AFM force measurements between gold and silver surfaces treated in ethyl xanthate solutions: Effect of applied potentials

作者：Li Zuoli; Yoon Roe Hoan^*

来源：Minerals Engineering, 2012, 36-38: 126-131.

DOI：10.1016/j.mineng.2012.03.013

• Hydrophobic force
• Gold
• Silver
• Chemisorption
• Xanthate
• Potential

Many investigators measured surface forces between hydrophobic macroscopic surfaces using atomic force microscope (AFM). Some investigators observed long-range attractions and attributed them to the presence of hydrophobic forces, while others suggested that they are artifacts of the nano-bubbles and cavities associated with the hydrophobic surfaces. Still others suggested that the long-range attractions are due to the electrostatic interactions between charged patches present on opposing surfaces and hence are unrelated to surface hydrophobicity. In the present work, we have measured long-range attractions between gold- (or silver-) coated surfaces hydrophobized in potassium ethyl xanthate (KEX) solutions at pH 9.2 under controlled potential conditions. The results of our AFM force measurements are consistent with those of the contact angle and voltammetry experiments, indicating that the long-range attractions are hydrophobic forces.

• 出版日期2012-10
• 单位Virginia Tech; 美国弗吉尼亚理工大学(Virginia Tech)