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 (⁠|${\rm 10\bar 14}$|101¯4) surface are presented. This new AFM provides unprecedented in situ access to interfacial phenomena at solid–fluid interfaces under pressure.

1.
R. S.
Arvidson
,
M.
Collier
,
K. J.
Davis
,
M. D.
Vinson
,
J. E.
Amonette
, and
A.
Luttge
,
Geochim. Cosmochim. Acta
70
,
583
(
2006
).
2.
J.
Bisschop
,
D. K.
Dysthe
,
C. V.
Putnis
, and
B.
Jamtveit
,
Geochim. Cosmochim. Acta
70
,
1728
(
2006
).
3.
P. M.
Dove
and
F. M.
Platt
,
Chem. Geol.
127
,
331
(
1996
).
4.
G.
Jordan
and
W.
Rammensee
,
Geochim. Cosmochim. Acta
62
,
941
(
1998
).
5.
A. S.
Lea
,
J. E.
Amonette
,
D. R.
Baer
,
Y.
Liang
, and
N. G.
Colton
,
Geochim. Cosmochim. Acta
65
,
369
(
2001
).
6.
A. S.
Lea
,
T. T.
Hurt
,
A.
El-Azab
,
J. E.
Amonette
, and
D. R.
Baer
,
Surf. Sci.
524
,
63
(
2003
).
7.
Y.
Liang
,
A. S.
Lea
,
D. R.
Baer
, and
M. H.
Engelhard
,
Surf. Sci.
351
,
172
(
1996
).
8.
S. L. S.
Stipp
,
C. M.
Eggleston
, and
B. S.
Nielsen
,
Geochim. Cosmochim. Acta
58
,
2023
(
1994
).
9.
H. H.
Teng
,
Geochim. Cosmochim. Acta
68
,
253
(
2004
).
10.
M.
Xu
,
X.
Hu
,
K. G.
Knauss
, and
S. R.
Higgins
,
Geochim. Cosmochim. Acta
74
,
4285
(
2010
).
11.
A. J.
Gratz
,
S.
Manne
, and
P. K.
Hansma
,
Science
251
,
1343
(
1991
).
12.
S. V.
Yanina
,
K. M.
Rosso
, and
P.
Meakin
,
Geochim. Cosmochim. Acta
70
,
1113
(
2006
).
13.
G.
Jordan
,
S. R.
Higgins
, and
C. M.
Eggleston
,
American Mineralogist
84
,
144
(
1999
).
14.
S. R.
Higgins
and
X.
Hu
,
Geochim. Cosmochim. Acta
69
,
2085
(
2005
).
15.
S. R.
Higgins
,
C. M.
Eggleston
,
K. G.
Knauss
, and
C. O.
Boro
,
Rev. Sci. Instrum.
69
,
2994
(
1998
).
16.
S. R.
Higgins
,
G.
Jordan
, and
C. M.
Eggleston
,
Geochim. Cosmochim. Acta
66
,
3201
(
2002
).
17.
G.
Jordan
,
S. R.
Higgins
,
C. M.
Eggleston
,
K. G.
Knauss
, and
W. W.
Schmael
,
Geochim. Cosmochim. Acta
65
,
4257
(
2001
).
18.
G. D.
Saldi
,
G.
Jordan
,
J.
Schott
, and
E. H.
Oelkers
,
Geochim. Cosmochim. Acta
73
,
5646
(
2009
).
19.
S. R.
Higgins
,
D.
Bosbach
,
C. M.
Eggleston
, and
K. G.
Knauss
,
J. Phys. Chem. B
104
,
6978
(
2002
).
20.
G.
Jordan
,
S. R.
Higgins
,
C. M.
Eggleston
,
S. M.
Swapp
,
D. M.
Janney
, and
K. G.
Knauss
,
Geochim. Cosmochim. Acta
63
,
3183
(
1999
).
21.
K.
Aldushin
,
G.
Jordan
, and
W. W.
Schmahl
,
Geochim. Cosmochim. Acta
70
,
4380
(
2006
).
22.
H.
Shao
,
J. R.
Ray
, and
Y.-S.
Jun
,
Environ. Sci. Technol.
44
,
5999
(
2010
).
23.
M.
Sorai
,
T.
Ohsumi
, and
M.
Ishikawa
,
Energy
30
,
2334
(
2005
).
24.
G.
Jordan
and
J. M.
Astilleros
,
Am. Mineral.
91
,
619
(
2006
).
25.
R.
Span
and
W.
Wagner
,
J. Phys. Chem. Ref. Data
25
,
1509
(
1996
).
26.
H.
Tang
,
E.
Gulari
, and
E. W.
Rothe
,
J Supercrit. Fluids
18
,
193
(
2000
).
27.
W. J.
Tropf
and
M. E.
Thomas
, in
Handbook of Optical Constants of Solids III
, edited by
E. D.
Palik
(
Academic
,
San Diego
,
1998
), p.
651
.
28.
W. L.
Bourcier
and
H. L.
Barnes
, in
Hydrothermal Experimental Methods
, Edited by
G. C.
Ulmer
and
H. L.
Barnes
(
Wiley
,
New York
,
1987
), p.
189
.
29.
W. E.
Seyfried
,
D. R.
Janecky
, and
M. E.
Berndt
, in
Hydrothermal Experimental Methods
, edited by
G. C.
Ulmer
and
H. L.
Barnes
(
Wiley
,
New York
,
1987
).
30.
M. W.
Hooker
, NASA/CR-1998–208708v, (
1998
).
31.
T. A.
Kendall
and
S. A.
Martin
,
J. Phys. Chem. A
111
,
505
(
2007
).
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