Sintering of titanium dioxide nanoparticles: a comparison between molecular dynamics and phenomenological modeling

Molecular dynamics simulations were used to determine the melting points of anatase and rutile nanoparticles. The melting points decrease with decrease in particle diameter and are in reasonable agreement with the empirical formula derived by Buffat and Borel. The phenomenological model of Koch and Friedlander is unable to predict the temperature rise during initial stages of sintering with acceptable accuracy. It is argued that the Koch and Friedlander assumption of linear surface reduction rate upon sintering may be inadequate for the time scales under consideration. A theoretical model using direct area measurement from molecular dynamics simulations and a single adjustable parameter is able to predict temperature rise during initial stages of sintering within acceptable error limits.

[1]  A. Franks.  REVIEW ARTICLE: Nanotechnology , 1987 .

[2]  P. Cummings,et al.  Molecular dynamics simulation of titanium dioxide nanoparticle sintering. , 2005, The journal of physical chemistry. B.

[3]  A. Romig.  Nanotechnology: Scientific challenges and societal benefits and risks , 2004 .

[4]  Gabriel A Silva,et al.  Introduction to nanotechnology and its applications to medicine. , 2004, Surgical neurology.

[5]  L. Curtiss,et al.  Modeling the Morphology and Phase Stability of TiO2 Nanocrystals in Water. , 2005, Journal of chemical theory and computation.

[6]  K. Lehtinen,et al.  Effect of coalescence energy release on the temporal shape evolution of nanoparticles , 2001 .

[7]  S. R. Mehr,et al.  Rapid assessment of TiO2 pigment durability via the acid solubility test , 2004 .

[8]  Richard W. Siegel,et al.  Exploring Mesoscopia: The Bold New World of Nanostructures , 1993 .

[9]  A. Gavezzotti,et al.  Molecular free surface: a novel method of calculation and its uses in conformational studies and in organic crystal chemistry , 1985 .

[10]  Masanori Matsui,et al.  Molecular Dynamics Simulation of the Structural and Physical Properties of the Four Polymorphs of TiO2 , 1991 .

[11]  P. C. Clapp,et al.  Nanoparticle sintering simulations , 1998 .

[12]  J. Justin Gooding,et al.  Nanostructuring electrodes with carbon nanotubes: A review on electrochemistry and applications for sensing , 2005 .

[13]  R. German.  Sintering theory and practice , 1996 .

[14]  S. Pratsinis,et al.  Competition between gas phase and surface oxidation of TiCl4 during synthesis of TiO2 particles , 1998 .

[15]  P. Buffat,et al.  Size effect on the melting temperature of gold particles , 1976 .

[16]  Michael R. Zachariah,et al.  Energy accumulation in nanoparticle collision and coalescence processes , 2002 .

[17]  S. Sahoo,et al.  Nanotech approaches to drug delivery and imaging. , 2003, Drug discovery today.

[18]  B.A. Oakley,et al.  A review of nanobioscience and bioinformatics initiatives in North America , 2004, IEEE Transactions on NanoBioscience.

[19]  Y. Aoyagi,et al.  Carbon nanotube devices for nanoelectronics , 2002 .

[20]  M. Zachariah,et al.  Molecular Dynamics Computation of Gas-Phase Nanoparticle Sintering: A Comparison with Phenomenological Models , 1999 .

[21]  Xing Ding,et al.  Grain growth enhanced by anatase-to-rutile transformation in gel-derived nanocrystalline titania powders , 1997 .

[22]  D. Dingwell,et al.  The Density of Titanium(IV) Oxide Liquid , 1991 .

[23]  Sotiris E. Pratsinis,et al.  Vapor synthesis of titania powder by titanium tetrachloride oxidation , 1991 .

[24]  Ya-li Li,et al.  Thermodynamic analysis of nucleation of anatase and rutile from TiO2 melt , 2002 .

[25]  D. E. Rosner,et al.  Prediction of Spherule Size in Gas Phase Nanoparticle Synthesis , 1999 .

[26]  Sotiris E. Pratsinis,et al.  Flame aerosol synthesis of ceramic powders , 1998 .

[27]  Sotiris E. Pratsinis,et al.  Aerosol flame reactors for manufacture of nanoparticles , 2002 .

[28]  R. Nieminen,et al.  Effect of potential energy distribution on the melting of clusters. , 2001, Physical review letters.

[29]  B. Ohtani,et al.  Photocatalytic activity of titania powders suspended in aqueous silver nitrate solution: correlation with pH-dependent surface structures , 1987 .

[30]  O. Preining.  The physical nature of very, very small particles and its impact on their behaviour , 1998 .

[31]  Katsuki Kusakabe,et al.  Growth and transformation of TiO2 crystallites in aerosol reactor , 1991 .

[32]  A. Tanenbaum.  Computer recreations , 1973 .

[33]  R. Nieminen,et al.  Universal melting behaviour of clusters , 2001 .

[34]  A. Y. Meyer.  Molecular mechanics and molecular shape. V. on the computation of the bare surface area of molecules , 1988 .

[35]  K. Lehtinen,et al.  Structure and Properties of Silica Nanoclusters at High Temperatures , 2002 .

[36]  A. Bondi.  van der Waals Volumes and Radii , 1964 .

[37]  W. Koch,et al.  The effect of particle coalescence on the surface area of a coagulating aerosol , 1990 .

[38]  William Smith,et al.  CCP5: a collaborative computational project for the computer simulation of condensed phases , 1987 .

[39]  Wu,et al.  Linear rate law for the decay of the excess surface area of a coalescing solid particle. , 1994, Physical review. B, Condensed matter.

[40]  C. Ao,et al.  Indoor air purification by photocatalyst TiO2 immobilized on an activated carbon filter installed in an air cleaner , 2005 .

[41]  M. Fujihira,et al.  Heterogeneous photocatalytic oxidation of aromatic compounds on TiO2 , 1981, Nature.

[42]  B. Singaraju,et al.  Nanotechnology in aerospace systems , 2003 .

[43]  Akbar Nayeem,et al.  MSEED: A program for the rapid analytical determination of accessible surface areas and their derivatives , 1992 .

[44]  M. Karplus,et al.  The distance fluctuation criterion for melting: Comparison of square-well and Morse potential models for clusters and homopolymers , 2002 .

[45]  P. Sanders,et al.  Residual stress, strain and faults in nanocrystalline palladium and copper , 1995 .

[46]  B. Berne.  Energy accommodation in collisions of small particles , 1986 .

[47]  A. Laaksonen,et al.  The effect of ions on solid–liquid phase transition in small water clusters. A molecular dynamics simulation study , 2003 .

[48]  S. Alavi,et al.  Molecular dynamics simulations of the melting of aluminum nanoparticles. , 2006, The journal of physical chemistry. A.

[49]  W Smith,et al.  DL_POLY_2.0: a general-purpose parallel molecular dynamics simulation package. , 1996, Journal of molecular graphics.

[50]  H. Jang,et al.  The Effects of Temperature on Particle Size in the Gas-Phase Production of TiO2 , 1995 .

[51]  M. Karplus,et al.  Native proteins are surface-molten solids: application of the Lindemann criterion for the solid versus liquid state. , 1999, Journal of molecular biology.

[52]  J. Lemaire,et al.  Influence of titanium dioxide pigment characteristics on durability of four paints (acrylic isocyanate, polyester melamine, polyester isocyanate, alkyd) , 1997 .

[53]  S. Friedlander,et al.  Characteristics of SiO2/TiO2 nanocomposite particles formed in a premixed flat flame , 1998 .

[54]  M. Karplus,et al.  Folding thermodynamics of a model three-helix-bundle protein. , 1997, Proceedings of the National Academy of Sciences of the United States of America.

[55]  G. Rohrer,et al.  Orientation Dependence of Photochemical Reactions on TiO2 Surfaces , 1998 .

[56]  Molecular dynamics simulations of solid–liquid phase transition in small water aggregates , 2006 .

[57]  J. Banfield,et al.  Thermodynamic analysis of phase stability of nanocrystalline titania , 1998 .

[58]  Kenneth M. Merz,et al.  Rapid approximation to molecular surface area via the use of Boolean logic and look‐up tables , 1993, J. Comput. Chem..

[59]  A. Laaksonen,et al.  Solid-liquid phase transition in small water clusters: a molecular dynamics simulation study , 2002 .

[60]  H. Jang.  Effects of H2O on the particle size in the vapor‐phase synthesis of TiO2 , 1997 .

[61]  A. Y. Meyer.  Molecular mechanics and molecular shape: Part VII. Structural factors in the estimation of solvation energies , 1985 .

[62]  S. Hara,et al.  Surface Tensions and Densities of Molten Al2O3, Ti2O3, V2O5 and Nb2O5. , 1993 .

[63]  M. Zachariah,et al.  Internal pressure and surface tension of bare and hydrogen coated silicon nanoparticles. , 2004, The Journal of chemical physics.

[64]  M. Karplus,et al.  Equilibrium thermodynamics of homopolymers and clusters: Molecular dynamics and Monte Carlo simulations of systems with square-well interactions , 1997 .

[65]  H. Akbari,et al.  Solar spectral optical properties of pigments—Part II: survey of common colorants , 2004 .

[66]  M. Hoffmann,et al.  Chemical mechanism of inorganic oxidants in the TiO2/UV process: increased rates of degradation of chlorinated hydrocarbons. , 1995, Environmental science & technology.