title: Electrochemical annealing of nanoporous gold by application of cyclic potential sweeps.
abstract: An electrochemical method for annealing the pore sizes of nanoporous gold (NPG) is reported. The pore sizes of NPG can be increased by electrochemical cycling with the upper potential limit being just at the onset of gold oxide formation. This study has been performed in electrolyte solutions including potassium chloride, sodium nitrate and sodium perchlorate. Scanning electron microscopy images have been used for ligament and pore size analysis. We examine the modifications of NPG due to annealing using electrochemical impedance spectroscopy, and cyclic voltammetry and offer a comparison of the surface coverage using the gold oxide stripping method as well as the method in which electrochemically accessible surface area is determined by using a diffusing redox probe. The effect of additives adsorbed on the NPG surface when subjected to annealing in different electrolytes as well as the subsequent structural changes in NPG are also reported. The effect of the annealing process on the application of NPG as a substrate for glucose electro-oxidation is briefly examined.
authors: Center for Nanoscience, Department of Chemistry and Biochemistry, University of Missouri-Saint Louis, Saint Louis, MO 63121, USA.
authors: Abeera
authors: A
authors: Sharma
authors: Jay K
authors: JK
authors: Bhattarai
authors: Allan J
authors: AJ
authors: Alla
authors: Alexei V
authors: AV
authors: Demchenko
authors: Keith J
authors: KJ
authors: Stine
mesh_terms: D015374:Biosensing Techniques; D058266:Dielectric Spectroscopy / Q000379:methods*; D005947:Glucose / Q000032:analysis; D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D016062:Porosity
chemical_list: D006046:Gold; D005947:Glucose
references: Chem Mater. 2007;19(16):3902-3911
references: 18820734
references: J Nanosci Nanotechnol. 2002 Dec;2(6):581-612
references: 12908422
references: Analyst. 2008 Mar;133(3):319-22
references: 18299744
references: Nano Lett. 2006 Oct;6(10):2379-82
references: 17034115
references: Phys Rev Lett. 1989 Feb 20;62(8):929-932
references: 10040374
references: Phys Rev Lett. 2006 Jul 21;97(3):035504
references: 16907511
references: Biosens Bioelectron. 2011 Apr 15;26(8):3555-61
references: 21354778
references: Nature. 2001 Mar 22;410(6827):450-3
references: 11260708
references: Langmuir. 2012 Jan 31;28(4):2251-61
references: 22004670
references: Phys Rev Lett. 1988 Jan 11;60(2):120-123
references: 10038214
references: Chem Soc Rev. 2012 Nov 7;41(21):7016-31
references: 22975622
references: Phys Rev B Condens Matter. 1995 Feb 15;51(8):5510-5513
references: 9979445