Effect of the fluid-wall interaction on freezing of confined fluids: Toward the development of a global phase diagram

We report molecular simulation studies of the freezing behavior of fluids in nano-porous media. The effect of confinement is to induce spatial constraints as well as energetic heterogeneity on the confined fluid, thereby altering the bulk phase behavior drastically. We consider the effect of the fluid-wall interaction energy on the shift of the freezing temperature and on the fluid structure, using a novel approach to calculate the free energy surface based on Landau theory and order parameter formulation. Corresponding states theory is then used to map out the global freezing behavior of a Lennard-Jones (LJ) fluid in model slit-shaped pores of varying fluid-wall interaction strengths. Using LJ parameters fitted to thermophysical property behavior, we predict the qualitative freezing behavior for a variety of fluids and nano-porous materials, based on a global freezing diagram. We have attempted to verify these predictions by comparing with experimental data for several systems, and show that in these cas...

[1]  H. Christenson.  Phase behaviour in slits—when tight cracks stay wet , 1997 .

[2]  C. F. Curtiss,et al.  Molecular Theory Of Gases And Liquids , 1954 .

[3]  E. M. Lifshitz,et al.  Statistical physics. Pt.1, Pt.2 , 1980 .

[4]  N. D. Mermin,et al.  Crystalline Order in Two Dimensions , 1968 .

[5]  D. Oxtoby.  New perspectives on freezing and melting , 1990, Nature.

[6]  K. Morishige,et al.  Freezing and melting of water in a single cylindrical pore: The pore-size dependence of freezing and melting behavior , 1999 .

[7]  T. Lubensky,et al.  Principles of condensed matter physics , 1995 .

[8]  K. Gubbins,et al.  A Remarkable Elevation of Freezing Temperature of CCl4 in Graphitic Micropores , 1999 .

[9]  J. Baker,et al.  Nucleation of Ice in Confined Geometry , 1997 .

[10]  U. Marconi,et al.  Phase equilibria and solvation forces for fluids confined between parallel walls , 1987 .

[11]  Daan Frenkel,et al.  New Monte Carlo method to compute the free energy of arbitrary solids. Application to the fcc and hcp phases of hard spheres , 1984 .

[12]  W. Steele.  The interaction of gases with solid surfaces , 1974 .

[13]  J. Banavar,et al.  Freezing in confined geometries , 1992 .

[14]  Daan Frenkel,et al.  Free energy changes on freezing and melting ductile metals , 1993 .

[15]  D. C. Bonner,et al.  Applied statistical mechanics, Thomas M. Reed and Keith E. Gubbins, McGraw‐Hill, New York (1973). 506 + xx pages. $18.50 , 1973 .

[16]  Krim,et al.  Triple-point wetting and surface melting of oxygen films adsorbed on graphite. , 1987, Physical review letters.

[17]  M. P. Allen,et al.  Monte Carlo studies of the freezing and condensation transitions of confined fluids , 1999 .

[18]  K. Gubbins,et al.  Phase Transitions in Pores: Experimental and Simulation Studies of Melting and Freezing† , 1999 .

[19]  K. Gubbins,et al.  Freezing/melting phenomena for Lennard-Jones methane in slit pores: A Monte Carlo study , 1997 .

[20]  K. Kaneko,et al.  Melting temperature elevation of benzene confined in graphitic micropores , 1999 .

[21]  Rahman,et al.  Characterization of porous solids by NMR. , 1993, Physical review letters.

[22]  Warnock,et al.  Geometrical supercooling of liquids in porous glass. , 1986, Physical review letters.

[23]  E. Kumacheva,et al.  Confinement-Induced Phase Transitions in Simple Liquids , 1995, Science.

[24]  K. Morishige,et al.  X-ray diffraction studies of freezing and melting of water confined in a mesoporous adsorbent (MCM-41) , 1997 .

[25]  Daan Frenkel,et al.  COMPUTER-SIMULATION STUDY OF FREE-ENERGY BARRIERS IN CRYSTAL NUCLEATION , 1992 .

[26]  K. Overloop,et al.  Freezing Phenomena in Adsorbed Water as Studied by NMR , 1993 .

[27]  Ravi Radhakrishnan,et al.  Freezing of simple fluids in microporous activated carbon fibers: Comparison of simulation and experiment , 1999 .

[28]  Seidel,et al.  Heat capacity and torsional oscillator studies of molecular hydrogen in porous Vycor glass. , 1990, Physical review. B, Condensed matter.

[29]  J. H. Cushman,et al.  Epitaxy in simple classical fluids in micropores and near-solid surfaces , 1987, Nature.

[30]  K. Gubbins,et al.  Characterization of Porous Glasses: Simulation Models, Adsorption Isotherms, and the Brunauer−Emmett−Teller Analysis Method , 1998 .

[31]  Chan,et al.  Freezing and melting of fluids in porous glasses. , 1993, Physical review. B, Condensed matter.

[32]  H. Maris,et al.  Specific heats of hydrogen, deuterium, and neon in porous Vycor glass , 1983 .

[33]  Andreas Stöcker,et al.  Low-Temperature Phase Transition of Water Confined in Mesopores Probed by NMR. Influence on Pore Size Distribution , 1996 .

[34]  Huber,et al.  Melting and freezing behavior of indium metal in porous glasses. , 1993, Physical review. B, Condensed matter.

[35]  William A. Steele,et al.  The physical interaction of gases with crystalline solids: I. Gas-solid energies and properties of isolated adsorbed atoms☆ , 1973 .

[36]  K. Gubbins,et al.  A molecular simulation study of freezing/melting phenomena for Lennard-Jones methane in cylindrical nanoscale pores , 1997 .

[37]  G. Torrie,et al.  Monte Carlo free energy estimates using non-Boltzmann sampling: Application to the sub-critical Lennard-Jones fluid , 1974 .

[38]  N. J. Wilkinson,et al.  Phase transitions of CO2 confined in nanometer pores as revealed by positronium annihilation , 1995 .

[39]  Ravi Radhakrishnan,et al.  FREE ENERGY STUDIES OF FREEZING IN SLIT PORES : AN ORDER-PARAMETER APPROACH USING MONTE CARLO SIMULATION , 1999 .