• Disalvo, Francis J.
• Warren, Scott C.
• Arora, Hitesh
• Sai, Hiroaki
• Zwanziger, Josef W.
• Adams, Ashley M.
• Werner, Jörg
• Perkins, Matthew R.
• Grätzel, Michael
• Song, Juho
• Werner-Zwanziger, Ulrike
• Burns, Andrew A.
• Wiesner, Ulrich
• Kamperman, Marleen
• Herz, Erik
• Li, Zihui
• Suteewong, Teeraporn

Abstract

<p>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.</p>

Topics

• porous
• nanocomposite
• density
• impedance spectroscopy
• Silicon
• copolymer
• electrical conductivity
• self-assembly
• Stöber process