Multi-Resolution Structure and Reactivity of Kinetically
Roughened Oxide Surfaces: Nanometric Scaling Behavior
and Molecular-Scale Controls (Rosso BES,PNNL Scope #43862. Rosso BES)
EMSL Project ID
4198
Abstract
Surfaces of Fe oxides, Mn oxides and Si oxides (quartz) minerals in natural settings exhibit a significant degreeof morphological heterogeneity on scales from 1-1000 nm. Surface roughness and its timedependent
evolution are important factors in growth, dissolution, and adsorption experiments,
but the relationships between these processes and roughness have not lent themselves to easy
quantification because of their inherent complexity. Furthermore, roughness can influence
surface reactivity in a manner which is distinctly different from simple surface area arguments
because it has a length scale dependence spread throughout the microscopic to mesoscopic
observation scales. Many tools have been developed recently that allow for an entirely new
strategy to quantitatively treat the evolution of irregularities on surfaces, one in which the
complexity is embraced and the dynamics are characterized wholesale. We propose that a
combination of scanning probe microscopy, scaling concepts, XPS, statistical image processing,
kinetic roughening theory, and atomistic modeling will outlay a important advance in this
difficult area. Using a close coupling of multi- scale microscopic observations and simulation,
we will quantitatively characterize the scaling behaviors of the dissolution of a series of
important low index surfaces of Fe and Mn oxides from the molecular-scale up to the
mesoscale regime. The structural contrast between the various surfaces and the ability of
these minerals to be dissolved by various mechanisms provides a unique opportunity to relate
roughness evolution to molecular-scale surface chemistry. Quantification of the dynamic
evolution of these surfaces will produce new fundamental insights into the dissolution
processes at the molecular-scale and identify processes that have an important impact across
observation length scales.
Project Details
Project type
Exploratory Research
Start Date
2003-10-01
End Date
2007-06-03
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members
Related Publications
Rosso KM, and M Dupuis. 2004. "Reorganization Energy Associated with Small Polaron Mobility in Iron Oxide." Journal of Chemical Physics 120(15):7050-7054.
Rosso KM, D Smith, and M Dupuis. 2004. "Aspects of aqueous iron and manganese (II/III) self-exchange electron transfer reactions." Journal of Physical Chemistry A 108(24):5242-5248.