Scanning probes for new energy materials: Probing local structure and function
a1 Nuclear Science and Engineering Department, Massachusetts Institute of Technology; leewy@mit.edu
a2 Mechanical Engineering and Materials Science and Engineering Departments, Stanford University; fbp@cdr.stanford.edu
a3 Materials Science and Engineering, University of Pennsylvania; xich@seas.upenn.edu
a4 Materials Science and Engineering, University of Pennsylvania; ssn@seas.upenn.edu
a5 Materials Science and Engineering, University of Pennsylvania; bonnell@lrsm.upenn.edu
a6 Metallurgical and Materials Engineering, Colorado School of Mines; rohayre@mines.edu

Abstract
Atomic force microscopy (AFM)-based impedance spectroscopy provides localized impedance information of materials and interfaces at the nanoscale by utilizing the conductive AFM tip as a moving electrode to detect current response as a function of time and frequency under controlled environments. This capability enables AFM-based nanoscale impedance measurements to play a unique role in enhancing our understanding of many electronic and electrochemical devices. This article introduces the central concepts of AFM-based impedance measurement and reviews recent examples applying this technique to a variety of functional materials systems, in particular focusing on fuel cells, lithium-ion batteries, photoactive biomembranes, as well as other application examples.
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