A high-pressure atomic force microscope for imaging in supercritical carbon dioxide

Journal Article · Tue Apr 26 00:00:00 EDT 2011 · Review of Scientific Instruments, 82(4):Article No.: 043709

DOI:https://doi.org/10.1063/1.3580603· OSTI ID:1012855

Lea, Alan S; Higgins, Steven R; Knauss, Kevin G; Rosso, Kevin M

A high-pressure atomic force microscope (AFM) that enables in-situ, atomic scale measurements of topography of solid surfaces in contact with supercritical CO2 (scCO2) fluids has been developed. This apparatus overcomes the pressure limitations of the hydrothermal AFM and is designed to handle pressures up to 100 atm at temperatures up to ~ 350 K. A standard optically-based cantilever deflection detection system was chosen. When imaging in compressible supercritical fluids such as scCO2, precise control of pressure and temperature in the fluid cell is the primary technical challenge. Noise levels and imaging resolution depend on minimization of fluid density fluctuations that change the fluid refractive index and hence the laser path. We demonstrate with our apparatus in-situ atomic scale imaging of a calcite (CaCO3) mineral surface in scCO2; both single, monatomic steps and dynamic processes occurring on the (10¯14) surface are presented. This new AFM provides unprecedented in-situ access to interfacial phenomena at solid-fluid interfaces under pressure.

• Research Organization: Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Environmental Molecular Sciences Lab. (EMSL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1012855
• Report Number(s): PNNL-SA-77820; 39924; 40896; 32092; KP1704020; TRN: US1102380
• Journal Information: Review of Scientific Instruments, 82(4):Article No.: 043709, Vol. 82, Issue 4; ISSN 0034-6748
• Country of Publication: United States
• Language: English

Related Subjects

12 MANAGEMENT OF RADIOACTIVE WASTES, AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
CALCITE
CARBON DIOXIDE
DETECTION
FLUCTUATIONS
LASERS
MICROSCOPES
MINIMIZATION
REFRACTIVE INDEX
RESOLUTION
TOPOGRAPHY
high
pressure
atomic
force
microscope
imaging
supercritical
carbon
dioxide
Environmental Molecular Sciences Laboratory