Improving diffusion of water molecules in slits of titanium dioxide: molecular dynamics simulation

doi:10.3969/j.issn.0438-1157.2013.01.043

Abstract

Abstract: Titanium dioxide(TiO₂)materials are expected to play an important role in helping to solve many serious environmental and pollution challenges, because of their excellent performance in the fields of photocatalysis, biomaterials, electrochemistry and industrial catalysis.Among all the applications of TiO₂ materials, there is a common process which is the contact of water molecules with TiO₂ materials.Thus, the surface structure of TiO₂, especially micro-structure of water molecules on TiO₂ surface, plays a key role in the applications.Moreover, since the TiO₂ material with larger surface area performs better, preparation of TiO₂ materials with nanoporous structures has become a research direction.Hence, the behavior of water molecules confined in the nanopores of TiO₂ is one of hot topics.Literature and our previous research showed that water molecules strongly adsorbed on the TiO₂ surface, and the strong adsorption hindered the mobility of water molecules in the TiO₂ pores.In this work we intended to improve the mobility of water molecules confined in TiO₂ pores by molecular dynamics studies, and to explain the reasons for the increase of mobility.These results could help experimental researchers to understand and reschedule their experiments.By adjusting a number of simulation parameters, we proposed that the more reliable method was covering the surface of TiO₂ with a carbon layer.This method could greatly improve the mobility of water molecules in the TiO₂ pores without altering the original experimental condition.

Key words: titanium dioxide, molecular simulation, diffusion, interface, water, carbon, cover

摘要： 众所周知,二氧化钛(TiO₂)材料在光催化材料、生物材料、电化学和工业催化等多个领域表现出优异的性能,因而其在解决能源和环境危机中被寄予厚望。在上述TiO₂材料的众多应用中往往都离不开水分子与TiO₂材料的接触。TiO₂表面结构,特别是水分子在TiO₂表面上形成的微结构往往对于TiO₂材料的应用起到关键作用。另一方面,大比表面积的TiO₂材料表现出性能上的优势,因此制备具有纳米孔道结构的TiO₂材料成为研究趋势。结合上述两点,水分子受限于TiO₂纳米孔道中的行为成为研究的热点之一。以往的研究结果表明,水分子在TiO₂表面具有强吸附作用,而该作用会影响到水分子在TiO₂孔道中的流动性。本文意在通过分子模拟的研究,找到提高水分子TiO₂孔道中扩散性的方法,并解释流动性增加的原因,为实验研究工作者们提供指导和解释。通过调整多项模拟参数,结果表明对于实验工作更为可靠的方法是用碳层覆盖TiO₂的表面。这样可以在不改变原有实验条件的基础上大大提高水分子在TiO₂孔道中的扩散性。

关键词: 二氧化钛, 分子模拟, 扩散, 界面, 水分子, 碳, 覆盖

CLC Number:

TQ015.9

WEI Mingjie, LV Linghong, ZHU Yudan, GUO Xiaojing, LU Xiaohua. Improving diffusion of water molecules in slits of titanium dioxide: molecular dynamics simulation[J]. CIESC Journal, 2013, 64(1): 365-373.

魏明杰, 吕玲红, 朱育丹, 郭晓静, 陆小华. 提高二氧化钛孔道中水分子扩散性的分子模拟[J]. 化工学报, 2013, 64(1): 365-373.

References 48

[1]	Diebold U.The surface science of titanium dioxide[J].Surface Science Reports, 2003,48(5-8):53-229
[2]	Chen X, Mao S S.Titanium dioxide nanomaterials:synthesis, properties, modifications, and applications[J].Chemical Reviews, 2007,107(7):2891-2959
[3]	Fujishima A, Zhang X, Tryk D A.TiO2 photocatalysis and the related surface phenomena[J].Surface Science Reports, 2008,63:515-582
[4]	Selloni A, Vittadini A, Grtzel M.The adsorption of small molecules on the TiO2 anatase(101)surface by first-principles molecular dynamics[J].Surface Science, 1998,402-404:219-222
[5]	Michael A H.A surface science perspective on photocatalysis[J].Surface Science Reports, 2011,66(6/7):185-297
[6]	Gelb L D, Gubbins K E, Radhakrishnan R, Sliwinska-Bartkowiak M.Phase separation in confined systems[J].Reports on Progress in Physics, 1999,62(12):1573-1659
[7]	Bagchi B.Water dynamics in the hydration layer around proteins and micelles[J].Chemical Reviews, 2005,105(9):3197-3219
[8]	Cummings P T, Docherty H, Iacovella C R,Singh J K. Phase transitions in nanoconfined fluids:the evidence from simulation and theory[J].AIChE Journal, 2010,56(4):842-848
[9]	Wang J, Zhu Y, Zhou J, Lu X H.Diameter and helicity effects on static properties of water molecules confined in carbon nanotubes[J].Physical Chemistry Chemical Physics, 2004,6(4):829-835
[10]	Huang L, Shao Q, Lu L, Lu X, Zhang L, Wang J, Jiang S. Helicity and temperature effects on static properties of water molecules confined in modified carbon nanotubes[J].Physical Chemistry Chemical Physics, 2006,8(33):3836-3844
[11]	Huang L, Zhang L, Shao Q, Wang J, Lu L, Lu X, Jiang S, Shen W.Molecular dynamics simulation study of the structural characteristics of water molecules confined in functionalized carbon nanotubes[J].The Journal of Physical Chemistry B, 2006,110(51):25761-25768
[12]	Shao Q, Huang L, Zhou J, Lu L, Zhang L, Lu X, Jiang S, Gubbins K E, Shen W.Molecular simulation study of temperature effect on ionic hydration in carbon nanotubes[J].Physical Chemistry Chemical Physics, 2008,10(14):1896-1906
[13]	Shao Q, Zhou J, Lu L, Lu X, Zhu Y, Jiang S.Anomalous hydration shell order of Na+ and K+ inside carbon nanotubes[J].Nano Letters, 2009,9(3):989-994
[14]	Zhu Y, Wei M, Shao Q, Lu L, Lu X, Shen W.Molecular dynamics study of pore inner wall modification effect in structure of water molecules confined in single-walled carbon nanotubes[J].The Journal of Physical Chemistry C, 2009,113(3):882-889
[15]	Guo X, Shao Q, Lu L, Zhu Y, Wei M, Lu X.Molecular dynamics simulation study of ionic hydration in negatively charged single-walled carbon nanotubes[J].Journal of Nanoscience and Nanotechnology, 2010,10(11):7620-7624
[16]	Zhu Y, Guo X, Shao Q, Wei M, et al.Molecular simulation study of the effect of inner wall modified groups on ionic hydration confined in carbon nanotube[J].Fluid Phase Equilibria, 2010,297(2):215-220
[17]	Giovambattista N, Debenedetti P G, Rossky P J.Effect of surface polarity on water contact angle and interfacial hydration structure[J].The Journal of Physical Chemistry B, 2007,111(32):9581-9587
[18]	Giovambattista N, Debenedetti P G, Rossky P J.Hydration behavior under confinement by nanoscale surfaces with patterned hydrophobicity and hydrophilicity[J].The Journal of Physical Chemistry C, 2007,111(3):1323-1332
[19]	Giovambattista N, Debenedetti P G, Rossky P J.Enhanced surface hydrophobicity by coupling of surface polarity and topography[J].Proceedings of the National Academy of Sciences, 2009,106(36):15181-15185
[20]	Giovambattista N, Rossky P J, Debenedetti P G.Effect of temperature on the structure and phase behavior of water confined by hydrophobic, hydrophilic, and heterogeneous surfaces[J].The Journal of Physical Chemistry B, 2009,113(42):13723-13734
[21]	Romero-Vargas Castrilloón S, Giovambattista N S, Aksay I A,Debenedetti P G.Effect of surface polarity on the structure and dynamics of water in nanoscale confinement[J].The Journal of Physical Chemistry B, 2009,113(5):1438-1446
[22]	Garde S, Patel A J.Unraveling the hydrophobic effect, one molecule at a time[J].Proceedings of the National Academy of Sciences, 2011,108(40):16491-16492
[23]	Patel A J, Varilly P, Jamadagni S N, Acharya H, Garde S, Chandler D.Extended surfaces modulate hydrophobic interactions of neighboring solutes[J].Proceedings of the National Academy of Sciences, 2011,108(43):17678-17683
[24]	Wei M J, Zhou J, Lu X, Zhu Y, Liu W, Lu L, Zhang L. Diffusion of water molecules confined in slits of rutile TiO2(110)and graphite(0001)[J].Fluid Phase Equilibria, 2011,302(1/2):316-320
[25]	Striolo A.From interfacial water to macroscopic observables:a review[J].Adsorption Science & Technology, 2011,29(3):211-258
[26]	Ho T A, Papavassiliou D V, Lee L L, Striolo A.Liquid water can slip on a hydrophilic surface[J].Proceedings of the National Academy of Sciences, 2011,108(39):16170-16175
[27]	Akhavan O, Ghaderi E.Photocatalytic reduction of graphene oxide nanosheets on TiO2 thin film for photoinactivation of bacteria in solar light irradiation[J].The Journal of Physical Chemistry C, 2009,113(47):20214-20220
[28]	Ng Y H, Lightcap I V, Goodwin K, Matsumura M, Kamat P V.To what extent do graphene scaffolds improve the photovoltaic and photocatalytic response of TiO2 nanostructured films?[J].The Journal of Physical Chemistry Letters, 2010,1(15):2222-2227
[29]	Xu Y J, Zhuang Y, Fu X.New insight for enhanced photocatalytic activity of TiO2 by doping carbon nanotubes:a case study on degradation of benzene and methyl orange[J].The Journal of Physical Chemistry C, 2010,114(6):2669-2676
[30]	Zhang Y, Tang Z R, Fu X, Xu Y J.TiO2—graphene nanocomposites for gas-phase photocatalytic degradation of volatile aromatic pollutant:is TiO2—graphene truly Different from other TiO2—carbon composite materials?[J].ACS Nano, 2010,4(12):7303-7314
[31]	Wang D, Choi D, Li J, Yang Z, Nie Z, Kou R, Hu D, Wang C, Saraf L V, Zhang J, Aksay I A, Liu J.Self-assembled TiO2-graphene hybrid nanostructures for enhanced Li-ion insertion[J].ACS Nano, 2009,3(4):907-914
[32]	Williams G, Seger B, Kamat P V.TiO2-graphene nanocomposites.UV-assisted photocatalytic reduction of graphene oxide[J].ACS Nano, 2008,2(7):1487-1491
[33]	Li Q, Yang H, Qiu F, Zhang X.Promotional effects of carbon nanotubes on V2O5/TiO2 for NOx removal[J].Journal of Hazardous Materials, 2011,192(2):915-921
[34]	Berendsen H J C, Grigera J R, Straatsma T P.The missing term in effective pair potentials[J].The Journal of Physical Chemistry, 1987,91(24):6269-6271
[35]	Matsui M, Akaogi M.Molecular dynamics simulation of the structural and physical properties of the four polymorphs of TiO2[J].Molecular Simulation, 1991,6:239-244
[36]	Naicker P K, Cummings P T, Zhang H Z, Banfield J F. Characterization of titanium dioxide nanoparticles using molecular dynamics simulations[J].The Journal of Physical Chemistry B, 2005,109:15243-15249
[37]	Bandura A V, Kubicki J D.Derivation of force field parameters for TiO2-H2O systems from ab initio calculations[J].The Journal of Physical Chemistry B, 2003,107:11072-11081
[38]	Predota M, Bandura A V, Cummings P T, Kubicki J D, Wesolowski D J, Chialvo A A, Machesky M L.Electric double layer at the rutile(110)surface(Ⅰ):Structure of surfaces and interfacial water from molecular dynamics by use of ab initio potentials[J].The Journal of Physical Chemistry B, 2004,108(32):12049-12060
[39]	Jorgensen W L, Maxwell D S, Tirado-Rives J.Development and testing of the OPLS all-atom force field on conformational energetics and properties of organic liquids[J].Journal of the American Chemical Society, 1996,118(45):11225-11236
[40]	Skelton A A, Walsh T R.Interaction of liquid water with the rutile TiO2(110)surface[J].Molecular Simulation, 2007,33(4/5):379-389
[41]	Smith W, Forester D R.CCP5 - a collaborative computational project for the computer-simulation of condensed phases[J].Journal of Molecular Graphics, 1987,5:71-74
[42]	Smith W, Forester T R.DL_POLY_2.0:a general-purpose parallel molecular dynamics simulation package[J].Journal of Molecular Graphics, 1996,14(3):136-141
[43]	Berendsen H J C, Postma J P M, Gunsteren W F, Dinola A,Haak J R.Molecular dynamics with coupling to an external bath[J].The Journal of Chemical Physics, 1984,81(8):3684-3690
[44]	Darden T, York D,Pedersen L.Particle mesh Ewald:an N·log(N)method for Ewald sums in large systems[J].The Journal of Chemical Physics, 1993,98(12):10089-10092
[45]	Murata K, Mitsuoka K, Hirai T, Walz T, Agre P, Heymann J B, Engel A,Fujiyoshi Y.Structural determinants of water permeation through aquaporin-1[J].Nature, 2000,407(6804):599-605
[46]	Hummer G, Rasaiah J C,Noworyta J P.Water conduction through the hydrophobic channel of a carbon nanotube[J].Nature, 2001,414(6860):188-190
[47]	Agre P.Aquaporin water channels[J].Bioscience Reports, 2004,24(3):127-163
[48]	Joseph S,Aluru N R.Why are carbon nanotubes fast transporters of water?[J].Nano Letters, 2008,8(2):452-458