title: Electroreflectance imaging of gold-H3PO4 supercapacitors. Part I: experimental methodology.
abstract: Electroreflectance microscopy is demonstrated as a high-resolution, non-contact method to image dynamic charge distribution in integrated microsupercapacitor structures during fast voltage cycling. Electroreflectance camera images of a gold electrode H3PO4 polymer electrolyte microsupercapacitor reveal time varying charge distribution with submicron spatial resolution, millisecond time resolution, and electroreflectance resolution on the order of 500 nC cm(-2). A model describing changes in the metal electrode's optical constants as a function of free electron concentration shows good agreement with measured electroreflectance. The proposed method can be used for sensitive, non-contact measurements of charge spatial distribution, and defect and performance characterization in electrode-electrolyte microdevices.
authors.affiliation: School of Electrical and Computer Engineering, Birck Nanotechnology Center, Purdue University, West Lafayette, IN, USA.
authors.forename: Kerry
authors.initials: K
authors.lastname: Maize
authors.forename: Arpan
authors.initials: A
authors.lastname: Kundu
authors.forename: Guoping
authors.initials: G
authors.lastname: Xiong
authors.forename: Kimberly
authors.initials: K
authors.lastname: Saviers
authors.forename: Timothy S
authors.initials: TS
authors.lastname: Fisher
authors.forename: Ali
authors.initials: A
authors.lastname: Shakouri