Author : Jeremy Brian Trombley
Publisher :
ISBN 13 :
Total Pages : 240 pages
Book Rating : 4.:/5 (115 download)
Book Synopsis Studies of Electrochemical Charge Transfer Between Metals and Aqueous Solutions Using Atomic Force Microscopy by : Jeremy Brian Trombley
Download or read book Studies of Electrochemical Charge Transfer Between Metals and Aqueous Solutions Using Atomic Force Microscopy written by Jeremy Brian Trombley and published by . This book was released on 2014 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt: Previous studies have demonstrated that the oxygen reduction-oxidation couple of dissolved oxygen in water is responsible in some instances for charging insulating and semiconducting materials. Because a thin film of water is present on most surfaces exposed to humid air, a complete understanding of the phenomenon would be beneficial to many fields of research including surface science, electrochemistry and electronics. In this work, we lay down the theoretical framework for the charging of metal surfaces from the oxygen redox couple. Gold and platinum were chosen to be the focus of the model due to their wide usage in technological and scientific fields, as well as their inertness. This model can be easily generalized to any metal and any number of other redox couples. More evidence is given in the debate of whether clean gold and platinum are hydrophilic or hydrophobic. We have determined these surfaces to be hydrophobic. The effectiveness of UV/ozone and ethanol cleaning of gold were examined using Kelvin probe force microscopy. We determined that the work function of the gold surface prepared with a simple ethanol rinse is the same as that prepared by a UV/ozone cleaning step followed by an ethanol rinse. Both procedures also resulted in a strongly hydrophobic surface. A long-range hydrophobic force was found to dominate, preventing measurement of the force due to charge transfer mediated by the oxygen redox couple. Some evidence is given that nanobubbles are the source of the hydrophobic force. The influence of pH and different electrolytes is reported. The impact of changing the gaseous environment surrounding the water was tested. Atmospheres of air, nitrogen and oxygen did not have a significant influence on the force measurements within the water.