Author : Nicholas Payne
Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (119 download)
Book Synopsis Electrochemical Scanning Probe Methods for the Investigation of Passivating Surface Films and Permeable Media by : Nicholas Payne
Download or read book Electrochemical Scanning Probe Methods for the Investigation of Passivating Surface Films and Permeable Media written by Nicholas Payne and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "Electrochemical scanning probe microscopy has exploded in popularity since the late 1980's and widespread adoption for routine materials analysis is swiftly become a reality. In practice, for any technique, widening the material scope, particularly for industrially-relevant materials that bring much greater levels of heterogeneity and complexity in structure, is accompanied by new instrument and theory development.This thesis demonstrates that electrochemical microscopy is capable of quantitative analysis of substrate permeability - a very common but challenging to acquire property in industrially-relevant composite electrodes and corroding materials. Measurements are performed on permeable materials in situ and can thus account for material swelling and active growth of surface films as well as identify electroactive nanoscale defects. Specifically we explore each of the major electrochemical microscopy methods, scanning electrochemical microscopy (SECM), scanning ion conductance microscopy (SICM) and scanning electrochemical cell microscopy (SECCM) and through a combination of experiment and simulation, we demonstrate that mass transport within permeable surface layers can be predicted and therefore isolated from the electrochemical reactivity of the substrate.With SECM, we derived and validated analytical equations that allow rapid determination of film porosity through non-linear curve fitting of routine approach curve measurements. Furthermore, we validated the possible implementations of the equations based on the morphology of the surface film and identified any limitations for routine use. For SICM, we demonstrated that the critical parameter, ionic conductivity within a permeable layer has a significant impact on routine imaging but can also be quantified with approach curves. We present for the first time, direct measurement of ionic conductivity within a permeable film with SICM using a lithium-ion battery cathode film. Finally, with SECCM we took advantage of its well-defined spatial resolution to resolve and assess the size of nanoscale defects in a polymeric thin film. We also introduced the density plot as a new analysis method for SECCM that consolidated the large data sets obtained by experiment and facilitates correlation with simulation"--