COLL 431 |
| A new paradigm for the investigation of interfacial molecular structure is being developed in this laboratory that involves the physical separation of an interface from bulk solution at the shear plane through emersion from solution. The emersion geometry has been successfully coupled with ellipsometry and surface vibrational spectroscopies to enable emersed layer thickness and interfacial molecular structure to be deduced. This approach has now been successfully extended to silica surfaces using ultrathin silica films immobilized on gold substrates. In this report, studies of interfacial water layers at silica surfaces as a function of pH will be described. These interfaces have been characterized using photoelastic modulation-Fourier transform infrared reflection-absorption spectroscopy (PM-IRRAS) and ellipsometry in an emersion configuration. The results from these studies will be discussed in terms of the pH-dependence of the interfacial structure and hydrodynamics and the consequences of these attributes in a variety of applications areas. |
|
Water at Interfaces
2:00 PM-5:00 PM, Tuesday, 12 September 2006 Sir Francis Drake -- Tudor Room, Oral
Division of Colloid & Surface Chemistry |