title: Spectroelectrochemical Signatures of Capacitive Charging and Ion Insertion in Doped Anatase Titania Nanocrystals.
abstract: Solution-processed films of colloidal aliovalent niobium-doped anatase TiO2 nanocrystals exhibit modulation of optical transmittance in two spectral regions-near-infrared (NIR) and visible light-as they undergo progressive and reversible charging in an electrochemical cell. The Nb-TiO2 nanocrystal film supports a localized surface plasmon resonance in the NIR, which can be dynamically modulated via capacitive charging. When the nanocrystals are charged by insertion of lithium ions, inducing a well-known structural phase transition of the anatase lattice, strong modulation of visible transmittance is observed. Based on X-ray absorption near-edge spectroscopy, the conduction electrons localize only upon lithium ion insertion, thus rationalizing the two modes of optical switching observed in a single material. These multimodal electrochromic properties show promise for application in dynamic optical filters or smart windows.
authors.affiliation: †McKetta Department of Chemical Engineering, The University of Texas at Austin, 200 E. Dean Keeton Street, Austin, Texas 78712, United States.
authors.forename: Clayton J
authors.initials: CJ
authors.lastname: Dahlman
authors.affiliation: †McKetta Department of Chemical Engineering, The University of Texas at Austin, 200 E. Dean Keeton Street, Austin, Texas 78712, United States.
authors.forename: Yizheng
authors.initials: Y
authors.lastname: Tan
authors.forename: Matthew A
authors.initials: MA
authors.lastname: Marcus
authors.affiliation: †McKetta Department of Chemical Engineering, The University of Texas at Austin, 200 E. Dean Keeton Street, Austin, Texas 78712, United States.
authors.forename: Delia J
authors.initials: DJ
authors.lastname: Milliron