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Pressure Induced Structural and Electronic Bandgap Properties
of Anatase and Rutile TiO2
(Struktur dan Tekanan Ciri
Jurang Jalur Elektronik Anatas dan TiO2 Rutil yang dirangsang oleh Tekanan)
Tariq Mahmood1,2*, Chuanbao Cao1, Rashid Ahmed3,
Maqsood Ahmed2, M. A. Saeed3, Abrar Ahmed Zafar2,
Talab Husain2 & M.A. Kamran1
1School of Materials Science and
Engineering, Beijing Institute of Technology, Beijing-100081
P.R. China
2Centre for High Energy Physics, University
of the Punjab, Lahore-54590, Pakistan
3Physics Department, Faculty of Science, Universiti
Teknologi Malaysia, UTM Skudai, 81310 Johor
Malaysia
Diserahkan: 7
Januari 2012 / Diterima: 21 Mei 2012
ABSTRACT
In this study, we present the structural
and electronic bandgap properties of anatase and rutile titanium dioxide by
applying ultrasoft pseudo-potential plane wave approach developed within the
frame of density functional theory (DFT).
We used generalized gradient approximation (GGA)
proposed by Perdew-Burke-Ernzerhof (PBE)
for exchange correlation potential. In our pressure driven investigations,
geometry optimization is carried out for different values of pressure over a
range of 0-100 GPa and subsequently related structural parameters and bandgap
values of anatase and rutile titanium dioxide (TiO2)
have been calculated. In both cases, the lattice constants (a, c) and volume
decreased as the pressure was increased. Similarly, internal parameter for
anatase increased and for rutile TiO2 it decreased under high pressure.
The value of c/a decreased for anatase and increased for rutile TiO2 as a function of pressure. Our band structure analysis showed
different behavior of bandgap between anatase and rutile TiO2.
The conduction band of anatase TiO2 moved
opposite to the conduction band of rutile TiO2 as we increase the pressure.
Additionally we used the Birch-Murnaghan equation of state to obtain the
equilibrium volume (V0),
bulk modulus (B0)
and pressure derivative of bulk modulus (B0’) at zero pressure. The calculated
results are in good agreement with previous experimental as well as theoretical
results.
Keywords: Conduction band; density
function theory; pressure
ABSTRAK
Di dalam
kajian ini, kami membentangkan ciri struktur dan jurang jalur elektronik bagi
anatas dan titanium dioksida rutil dengan menggunakan pendekatan gelombang
satah pseudo-keupayaan ultralembut yang dibangunkan dalam kerangka teori fungsi
ketumpatan (DFT). Kami menggunakan penganggaran ceruk umum (GGA)
yang diusulkan oleh Perdew-Burke-Ernzerhof (PBE)
untuk keupayaan korelasi pertukaran. Kajian tekanan
yang didorong pengoptimuman geometri telah dijalankan untuk nilai tekanan yang
berbeza pada julat 0-100 GPa. Parameter struktur dan
nilai jurang jalur anatas dan titanium dioksida rutil telah dikira. Dalam kedua-dua kes, nilai pemalar kekisi (a, c) dan isi padu
menurun apabila tekanan meningkat. Parameter dalaman
untuk anatas meningkat dan untuk TiO2 rutil menurun pada tekanan
tinggi. Nilai c/a menurun untuk anatas dan meningkat
untuk TiO2 rutil sebagai fungsi tekanan. Analisis
struktur jalur menunjukkan tingkah laku yang berbeza antara jurang jalur anatas
dan TiO2 rutil. Jalur konduksi anatas TiO2 bergerak dengan berlawanan arah terhadap jalur konduksi TiO2, rutil apabila tekanan
meningkat. Persamaan keadaan Birch-Murnaghan telah
digunakan untuk mendapatkan isi padu keseimbangan (V0)
modulus pukal (B0) dan
terbitan tekanan modulus pukal (B0’)
pada tekanan sifar. Keputusan yang diperoleh adalah
selari dengan keputusan uji kaji dan teori yang sebelumnya.
Kata
kunci: Jalur konduksi; tekanan; teori fungsi ketumpatan
RUJUKAN
Arlt,
T., Bermejo, M., Blanco, M.A., Gerward, L., Jiang, J.Z., Staun Olsen, J. &
Recio, J.M. 2000. High-pressure polymorphs of anatase TiO2. Phys. Rev. B 61(21):
14414-14419.
Asahi,
R., Taga, Y., Mannstadt, W. & Freeman, A.J. 2000. Electronic
and optical properties of anatase TiO2. Phys. Rev. B 61(11): 7459-7465.
Asahi,
R., Morikawa, T., Ohwaki, T., Aoki, K. & Taga, Y. 2001. Visible-light
photocatalysis in nitrogen-doped titanium oxides. Science 293:
269-271.
Baizaee, S.M. &
Mousavi, N. 2009. First-principles study of the electronic and optical
properties of rutile TiO2. Phyica
B 404: 2111-2116.
Burdett,
J.K., Hughbanks, T., Miller, G.J., Richardson, J.W. Jr. & Smith, J.V. 1987. Structural-electronic
relationships in inorganic solids: Powder neutron diffraction studies of the
rutile and anatase polymorphs of titanium dioxide at 15 and 295 K. J. Am.
Chem. Soc. 109(12): 3639-3646.
Carp,
O., Huisman, C.L. & Reller, A. 2004. Photoinduced
reactivity of titanium dioxide. Prog. Solid State Chem. 32(1-2):
33-177.
Chen, Q. & Cao, H-H.
2004. Ab initio calculations of electronic structure of anatase TiO2 Chinese Physics B 13(12):
2121.
Cho, E., Han, S., Ahn,
H-S., Lee, K-R., Kim, S.K. & Hwang, C.S. 2006. First-principles study of
point defects in rutile TiO2−x. Phys.
Rev. B 73(19): 193202.
Di
Valentin, C., Pacchioni, G. & Selloni, A. 2004. Origin
of the different photoactivity of n-doped anatase and rutile TiO2. Phys. Rev. B 70(8): 085116.
Di
Valentin, C., Pacchioni, G., Selloni, A., Livraghi, S. & Giamello, E. 2005. Characterization of
paramagnetic species in n-doped TiO2 powders
by EPR spectroscopy and DFT calculations. J. Phys. Chem. B 109:
11414-11419.
Diebold, U. 2003. The surface science of titanium dioxide. Surf. Sci. Rep. 48(5-8):
53-229.
Diwald,
O., Thompshon, T.L., Zubkov, T., Goralski, E.G., Walck, S.D. & Yates, J.T.
Jr. 2004. Photochemical activity of nitrogen-doped rutile TiO2(110) in visible light. J.
Phys. Chem. B 108(19): 6004-6008.
Fische, T.H. &
Almlof, J. 1992. General methods for geometry and wave
function optimization. J. Phys. Chem. 96: 9768-9774.
Fox,
H., Newman, K.E., Schneider, W.F. & Corecelli, S.A. 2010. Bulk
and surface properties of rutile TiO2 from
self-consistent-charge density functional tight binding. J. Chem. Theory Comput. 6: 499-507.
Fujishima, A. &
Honda, K. 1972. Electrochemical photolysis of water at a
semiconductor electrode. Nature 238(5358): 37-38.
Gole,
J.L., Stout, J.D., Burda, C., Lou, Y. & Chen, X. 2004. Highly
efficient formation of visible light tunable TiO2-xNx photocatalysts and their
transformation at the nanoscale. J. Phys. Chem. B 108(4):
1230-1240.
Griffin, G.L. &
Siefering, K.L. 1990. Growth kinetics of CVD TiO2:
Influence of carrier gas. J. Electrochem. Soc. 137(4): 1206-1208.
Irie, H., Watanabe, Y.
& Lindquist, S-E. 2003. Nitrogen-concentration dependence on photocatalytic
activity of TiO2-xNx powders. J. Phys. Chem. B 107(23): 5483-5486.
Islam, M.M., Bredow, T.
& Gerson, A. 2007. Electronic properties of
oxygen-deficient and aluminum-doped rutile TiO2 from first principles. Phys. Rev. B 76(4): 045217.
Iuga,
M., Steinle-Neumann, G. & Meinhardt, J. 2007. Ab-initio simulation of elastic constants for some ceramic materials. Eur.
Phys. J. B 58: 127-133.
Janisch,
R., Gopal, P. & Spaldin, N.A. 2005. Transition metal-doped TiO2 and ZnO-present status of the
field. J. Phys.: Condens. Matter 17(27): R657.
Khan,
S.U.M., Al-Shahry, M. & Ingler, W.B. Jr. 2002. Efficient
photochemical water splitting by a chemically modified n-TiO2. Science 297(5590):
2243-2245.
Labat,
F., Baranek, P., Domain, C., Minot, C. & Adamo, C. 2007. Density functional
theory analysis of the structural and electronic properties of TiO2 rutile and anatase polytypes:
Performances of different exchange-correlation functional. J. Chem. Phys. 126(15):
154703.
Lazzeri,
M., Vittadini, A. & Selloni, A. 2001. Structure and
energetics of stoichiometric TiO2 anatase
surfaces. Phys. Rev. B 63(15): 155409.
Lin,
Zh., Orlov, A., Lambert, R.M. & Payne, M.C. 2005. New
insights into the origin of visible light photocatalytic activity of
nitrogen-doped and oxygen-deficient anatase TiO2. J. Phys. Chem. B 109(44):
20948-20952.
Lindgren,
T., Mwabora, J.M., Avendano, E., Jansson, J., Hoel, A., Granqvist, C-G. & Lindquist, S-E.
2003. Photoelectrochemical and optical properties of nitrogen doped titanium
dioxide films prepared by reactive DC magnetron sputtering. J. Phys. Chem. B 107(24): 5709-5716.
Liu,
Y., Ni, L., Ren, Z., Xu, G., Song, C. & Han, G. 2009. Negative pressure
induced ferroelectric phase transition in rutile TiO2. J. Phys.: Condens. Matter 21(27): 275901.
Ma,
X.G., Liang, P., Miao, L., Bei, S.W., Zhang, C.K., Xu, L. & Jiang, J.J.
2009. Pressure-induced phase transition and elastic properties of TiO2 polymorphs. Phys. Status Solidi B 246(9): 2132-2139.
Mattioli,
G., Filippone, F., Alippi, P. & Bonapasta, A.A. 2008. Ab initio study
of the electronic states induced by oxygen vacancies in rutile and anatase TiO2. Phys. Rev. B 78(24):
241201.
Monkhorst, H.J. &
Pack, J.D. 1976. Special points for Brillouin-zone
integrations. Phys. Rev. B 13: 5188-5192.
Murnaghan, F.D. 1944. The compressibility of media under extreme pressures. Proc. Natl. Acad. Sci. USA 30(9): 244-247.
Nakamura,
R., Tanaka, T. & Nakato, Y. 2004. Mechanism for visible light
responses in anodic photocurrents at n-doped TiO2 film electrodes. J. Phys. Chem. B 108(30):
10617-10620.
Pascual, J., Camassel, J. & Mathieu,
H. 1978. Fine structure in the intrinsic absorption edge of
TiO2. Phys. Rev. B 18(10):
5606-5614.
Perdew, J.P., Burke, K.
& Ernzerhof, M. 1996. Generalized gradient approximation made simple. Phys. Rev. Lett. 77:
3865-3868.
Persson, C. & da Silva, A.F. 2005.
Strong polaronic effects on rutile TiO2 electronic band edges. Appl. Phys.
Letts. 86(23): 231912.
Sakthivel, S. & Kisch, H. 2003. Photocatalytic and photoelectrochemical properties of
nitrogen-doped titanium dioxide. ChemPhysChem 4(5): 487-490.
Segall, M.D., Lindan,
P., Probet, M.J., Pickard, C.J., Hasnip, P.J., Clark, S.J. & Payne, M.C.
2002. First-principles simulation: Ideas, illustrations and the CASTEP code. J.
Phys. Condens. Matter 14: 2717-2744.
Shi, H., Luo, W., Johansson, B. &
Ahujia, R. 2009. Electronic and elastic properties of CaF2 under high pressure from ab initio calculations. J.
Phys. Condens. Matter 21(41): 415501.
Shirley, R., Kraft, M.
& Inderwildi, O.R. 2010. Electronic and optical properties of aluminium-doped anatase
and rutile TiO2 from ab initio calculations. Phys. Rev. B 81:
075111.
Swamy, V. & Muddle, B.C. 2007.
Ultrastiff cubic TiO2 identified via first-principles calculations. Phys.
Rev. Lett. 98(3): 035502.
Tang, H., Berger, H.,
Schmid, P.E., Levy, F. & Burri, G. 1993. Photoluminescence in
TiO2 anatase single crystals. Solid State Commun. 87(9): 847-850.
Tariq Mahmood, Chuanbao Cao, Waheed S.
Khan, Zahid Usman, Faheem K. Butt, Sajad Hussain. 2012. Electronic, elastic,
optical properties of rutile TiO2 under pressure: A DFT study. Physica B:
Condensed Matter 207: 958-965.
Thilagam, A., Simpson,
D.J. & Gerson, A.R. 2011. A first-principles study of the dielectric properties of TiO2
polymorphs. J. Phys. Condens. Matter 23(2): 025901.
Varghese, O.K. & Grimes, C.A. 2003.
Metal oxide nanoarchitectures for environmental sensing. J. Nanosci.
Nanotech. 3(4): 277-293.
Wu, J.M. & Chen, C.J. 1990. Effect of
powder characteristics on microstructures and dielectric properties of (Ba,Nb)-doped titania ceramics. J. Am. Ceram. Soc. 73(2):
420-424.
Yahya Al-Khatabeh, Kanani K.M. Lee and
Boris Kiefer. 2009. High-pressure behavior of TiO2 as determined by experiment
and theory. Phys. Rev. B 79(13): 134114.
Yin, W-J., Chen,
S., Yang, J-H., Gong, X-G., Yan, Y. & Wei, S-H. 2010. Effective bandgap
narrowing of anatase TiO2 by strain along a soft crystal direction. Appl.
Phys. Lett. 96(22): 221901.
Zhao, W., Ma, W., Chen,
Ch., Zhao, J. & Shuai, Zh. 2004. Efficient degradation of toxic organic
pollutants with Ni2O3/TiO2-xBx under visible irradiation. J.
Am. Chem. Soc. 126(15): 4782-4783.
Zhou, X-F., Dong, X., Qian, G-R., Zhang, L., Tian, Y. & Wang, H-T. 2010. Unusual
compression behavior of TiO2 polymorphs from first principles. Phys. Rev. B 82(6):
060102(R).
*Pengarang untuk surat-menyurat; email: tariq_mahmood78@hotmail.com
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