resources and Submicron Resolution X-ray Spectroscopy Beamline (SRX, 5-ID) of the National Synchrotron Light Source II, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Brookhaven National Laboratory under Contract No. DE-SC0012704. This research used resources of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. K. Chen-Wiegart acknowledges support by the Department of Materials Science and Chemical Engineering, the College of Engineering and Applied Sciences, and the Stony Brook University, as well as by the Brookhaven National Laboratory under Contract No. DE-SC0012704.

2018-12961  |  INT/EXT  |  Media & Communications Office