Titania-lanthanum phosphate photoactive and hydrophobic new generation catalyst

Journal Article · Fri Jul 15 04:00:00 UTC 2011 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2011.05.020· OSTI ID:21580164

Jyothi, Chembolli K; Jaimy, Kanakkanmavudi B ^[1]; Ghosh, Swapankumar ^[1]; Sankar, Sasidharan; Smitha, V S ^[1]; Warrier, K G.K., ^[1]

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1. National Institute for Interdisciplinary Science and Technology (NIIST), CSIR, Trivandrum 695019 (India)

Titania-lanthanum phosphate nanocomposites with multifunctional properties have been synthesized by aqueous sol-gel method. The precursor sols with varying TiO{sub 2}:LaPO{sub 4} ratios were applied as thin coating on glass substrates in order to be transparent, hydrophobic, photocatalytically active coatings. The phase compositions of the composite powders were identified by powder X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HR-TEM). The anatase phase of TiO{sub 2} in TiO{sub 2}-LaPO{sub 4} composite precursors was found to be stable even on annealing at 800 deg. C. The glass substrates, coated with TL1 (TiO{sub 2}-LaPO{sub 4} composition with 1 mol% LaPO{sub 4}) and TL50 (composite precursor containing TiO{sub 2} and LaPO{sub 4} with molar ratio 1:1) sols and annealed at 400 deg. C, produced contact angles of 74 deg. and 92 deg., respectively, though it is only 62 deg. for pure TiO{sub 2} coating. The glass substrates, coated with TL50 sol, produced surfaces with relatively high roughness and uneven morphology. The TL1 material, annealed at 800 deg. C, has shown the highest UV photoactivity with an apparent rate constant, k{sub app}=24x10{sup -3} min{sup -1}, which is over five times higher than that observed with standard Hombikat UV 100 (k{sub app}=4x10{sup -3} min{sup -1}). The photoactivity combined with a moderate contact angle (85.3 deg.) shows that this material has a promise as an efficient self-cleaning precursor. - Graphical abstract: Multifunctional TiO{sub 2}-LaPO{sub 4} composite stabilizes anatase phase with enhanced photocatalytic activity, and moderately higher hydrophobicity is a promising material for self-cleaning application. Highlights: > Titania-lanthanum phosphate nanocomposites were synthesized by aqueous sol-gel method. > Transparent, hydrophobic, photoactive coatings were developed on glass substrates. > The glass substrates, coated with TL1 annealed at 400 deg. C, produced a contact angle of 74 deg. > The TL1 material at 800 deg. C has shown the highest UV photoactivity (k{sub app}=24x10{sup -3} min{sup -1}). > Photoactivity and moderate contact angle show that this is an efficient self-cleaning precursor.

• OSTI ID: 21580164
• Journal Information: Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Journal Issue: 7 Vol. 184; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
ANNEALING
CATALYSIS
CHALCOGENIDES
COHERENT SCATTERING
COLLOIDS
COMPOSITE MATERIALS
DIFFRACTION
DISPERSIONS
ELECTRON MICROSCOPY
GLASS
HEAT TREATMENTS
KINETICS
LANTHANUM COMPOUNDS
LANTHANUM PHOSPHATES
MATERIALS
MICROSCOPY
MORPHOLOGY
NANOSTRUCTURES
OXIDES
OXYGEN COMPOUNDS
PHOSPHATES
PHOSPHORUS COMPOUNDS
PHOTOCATALYSIS
PRECURSOR
RARE EARTH COMPOUNDS
REACTION KINETICS
SCATTERING
SOL-GEL PROCESS
SOLS
SUBSTRATES
TITANIUM COMPOUNDS
TITANIUM OXIDES
TRANSITION ELEMENT COMPOUNDS
TRANSMISSION ELECTRON MICROSCOPY
X-RAY DIFFRACTION