Generation of Enzymatic Hydrogen Peroxide to Accelerate the Etching of Silver Nanocrystals with Selectivity
Journal
Chemistry of Materials
Journal Volume
28
Journal Issue
20
Pages
7519-7527
Date Issued
2016
Author(s)
Abstract
We report a simple and versatile system for generating highly concentrated H2O2 on the surface of nanoparticles through enzymatic oxidation of glucose. It involves immobilization of glucose oxidase, a negatively charged enzyme, on the surface of a positively charged metal nanoparticle via electrostatic attraction. Upon the introduction of glucose at a concentration of 1.7 mM, this system is able to produce enzymatic H2O2 on the surface of the nanoparticle, with oxidation power equivalent to that of aqueous H2O2 at a concentration of 5 M when it is directly added into the reaction solution. We have evaluated the system for the etching of both twinned and single-crystal Ag nanocubes. We identified that the highly localized and concentrated H2O2 generated on the surfaces of Ag twinned cubes would lead to selective etching from the {111} facets parallel to the twin plane, in a fashion identical to the growth process but in the reversed order. For Ag single-crystals nanocubes, the etching would initiate from the corners to gradually transform the cubes into spheres. This study offers the opportunity to control the etching of metal nanocrystals with selectivity for elucidating the mechanism and diversifying the nanocrystals.
SDGs
Type
journal article