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Multi-Scale Simulations of the Growth and Assembly of Colloidal Nanoscale Materials

Kristen A. Fichthorn Department of Chemical Engineering Department of Physics Penn State University. Multi-Scale Simulations of the Growth and Assembly of Colloidal Nanoscale Materials. DE-FG0207ER46414. Complex Nanostructures in Colloidal Crystal Growth: How Do They Form?.

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Multi-Scale Simulations of the Growth and Assembly of Colloidal Nanoscale Materials

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  1. Kristen A. Fichthorn Department of Chemical Engineering Department of Physics Penn State University Multi-Scale Simulations of the Growth and Assembly of Colloidal Nanoscale Materials DE-FG0207ER46414

  2. Complex Nanostructures in Colloidal Crystal Growth: How Do They Form? Cluster-Cluster Aggregation Ostwald Ripening Oriented Attachment How Does OA Happen?

  3. Oriented Attachment and the Mesocrystal State: The Role of Solvent Oriented Attachment of TiO2: Intrinsic Crystal Forces Complex Nanostructures in Colloidal Crystal Growth: Oriented Attachment V. Yuwano, N. Burrows, J. Soltis, and R. Penn, JACS 132, 2163 (2010). R. Penn and J. Banfield, Geochim. Cosmochim. Acta63, 1549 (1999). M. Alimohammadi and K. Fichthorn, Nano Lett. 9, 4198 (2009).

  4. Complex Nanostructures in Colloidal Crystal Growth: Capping Agents Y. Sun, B. Mayers, T. Herricks, and Y. Xia, Nano Lett. 3, 955 (2003).

  5. “One-Pot” Solution-Phase Synthesis of Nanostructured Metal Materials • Polyol Process • Solvent: Ethylene Glycol • Salt: AgNO3 • “Stabilizer”: PVP • N,N-DMF Reduction • Solvent: N,N-DMF • Salt: AgNO3 • “Stabilizer”: PVP All Kinds of Nano-Shapes Heat at ~400 K What Happens in the Pot? B. Wiley,…Y. Xia, Chem. Eur. J. 11, 454 (2005).

  6. Nanostructure Formation: General Aspects Seed Formation Growth Reduction of Ag Nucleation Determined by Salt and… Solvent or PVP? Probably Determined by PVP… B. Wiley,…Y. Xia, Chem. Eur. J. 11, 454 (2005).

  7. One Possible Role of PVP: Surface-Sensitive Binding Y. Sun, B. Mayers, T. Herricks, and Y. Xia, Nano Lett. 3, 955 (2003). Nanocubes from Single- Crystal Cubo-Octahedral Seeds Nanowires from Multiply- Twinned Decahedral Seeds G. Grochola, I. Snook, and S. Russo, J. Chem. Phys. 127, 194707 (2007). Does PVP Prefer Ag(100) Over Ag(111)?

  8. Interaction of PVP with Ag(100) and Ag(111):First-Principles Challenges L. DelleSite, K. Kremer, Int. J. Quant. Chem. 101, 733 (2005). vdW Direct Bonding + van der Waals (vdW) Coarse-Grained Model n Historically DFT Described Direct Bonds, Including vdW Interactions is New… S. Grimme, J. Comput. Chem. 27, 1787 (2006). M. Dion,…, D. C. Langreth, B. I. Lundqvist, Phys. Rev. Lett. 92, 246401 (2004). A. Tkatchenko and M. Scheffler, Phys. Rev. Lett. 102, 073005 (2009).K. Lee, …, D. C. Langreth, B. I. Lundqvist, Phys. Rev. B 82, 081101 (2010).

  9. Interaction of PVP with Ag(100) and Ag(111): VASP 5.2.11 • (4×4×14) Super Cell • Slab: 6 layers • Vacuum: 8 layers • PAW-PBE (GGA) ± DFT-D2 ± TS* • Assess the Influence of • vdW Interactions • Cut-off: 29.4 Ry • k-points: (4×4×1) • Ab-initio Molecular Dynamics • Static Total-Energy Calculations *Implemented in VASP by Wissam Al-Saidi

  10. van der Waals Interactions in DFT: How Do We Describe Ag?? aS. Grimme, J. Comput. Chem. 27, 1787 (2006). bA. Tkatchenko and M. Scheffler, Phys. Rev. Lett. 102, 073005 (2009) . cE. Zaremba and W. Kohn, Phys. Rev. B 13, 2279 (1976). dS. Eichenlaub, C. Chan, and S. P. Beaudoin, J. Coll. Int. Sci. 248, 389 (2002). eA.Khein, D. J. Singh, and C. J. Umrigar, Phys. Rev. B 51, 4105, (1995). fH. Li, et al., Phys. Rev. B 43, 7305 (1991). gF. R. De Boer, et al., Cohesion in Metals, Amsterdam, (1988). hM.Chelvayohan and C.H.B. Mee, J. Phys. C: Solid State Phys.15, 2305 (1982).

  11. Binding Conformations:No vdW Interactions Top Top Bridge Hollow fcc Hollow Trial & Error: Bonding with O Atom Down Ag(100) hcp Hollow Bridge Ag(111) Experimental IR and XPS: PVP Binds to Ag via the O and/or N Atom. F. Bonetet al., Bull. Mater. Sci. 23, 165 (2000). Z. Zhang et al., J. Solid State Chem. 121, 105 (1996). H. H. Huang et al., Langmuir 12, 909 (1996).

  12. Binding Energies: No vdW Interactions Top Top Bridge Hollow fcc Hollow • Bond Strength (eV) Ag(100) hcp Hollow Bridge Ag(111) • Predominantly vdW Preference for Ag(111): Contrary to Expectations Ethane Binds: X.-L. Zhou and J. M. White, J. Phys. Chem. 96, 7703 (1992).

  13. vdW Interactions Support Structure-Directing Hypothesis • Bond Strength (eV) Why Such Big Differences Between Methods??

  14. DFT-D2: Ag(100) Reconstructs Ag(100) Reconstruction has not been Observed Experimentally…

  15. TS+ZK:2-Pyrrolidone on Ag(100) Top || Ebind= 0.78 Bridge Ebind= 0.77 Hollow Ebind= 0.59 Top Ebind= 0.60 Lots of Options! Binding via O and N F. Bonetet al., Bull. Mater. Sci. 23 (2000). Z. Zhang et al., J. Solid State Chem. 121 (1996). H. H. Huang et al., Langmuir 12 (1996). Bridge || Ebind= 0.81 Hollow || Ebind= 0.77

  16. PVP ~139 Times More Likely to Bind to Ag(100) “Sides” than Ag(111) “Ends”

  17. TS+ZK Method: Break-Down of Binding Energy

  18. TS+ZK Method: Break-Down of Binding Energy Ag(100): vdW and Direct Bonding Synergize

  19. TS+ZK Method: Break-Down of Binding Energy Ag(111): vdW is the Dominant Attractive Force Sometimes the only Attractive Force

  20. Conclusions • We Studied Surface-Sensitivity of • PVP Binding to Ag(111) and Ag(100) • We Observed Stronger Binding to • Ag(100) when we Include vdW • As Inferred by Experiment • DFT-D2 Reconstructs Ag(100) • Ag(100) Preference from Synergy Between • vdW Attraction and Direct Bonding

  21. HRTEM: Oriented Attachment of TiO2 Nanoparticles R. Penn and J. Banfield, Geochim. Cosmochim. Acta63, 1549 (1999). OrientedAttachmentin Crystal Growth: Role of Intrinsic Crystal Forces See Also: M. Niederberger and H. Cölfen, Phys. Chem. Chem. Phys. 8, 3271 (2006). Q. Zhang, S. Liu, and S. Yu, J. Mater. Chem. 19, 191 (2009).

  22. Dipole-Dipole Interactions May Assemble Nanoparticles + - + - T. Zhang, N. Kotov, and S. Glotzer, Nano Lett. 7, 1670 (2007). Z. Tang and N. Kotov, Adv. Mater. 17, 951 (2005); Z. Tang, N. Kotov, M. Giersig, Science 297, 237 (2002). CdTe Nanoparticle Chains

  23. TiO2 (Anatase) Nanocrystals Matsui-Akaogi Force Field Mol. Sim. 6, 239, 1991. * m=250 D (112) Truncated Nanocrystals m=75 D m=0 Two Wulff Nanocrystals (001) Truncated Nanocrystals m=35 D

  24. Aggregation of Wulff Nanocrystals

  25. Nanocrystal Aggregation: The Hinge Mechanism Initial Contact of Edges: The “Hinge” Rotation About the “Hinge”

  26. Nanocrystal Aggregation: Driven by Electrostatic Forces M. Alimohammadi and K. Fichthorn, Nano Lett. 9, 4198 (2009).

  27. Nanocrystal Aggregation: Driven by Multipoles from Under-Coordinated Surface Atoms M. Alimohammadi and K. Fichthorn, Nano Lett. 9, 4198 (2009).

  28. Simulation vs. Experiment: Still Have a Way to Go HRTEM Image Showing Oriented Attachment of 5 TiO2 Nanoparticles R. Penn and J. Banfield, Geochim. Cosmochim. Acta63, 1549 (1999). Aqueous Environment Hour (or longer) Times Vacuum Environment Nanosecond Times

  29. Conclusions Nanocrystal Aggregation is Driven by Local Interactions. We Should Re-Think the Dipole Idea… P. Schapotschnikowet al., Nano Lett. 10, 3966 (2010). Also found this for capped and uncapped PbSe…

  30. 1D Nanostructures form via Mesocrystals and Oriented Attachment Goethite Nanowires V. Yuwano, …, and R. Penn, JACS 132, 2163 (2010). Ag Nanowires M. Giersig, I. Pastoriza-Santos, L. Liz-Marzan, J. Mater. Chem. 14, 607 (2004).

  31. Solvent Ordering and Solvation Forces Solvent Density Profile Solvent ordering around solvophilic nanoparticles • Y. Qin and K. A. Fichthorn, J. Chem. Phys. 119, 9745 (2003). • Y. Qin and K. A. Fichthorn, Phys. Rev. E73, 020401 (2006).

  32. MD: Aggregation of a Small, Isotropic* Crystal with a Larger, Anisotropic Crystal Rectangular Cuboid Square Plate ● Generic Anisotropic fcc Nanoparticles ● Solvophilic Nanoparticles ● Strong vdW Attraction (Ag) ● Isotropic Organic Solvent 2 1 3 2 1 *Relatively

  33. Aggregation of Small and Large Nanocrystals: Mesocrystal States Mesocrystal State 1 One Solvent Layer Mesocrystal State 2 Two Solvent Layers Mesocrystal State 1 One Solvent Layer

  34. Aggregation of Small and Large Nanocrystals: Mesocrystal States Mesocrystal States: Free-Energy Minima Escape-Time Distribution Aggregation Probability Mesocrystal State 1 One Solvent Layer Mesocrystal State 2 Two Solvent Layers Mesocrystal State 1 One Solvent Layer

  35. Nanocrystal Encounters: Frequency of Outcomes Aggregation is the Most Frequent On the Smallest Facets, Perpetuating 1D Growth Aggregation: Fastest at End of Rectangle Slowest on Face of Square Even on Sides Mesocrystal State 1 Most Frequent Mesocrystal State 2 Occurs on Square Mesocrystal State 3 Dissociation Not Typically Frequent 3 1 2 1 2 Dissociation

  36. Disruption Solvent Ordering at Edges Leads to Fast Aggregation on Small Facets r/rb 7.2 6.6 6.0 5.4 4.8 4.2 3.6 3.0 2.4 1.8 1.2 0.6 0 Rectangle Rectangle Square Plate

  37. Conclusions Solvent Ordering Around Nanocrystal Surfaces Promotes Growth of 1D Nanostructures Leads to Mesocrystal States Faster Aggregation on Smaller Facets

  38. Collaborators Alums Dr. Yong Qin Dr. Rajesh Sathiyanarayanan Dr. LeonidasGergidis Fritz Haber Institute Alexander Tkatchenko Victor Gonzalo Ruiz Lopez Matthias Scheffler Univ. of Pittsburgh Dr. Wissam Al-Saidi Mozhgan Alimohammadi Haijun Feng Azar Shahraz Jin Pyo Hong Dr. Ya Zhou Dr. Yangzheng Lin Funding NSFDMR-1006452,NIRT CCR-0303976, CBET-0730987 DOE DE-FG0207ER46414 ACS, EPA, NCSA

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