טכניון מכון טכנולוגי לישראל
הטכניון מכון טכנולוגי לישראל - בית הספר ללימודי מוסמכים  
M.Sc Thesis
M.Sc StudentElad Greenfield
SubjectDirect Mapping of the Way Surface Potential Varies when
Charged Bodies Approach in Electrolyte Solution
DepartmentDepartment of Physics
Supervisor Full Professor Sivan Uri
Full Thesis textFull thesis text - English Version


Abstract

Combining AFM with ion sensitive FET we provide a novel potentiometer capable of measuring surface potential change as small as 100µV at 0.2nm spatial resolution when two charged bodies approach in electrolyte solution. The surface potential measured when two silica surfaces approach deviates significantly from values inferred indirectly by conventional analysis of force curves. The new data elucidate the way charge redistributes between two non-identical surfaces and allow clear separation of electrostatics from other contributions to the interaction such as van der Waals and hydration forces.