Microwave-assisted solvothermal: An efficient and new method to obtain hydrophobic wood surfaces
Keywords:
Nanoparticles, Pinus elliotti, wettability, wood modification, wood technologyAbstract
The objective of this work was to form a hydrophobic surface in a highly porous wood by coating and incorporating TiO2 micro/nano structures through the microwave-assisted solvotermal method, without need any pre- or post-modification of the wood substrate, using low temperatures and short times. The behavior and morphology of the TiO2-treated surfaces was characterized using scanning electron microscopy (SEM), while the elemental composition was determined via energy-dispersive X-ray spectroscopy and X-ray diffraction analysis. The results indicated that the crystallization of the TiO2 anatase phase was efficient and fully coated the wood surface during the solvothermal process. The treated wood contained TiO2 particles with an average diameter of 200 nm that also allowed to coat an abundant fraction of tracheids cell walls. When investigated through X-ray spectroscopy-mapping, the element titanium appeared abundantly throughout the wood. After TiO2 growth in wood through the microwave-assisted solvotermal method, a roughness at the micro/nano scales structures was created on the wood surface, originating an increase in the contact angle up to 137°, which characterizes the appearance of a hydrophobic surface. The TiO2-treated wood demonstrated 85% of water absorption after 400 hours of immersion, while untreated wood reached 160%, suggesting that the microwave-assisted solvotermal process promotes a delay in the progression of water absorption. This feature can improve the dimensional stability of wood, contributing to the increase of its durability and applications.
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References
DIEBOLD, U. 2003. The surface science of titanium dioxide. Surface Science Reports 48 (5): 53-229.
EL OUDIANI, A.; CHAABOUNI, Y.; MSAHLI, S.; SAKLI, F. 2011. Crystal transition from cellulose I to cellulose II in NaOH treated Agave americana L. fibre. Carbohydrate Polymers 86 (3): 1221-1229.
EVANS, P. D.; WALLIS, A. F. A.; OWEN, N. L. 2000. Weathering of chemically modified wood surfaces. Wood Science and Technology 34 (2): 151-165.
GAO, L.; ZHAN, X.; LU, Y.; LI, J.; SUN, Q. 2015. pH-dependent structure and wettability of TiO2-based wood surface. Materials Letters 142: 217-220.
HUANG, Z.; MANESS, P. C.; BLAKE, D. M.; WOLFRUM, E. J.; SMOLINSKI, S. L.; JACOBY, W. A. 2000. Bactericidal mode of titanium dioxide photocatalysis. Journal of Photochemistry and Photobiology A: Chemistry 130 (2): 163-170.
JIA, S.; LIU, M.; WU, Y.; LUO, S.; QING, Y.; CHEN, H. 2016. Facile and scalable preparation of highly wear-resistance superhydrophobic surface on wood substrates using silica nanoparticles modified by VTES. Applied Surface Science 386: 115-124.
LEE, S.; CHO, I. S.; NOH, J. H.; HONG, K. S.; HAN, G. S.; JUNG, H. S.; SHIN, H. 2010. Correlation of anatase particle size with photocatalytic properties. Physica Status Solidi (a) 207 (10): 2288-2291.
LESAR, B.; HUMAR, M. 2011. Use of wax emulsions for improvement of wood durability and sorption properties. European Journal of Wood and Wood Products 69 (2): 231-238.
LIU, M.; QING, Y.; WU, Y.; LIANG, J.; LUO, S. 2015. Facile fabrication of superhydrophobic surfaces on wood substrates via a one-step hydrothermal process. Applied Surface Science 330: 332-338.
LU, X.; HU, Y. 2016. Layer-by-layer deposition of TiO2 nanoparticles in the wood surface and its superhydrophobic performance. BioResources 11 (2): 4605-4620.
LU, Y.; FENG, M.; ZHAN, H. 2014. Preparation of SiO2–wood composites by an ultrasonic-assisted sol–gel technique. Cellulose 21 (6): 4393-4403.
MISSIO, A. L.; DE CADEMARTORI, P. H. G.; MATTOS, B. D.; SANTINI, E. J.; HASELEIN, C. R.; GATTO, D. A. 2016. Physical and Mechanical Properties of Fast-Growing Wood Subjected to Freeze-Heat Treatments. BioResources 11 (4): 10378-10390.
MOURA, K. F.; MAUL, J.; ALBUQUERQUE, A. R.; CASALI, G. P.; LONGO, E.; KEYSON, D.; SANTOS, I. M. G. 2014. TiO2 synthesized by microwave assisted solvothermal method: Experimental and theoretical evaluation. Journal of Solid State Chemistry 210 (1): 171-177.
MOURÃO, H. A. J. L.; MENDONÇA, V. D.; MALAGUTTI, A. R.; RIBEIRO, C. 2009. Nanoestruturas em fotocatálise: uma revisão sobre estratégias de síntese de fotocatalisadores em escala nanométrica. Química Nova 32 (8): 2181-2190.
PERRONE, O. M. 2015. Avaliação térmica e estrutural do bagaço de cana de açúcar pré tratado com ozônio, ultrassom e micro-ondas para produção de etanol celulósico por hidrólise enzimática. http://repositorio.unesp.br/handle/11449/127894, (accessed 02.12.2016).
RASSAM, G.; ABDI, Y.; ABDI, A. 2012. Deposition of TiO2 nano-particles on wood surfaces for UV and moisture protection. Journal of Experimental Nanoscience 7 (4): 468-476.
SEDIGHI-MOGHADDAM, M. 2015. Wettability of modified wood (Doctoral Dissertation, KTH Royal Institute of Technology).
SIEGLOCH, A. M.; MARCHIORI, J. N. C. 2015. Anatomia da madeira de treze espécies de coníferas. Revista Ciência da Madeira (Brazilian Journal of Wood Science) 6 (3). 149-165.
SUN, Q.; LU, Y.; ZHANG, H.; ZHAO, H.; YU, H.; XU, J.; LIU, Y. 2012. Hydrothermal fabrication of rutile TiO2 submicrospheres on wood surface: an efficient method to prepare UV-protective wood. Materials Chemistry and Physics 133 (1): 253-258.
SUN, Q.; YU, H.; LIU, Y.; LI, J.; LU, Y.; HUNT, J. F. 2010. Improvement of water resistance and dimensional stability of wood through titanium dioxide coating. Holzforschung 64 (6): 757-761.
WANG, B.; FENG, M.; ZHAN, H. 2014. Improvement of wood properties by impregnation with TiO2 via ultrasonic-assisted sol–gel process. RSC Advances 4 (99): 56355-56360.
WANG, X.; LIU, J.; CHAI, Y. 2012. Thermal, mechanical, and moisture absorption properties of wood-TiO2 composites prepared by a sol-gel process. BioResources 7 (1): 0893-0901.
WANG, X.; TIAN, J.; FEI, C.; LV, L.; WANG, Y.; CAO, G. 2015. Rapid construction of TiO2 aggregates using microwave assisted synthesis and its application for dye-sensitized solar cells. RSC Advances 5 (12): 8622-8629.
WIMMER, R. 2002. Wood anatomical features in tree-rings as indicators of environmental change. Dendrochronologia 20 (1-2): 21-36.
ZANATTA, P.; LAZAROTTO, M.; GONZALEZ DE CADEMARTORI, P. H.; CAVA, S. D. S.; MOREIRA, M. L.; GATTO, D. A. 2017. The effect of titanium dioxide nanoparticles obtained by microwave-assisted hydrothermal method on the color and decay resistance of pinewood. Maderas-Cienc Tecnol 19 (4): 495-506.
ZHANG, X.; SHI, F.; NIU, J.; JIANG, Y.; WANG, Z. 2008. Superhydrophobic surfaces: from structural control to functional application. Journal of Materials Chemistry 18 (6): 621-633.
ZHENG, R.; TSHABALALA, M. A.; LI, Q.; WANG, H. 2015. Construction of hydrophobic wood surfaces by room temperature deposition of rutile (TiO2) nanostructures. Applied Surface Science 328: 453-458.
