title: A silica sol-gel design strategy for nanostructured metallic materials.
abstract: Batteries, fuel cells and solar cells, among many other high-current-density devices, could benefit from the precise meso- to macroscopic structure control afforded by the silica sol-gel process. The porous materials made by silica sol-gel chemistry are typically insulators, however, which has restricted their application. Here we present a simple, yet highly versatile silica sol-gel process built around a multifunctional sol-gel precursor that is derived from the following: amino acids, hydroxy acids or peptides; a silicon alkoxide; and a metal acetate. This approach allows a wide range of biological functionalities and metals--including noble metals--to be combined into a library of sol-gel materials with a high degree of control over composition and structure. We demonstrate that the sol-gel process based on these precursors is compatible with block-copolymer self-assembly, colloidal crystal templating and the Stöber process. As a result of the exceptionally high metal content, these materials can be thermally processed to make porous nanocomposites with metallic percolation networks that have an electrical conductivity of over 1,000 S cm(-1). This improves the electrical conductivity of porous silica sol-gel nanocomposites by three orders of magnitude over existing approaches, opening applications to high-current-density devices.
authors.affiliation: Department of Materials Science & Engineering, Cornell University, Ithaca, New York 14853, USA.
authors.forename: Scott C
authors.initials: SC
authors.lastname: Warren
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Perkins
authors.forename: Ashley M
authors.initials: AM
authors.lastname: Adams
authors.forename: Marleen
authors.initials: M
authors.lastname: Kamperman
authors.forename: Andrew A
authors.initials: AA
authors.lastname: Burns
authors.forename: Hitesh
authors.initials: H
authors.lastname: Arora
authors.forename: Erik
authors.initials: E
authors.lastname: Herz
authors.forename: Teeraporn
authors.initials: T
authors.lastname: Suteewong
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Sai
authors.forename: Zihui
authors.initials: Z
authors.lastname: Li
authors.forename: Jörg
authors.initials: J
authors.lastname: Werner
authors.forename: Juho
authors.initials: J
authors.lastname: Song
authors.forename: Ulrike
authors.initials: U
authors.lastname: Werner-Zwanziger
authors.forename: Josef W
authors.initials: JW
authors.lastname: Zwanziger
authors.forename: Michael
authors.initials: M
authors.lastname: Grätzel
authors.forename: Francis J
authors.initials: FJ
authors.lastname: DiSalvo
authors.forename: Ulrich
authors.initials: U
authors.lastname: Wiesner