Adhesion and attraction heterogeneity introduced by manganese-oxide nanostructures on rhodochrosite

ENVR 106

Chongzheng Na, cnaz@seas.harvard.edu and Scot Martin, smartin@deas.harvard.edu. School of Engineering and Applied Sciences, Harvard University, 40 Oxford St., ESL 318, Cambridge, MA 02138
Rhodochrosite is important for the element cycles of manganese and carbon, the solution chemistry of natural waters, the immobilization of heavy metals and the biochemical interactions between minerals and microorganisms. The interaction of rhodochrosite with the environment can be varied by the formation of manganese-oxide nanostructures through the reaction with dissolved oxygen in aqueous solution. Using in situ force-volume atomic force microscopy (AFM), we found the nanostructures, compared to the rhodochrosite substrate, exhibited greater adhesion and attraction to a negatively charged silicon-nitride AFM tip in the electrolyte solution. These results suggest that the introduction of the nanostructures can promote the adsorption of anions and negatively-charged colloids while suppressing the adsorption of metal cations.
 

General Topics
2:00 PM-4:10 PM, Wednesday, August 22, 2007 Boston Park Plaza -- Beacon Hill Rm, Oral

Division of Environmental Chemistry

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007