Study on the formation process of Al2O3-TiO2 composite powders

Fine particles of anatase were suspended in solutions of ammonium alum with Al₂O₃/TiO₂ molar ratios from 0.1:1 to 7:1. By spray drying the suspensions and calcining the spray-dried powders, Al₂O₃-TiO₂ composite particles were obtained. The results show that after the spray drying, coatings of ammomium alum are formed on the surface of the anatase particles, leading to composite precursor powders (CCPs) with larger particle sizes. Upon calcining the CCPs, ammomium alum pyrolyzes to amorphous Al₂O₃ and anatase transforms into rutile. Both are mainly responsible for the observed particle size reductions as well as the densification of each composite particle. The in-situ formed α-Al₂O₃ and rutile may have higher reactivities, forming aluminum titanate at 1150 °C, about 130 °C lower than the theoretical temperature for the formation of Al₂TiO₅ by solid reaction. The reaction between α-Al₂O₃ and rutile starts from the interface between the anatase and the alum coating and mainly takes place in the single particles formed by spray drying. The molar ratio of Al₂O₃ to TiO₂ influences the final crystalline phases in the composite powders, but not stoichiometrically.     

Influence of surface modification on the dispersion of nanoscale α‐Al2O3 particles in a thermoplastic polyurethane matrix

In this study, two types of nanoscale α‐Al₂O₃ particles were used for preparation of α‐Al₂O₃/thermoplastic polyurethane (TPU) composites. These α‐Al₂O₃ particles were either coated or uncoated with stearic acid. For the uncoated α‐Al₂O₃/TPU composite, the results of field‐emission scanning electron microscopy (FE‐SEM) and energy dispersive X‐ray spectrometry indicate that uncoated α‐Al₂O₃ particles are significantly aggregated together. This aggregation is due to the poor compatibility between the inorganic filler (α‐Al₂O₃) and the organic matrix (TPU). The size of clusters is in the range from 5 to 20 μm. For the coated α‐Al₂O₃/TPU composite, FE‐SEM results indicate that most coated α‐Al₂O₃ particles are well dispersed in the TPU matrix. This phenomenon results from the effect of surface modifier (i.e., stearic acid) on α‐Al₂O₃ particles. Stearic acid can act as a compatibilizer to bridge the boundary between the TPU matrix and the α‐Al₂O₃ particle. Stearic acid is not only a suitable surface modifier for the nanoscale α‐Al₂O₃ particle, but also a good dispersant for the dispersion of nanoscale α‐Al₂O₃ particles in the TPU matrix. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Preparation and characterization of Polyimide/Al2O3 nanocomposite film with good corona resistance

Polyimide/Al2O3 (PI/Al2O3) nanocomposite films based on pyromellitic dianhydride and 4,4′‐oxydianiline were fabricated by adding different proportions of nano‐Al₂O₃ inorganic particles via in situ polymerization. Microstructural analysis by scanning electron microscope (SEM) showed that the inorganic particles were homogenously dispersed in the PI matrix when mixed with appropriate amount of nano‐Al₂O₃. Fourier transform infrared spectroscopy and X‐ray diffraction analysis were also used to investigate the effect of nano‐Al₂O₃ on the polymerization process. The obtained composite films and pure film were characterized by thermogravimetry analysis, and the experimental results indicated that when comparing with pure film, the nanocomposite films displayed a better thermal stability than the pure one. Moreover, results also showed that the thermal stability of composite films steadily improved with increased content of nano‐Al₂O₃ particle. The electrical property test demonstrated that the composite films performed improving electrical breakdown strength and corona resistance. The microstructure changes of pure film and PI/Al₂O₃ nanocomposite films during corona aging have been analyzed by SEM. POLYM. COMPOS., 37:763–770, 2016. © 2014 Society of Plastics Engineers     

On the Mechanism of Low Temperature Oxidation for Aluminum Particles down to the Nano‐Scale

The oxidation of Al‐particles down to nano‐scale was investigated by TG, SEM and in‐situ X‐ray diffraction. Al particles are usually coated by a 2–4 nm layer of Al₂O₃ which can be derived from the degree of weight increase on complete oxidation by TG‐curves. The low temperature oxidation of Al particles occurs at least in two steps. The first step builds a layer of 6 to 10 nm thickness composed of crystallites of the same size independent on the initial particle size. This reaction is dominated by chemical kinetics and converts a substantial fraction of the particle if the particle sizes decrease below 1 μm, an effect carefully to be taken into account for nano‐particles because of safety reasons. The second step combines diffusion and chemical reaction and proceeds therefore slowly, the slower the bigger the particles are. The kinetic parameters of these two steps can be obtained by a model taking into account both reaction steps, chemical kinetics and diffusion for spherical particles when fitting it to TG‐curves. X‐ray diffraction shows that particles smaller than 1 μm build γ‐ and θ‐Al₂O₃ in the first step with nano‐crystalline structures which are then transformed to α‐Al₂O₃.     

Structure and properties of composite films prepared from cellulose and nanocrystalline titanium dioxide particles

Composite films were successfully prepared from cellulose and two kinds of nanocrystalline TiO₂ particles in a NaOH/urea aqueous solution (7.5 : 11 in wt %) by coagulation with H₂SO₄ solution. The structure, morphology, and properties of the films were characterized by transmission electron microscopy, scanning electron microscopy, X‐ray diffraction, TGA, tensile testing, UV–vis spectroscopy, and antibacterial test. The results indicated that TiO₂ particles in a cellulose matrix maintained the original nanocrystalline structure and properties. TiO₂(I) (anatase) and TiO₂(II) (the mixture of anatase and rutile) particles exhibited a certain miscibility with cellulose. The tensile strength of two kinds of composite films was higher than 70 and 75 MPa, when the content of TiO₂(I) and TiO₂(II) was 4 and 11 wt %, respectively. The cellulose composite films containing nanocrystalline TiO₂ particles displayed distinct antibacterial abilities and excellent UV absorption. This work provides a potential way for preparing functional composite materials from cellulose and inorganic nanoparticles in a NaOH/urea aqueous solution, without a destruction of the structure and properties of the particles. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3600–3608, 2006     

Tribological behavior of micrometer‐ and nanometer‐Al2O3‐particle‐filled poly(phthalazine ether sulfone ketone) copolymer composites used as frictional materials

Micrometer‐ and nanometer‐Al₂O₃‐particle‐filled poly(phthalazine ether sulfone ketone) (PPESK) composites with filler volume fractions ranging from 1 to 12.5 vol % were prepared by hot compression molding. We evaluated the tribological behaviors of the PPESK composites with the block‐on‐ring test rig by sliding PPESK‐based composite blocks against a mild carbon steel ring under dry‐friction conditions. The effects of different temperatures on the wear rate of the PPESK composites were also investigated with a ball‐on‐disc test rig. The wear debris and the worn surfaces of the PPESK composites were investigated with scanning electron microscopy, and the structures of the PPESK composites were analyzed with IR spectra. The lowest wear rate, 7.31 × 10^?6 mm³ N^?1 m^?1, was obtained for the composite filled with 1 vol %‐nanometer Al₂O₃ particles. The composite with nanometer particles exhibited a higher friction coefficient (0.58–0.64) than unfilled PPESK (0.55). The wear rate of 1 vol %‐nanometer‐Al₂O₃‐particle‐filled PPESK was stable and was lower than that of unfilled PPESK from the ambient temperature to 270°C. We anticipate that 1 vol %‐nanometer‐Al₂O₃‐particle‐filled PPESK can be used as a good frictional material. We also found that micrometer‐Al₂O₃‐particle‐filled PPESK had a lower friction coefficient at a filler volume fraction below 5%. The filling of micrometer Al₂O₃ particles greatly increased the wear resistance of PPESK under filler volume fractions from 1 to 12.5%. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 95: 993–1001, 2005     

Effect of mixed size particles reinforcing on the thermal and dynamic mechanical properties of Al2O3/PPS composites

Thermal and dynamic mechanical properties of polyphenylene sulfide (PPS) composites that were reinforced with different sized alumina (Al₂O₃) particles were studied. These composites were manufactured with two different sizes of Al₂O₃ particles 1 and 63 µm, using microcompounding and injection molding. Monosized Al₂O₃ particles reinforced up to 25 wt% loading content and mixed size Al₂O₃ particles reinforced at 15 wt% loading content as following particle weight proportions: 75% × 63 μm + 25% × 1 μm, 50% × 63 μm + 50% × 1 μm, 25% × 63 μm + 75% × 1 μm. Particle distribution investigations were performed by microcomputerized tomography (micro‐CT). Thermal properties were analyzed by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) methods and also dynamic mechanical properties were investigated by dynamic mechanical thermal analysis (DMTA) method. The results showed that mixed size Al₂O₃ particle reinforced composites showed a great enhancement in dynamic mechanical properties without significant change in thermal properties. It was concluded that mixed size particles showed a great synergy to give better results compared with monosized particle reinforced composites. POLYM. COMPOS., 37:3219–3227, 2016. © 2015 Society of Plastics Engineers     

Bi2O3 nanoparticles incorporated porous TiO2 films as an effective p‐n junction with enhanced photocatalytic activity

Porous TiO₂ films decorated with Bi₂O₃ nanoparticles are fabricated via alkali‐hydrothermal of titanium (Ti) plate by varying the reaction time. The amorphous TiO₂ is transformed into anatase after annealing the films at 500°C in air. The p‐type Bi₂O₃ nanoparticles are successfully assembled on the surface of porous n‐type TiO₂ films through the ultrasonic‐assisted successive ionic layer adsorption and reaction (SILAR) technique to form Bi₂O₃/TiO₂ nanostructure by the two cycles. The obtained Bi₂O₃/TiO₂ films are consisted of a well‐ordered and uniform porous structure with an average pore diameter of about 100‐200 nm containing homogeneously dispersed Bi₂O₃ nanoparticles of ~5 nm diameter. Moreover, the resultant composites present excellent photocatalytic performance toward methyl blue (MB) degradation under UV and visible light irradiation, which could be mainly ascribed to the enhanced light adsorption capacity of unique composite structure and the formation of p‐n heterojunctions in the porous Bi₂O₃/TiO₂ films. This research is helpful to design and construct the highly efficient heterogeneous semiconductor photocatalysts.     

Photocatalytic TiO2 films and membranes for the development of efficient wastewater treatment and reuse systems

In order to develop efficient photocatalytic TiO₂ films and membranes for application in water and wastewater treatment and reuse systems, there is a great need to tailor-design the structural properties of TiO₂ material and enhance its photocatalytic activity. Through a simple sol–gel route, employing self-assembled surfactant molecules as pore directing agents along with acetic acid-based sol–gel route, we have fabricated nanostructured crystalline TiO₂ thin films and TiO₂/Al₂O₃ composite membranes with simultaneous photocatalytic, disinfection, separation, and anti-biofouling properties. The highly porous TiO₂ material exhibited high specific surface area and porosity, narrow pore size distribution, homogeneity without cracks and pinholes, active anatase crystal phase, and small crystallite size. These TiO₂ materials were highly efficient in the decomposition of methylene blue dye and creatinine, destruction of biological toxins (microcystin-LR), and inactivation of pathogenic microorganisms (Escherichia coli). Moreover, the photocatalytic TiO₂ membranes exhibited not only high water permeability and sharp polyethylene glycol retention but also less adsorption fouling tendency. Here, we report results on the synthesis, characterization, and environmental application and implication of photocatalytic TiO₂ films and membranes.     

Hybrid polyaniline–TiO2 nanocomposite Langmuir–Blodgett thin films: Self‐assembly and their characterization

Polyaniline (PANi)–titanium dioxide (TiO₂) nanocomposite materials were prepared by chemical polymerization of aniline doped with TiO₂ nanoparticles. Surface pressure–area (π‐A) isotherms of these nanocomposites show phase transformations in the monolayer during compression process. Multiple isotherms indicate that the monolayer of the nanocomposite material can retain its configuration during compression‐expansion cycles. Langmuir–Blodgett thin films of PANi–TiO₂ nanocomposite were deposited on the quartz and indium tin oxide coated conducting glass substrates. Fourier transfer infrared spectroscopy and UV–visible spectroscopy study indicates the presence of TiO₂ in PANi, whereas X‐ray Diffraction study confirmed the anatase phase of TiO₂ and particle size (～nm) of PANi–TiO₂. The morphology of Langmuir–Blodgett films of these nanocomposites was also characterized by atomic force microscopy. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41386.     

Preparation of titanium dioxide/poly(methyl methacrylate‐co‐n‐butyl acrylate‐co‐methacrylic acid) hybrid composite particles via emulsion polymerization

Titanium dioxide core and polymer shell composite poly(methyl methacrylate‐co‐n‐butyl acrylate‐co‐methacrylic acid) [P(MMA‐BA‐MAA)] particles were prepared by emulsion copolymerization. The stability of dispersions of TiO₂ particles in aqueous solution was investigated. The addition of an ionic surfactant, sodium lauryl sulfate, which can be absorbed strongly at the TiO₂/aqueous interface, increases the stability of the TiO₂ dispersion effectively by increasing the absolute value of the ζ potential of the TiO₂ particles. The adsorption of the nonionic surfactant, Triton X‐100, on the surface of TiO₂ particles is less than that of the ionic surfactant. Fourier transform IR spectroscopy was used to measure the content of MAA composite particles. Dynamic light scattering characterized the composite particle size and size distribution. The field‐emission scanning electron microscopy results for the composite particles showed a regular spherical shape, and no bare TiO₂ was detected on the entire surface of the samples. The composite particles that were produced showed good spectral reflectance compared to bare TiO₂. Thermogravimetric analysis results indicated the encapsulated TiO₂ and estimated density of composite particles. There was up to 78.9% encapsulated TiO₂ and the density ranged from 1.76 to 1.94 g/cm³. The estimated density of the composite particles is suitable at 1.73 g/cm³, which is due to density matching with the suspending fluid. The sedimentation experiment indicates that reducing the density mismatch between the composite particles and suspending fluid may enhance the stability. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 72–79, 2005     

Preparation and characteristics of polyimide–TiO2 nanocomposite film

A sol–gel approach has been developed to prepare polyimide–TiO₂ hybrid films from soluble polyimides and a modified titanium precursor. The rate of the hydrolysis reaction of titanium alkoxide can be controlled by using acetic acid as a modifier. FTIR and XPS indicated that TiO₂ particles were well distributed in polyimide matrixes with particle size small per than 60 nm. Polyimide hybrid films having the TiO₂ component ≤10% exhibited high thermal stability, high optical transparency and good mechanical properties and possessed higher dielectric constants than correspondingly polyimides. © 2000 Society of Chemical Industry     

Ethanol‐Water‐Derived Sucrose‐Coated‐Al2O3 for Submicrometer AlON Powder Synthesis

Fluffy and homogenous sucrose‐coated‐γ‐Al₂O₃ structured precursor was prepared by drying ethanol‐water sucrose/Al₂O₃ suspension, in which the ethanol content of 85 vol% was optimized. Using the C/Al₂O₃ mixture pyrolyzed from such precursor with 23.2 wt% sucrose, single‐phase AlON powder was synthesized by two‐step carbothermal reduction and nitridation method at 1550°C for 2 h and 1700°C for another 1.5 h. The particle size of the AlON powder was around 0.6–1.0 μm. Compared with those synthesized by the traditional approaches with mechanical C/Al₂O₃, Al/Al₂O₃, or AlN/Al₂O₃ mixtures, the synthesis temperature was reduced about 50°C, and the AlON powder was fine and exhibited good dispersity. Such superiority of this method was attributed to that the pyrolyzed carbon film on Al₂O₃ particle greatly restrained Al₂O₃ coalescence during the thermal treatment.     

A water‐dispersible conducting nanocomposite from suspension polymerisation of thiophene in presence of N‐vinylcarbazole

The polymerisation of a mixture of thiophene and N‐vinylcarbazole was achieved in aqueous suspension in the presence of nanodimensional alumina and FeCl₃ as oxidant. The resultant composite was found to contain both polythiophene (PTP) and poly(N‐vinylcarbazole) (PNVC) components even after reflux in benzene, which would remove any PNVC homopolymer. The presence of the individual polymer components was endorsed by FTIR spectroscopic analyses. Thermogravimetric analyses showed that the overall stabilities of the composite and the corresponding homopolymers were in the order: PTP–Al₂O₃ > PTP > PTP–PNVC–Al₂O₃ > PNVC. Differential thermal analyses studies showed the manifestation of two different exotherms corresponding to the presence of two different polymeric constituents in the PTP–PNVC–Al₂O₃ composite. Differential scanning calorimetry studies revealed two glass‐transition temperatures (T_g) suggesting the presence of two polymeric moieties in the PTP–PNVC composite. Scanning electron micrographs of the PTP–Al₂O₃ and PTP–PNVC–Al₂O₃ composites showed distinctive morphological patterns. Transmission electron microscopic images of the composite revealed that the average particle size varied between 20 and 80 nm. DC conductivities of the composites were of the order of 10^?6 S cm^?1. Copyright © 2003 Society of Chemical Industry     

A computational and experimental study on the effective properties of Al2O3‐Ni composites

It has been demonstrated that effective medium approximation and mean field homogenization technique is a useful computational tool to predict the effective thermal and structural properties of alumina‐nickel (Al₂O₃‐Ni) composites. Nickel particle size and volume fraction, thermal interface resistance and porosity are found significant factors that affect thermal conductivity, elastoplastic behavior, elastic modulus and thermal expansion coefficient of Al₂O₃‐Ni composite. To complement the computational design, Al₂O₃‐Ni composite samples with designed range of volume fractions and nickel particle size are developed using spark plasma sintering process and properties are measured for model verification.     

Poly(L‐lactide). X. Enhanced surface hydrophilicity and chain‐scission mechanisms of poly(L‐lactide) film in enzymatic,alkaline, and phosphate‐buffered solutions

Attempts were carried out to enhance the surface hydrophilicity of poly(L ‐lactide), that is, poly(L ‐lactic acid) (PLLA) film, utilizing enzymatic, alkaline, and autocatalytic hydrolyses in a proteinase K/Tris–HCL buffered solution system (37°C), in a 0.01N NaOH solution (37°C), and in a phosphate‐buffered solution (100°C), respectively. Moreover, its chain‐scission mechanisms in these different media were studied. The advancing contact‐angle (θ_a) value of the amorphous‐made PLLA film decreased monotonically with the hydrolysis time from 100° to 75° and 80° without a significant molecular weight decrease, when enzymatic and alkaline hydrolyses were continued for 60 min and 8 h, respectively. In contrast, a negligible change in the θ_a value was observed for the PLLA films even after the autocatalytic hydrolysis was continured for 16 h, when their bulk M_n decreased from 1.2 × 10⁵ to 2.2 × 10⁴ g mol^?1 or the number of hydrophilic terminal groups per unit weight increased from 1.7 × 10^?5 to 9.1 × 10^?5 mol g^?1. These findings, together with the result of gravimetry, revealed that the enzymatic and alkaline hydrolyses are powerful enough to enhance the practical surface hydrophilicity of the PLLA films because of their surface‐erosion mechanisms and that its practical surface hydrophilicity is controllable by varying the hydrolysis time. Moreover, autocatalytic hydrolysis is inappropriate to enhance the surface hydrophilicity, because of its bulk‐erosion mechanism. Alkaline hydrolysis is the best to enhance the hydrophilicity of the PLLA films without hydrolysis of the film cores, while the enzymatic hydrolysis is appropriate and inappropriate to enhance the surface hydrophilicity of bulky and thin PLLA materials, respectively, because a significant weight loss occurs before saturation of θ_a value. The changes in the weight loss and θ_a values during hydrolysis showed that exo chain scission as well as endo chain scission occurs in the presence of proteinase K, while in the alkaline and phosphate‐buffered solutions, hydrolysis proceeds via endo chain scission. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1628–1633, 2003     

Mechanism of Nanovoid Formation at the ZnO–Glass Interface in Planar Multilayered Structures of AlOx–ZnO–Glass

Functional porous materials require easy fabrication methods with controllability of a wide range of pore size and its density for practical applications including optical devices. The Kirkendall effect based on unbalanced material diffusion provides such a possibility in conjunction with material configurations of multilayers. This study reports a formation of nanoscale pores within ZnO films in planar multilayered structures of Al₂O₃–ZnO‐aluminosilicate glass and demonstrates the mechanism of forming relatively large nanopores in ZnO near the ZnO–glass interface via stress‐promoted Kirkendall diffusion. Experimental characterizations supported by atomic simulation reveal that an enhanced in‐plane tensile stress in the ZnO films with increasing the thickness of the neighboring Al₂O₃ films can promote the diffusivity of the Zn atoms and the pore growth in the ZnO films. The pore size and location in the intermediate ZnO layer of the Al₂O₃–ZnO–glass is alterable by simply selecting the thickness of the Al₂O₃ layer. Promoted diffusion of the Zn atoms enables to fabricate porous planar ZnO films with pore sizes up to a few hundred nm with an enhanced light scattering ability. These findings offer a promising route to produce porous planar films through in‐depth understanding of diffusivity enhancement in glass–metal oxide couples.     

Separation of bovine serum albumin (BSA) using γ‐Al2O3–clay composite ultrafiltration membrane

BACKGROUND: Ceramic membranes have received more attention than polymeric membranes for the separation and purification of bio‐products owing to their superior chemical, mechanical and thermal properties. Commercially available ceramic membranes are too expensive. This could be overcome by fabricating membranes using low‐cost raw materials. The aim of this work is to fabricate a low‐cost γ‐Al₂O₃–clay composite membrane and evaluate its potential for the separation of bovine serum albumin (BSA) as a function of pH, feed concentration and applied pressure. To achieve this, the membrane support is prepared using low‐cost clay mixtures instead of very expensive alumina, zirconia and titania materials. The cost of the membrane can be further reduced by preparing a γ‐alumina surface layer on the clay support using boehmite sol synthesized from inexpensive aluminium chloride instead of expensive aluminium alkoxide using a dip‐coating technique. RESULTS: The pore size distribution of the γ‐Al₂O₃‐clay composite membrane varied from 5.4–13.6 nm. The membrane was prepared using stable boehmite sol of narrow particle size distribution and mean particle size 30.9 nm. Scanning electron microscopy confirmed that the surface of the γ‐Al₂O₃–clay composite membrane is defect‐free. The pure water permeability of the support and the composite membrane were found to be 4.838 × 10^?6 and 2.357 × 10^?7 m³ m^?2 s^?1 kPa^?1, respectively. The maximum rejection of BSA protein was found to be 95%. It was observed that the separation performance of the membrane in terms of flux and rejection strongly depends on the electrostatic interaction between the protein and charged membrane. CONCLUSION: The successively prepared γ‐Al₂O₃‐clay composite membrane proved to possess good potential for the separation of BSA with high yield and could be employed as a low cost alternate to expensive ceramic membranes. Copyright © 2009 Society of Chemical Industry     

Scratch behavior of nanoparticle Al2O3-filled gelatin films

Nanoscale alumina/protein gel composite films with 10–50 wt% filler were subjected to scratch testing and compared to micron-scale alumina/protein gel composites. Atomic force microscopy (AFM) was employed to examine the width, depth, and morphology of the as-produced scratches. The results show that the scratch depth in gelatin films and the tearing within the scratch decrease dramatically with the addition of the nanoscale (average particle size, 13 nm) alumina fillers. It was found that refining the particle size distribution of the Al₂O₃ powder (average particle size, 10 nm, with no particles larger than 70 nm) further reduced the scratch depth and width, while improving the dimensional integrity and surface roughness of the nanocomposites. Aging of the gelatin films improved the intrinsic scratch resistance of both filled and unfilled gelatin films. In comparison, micron-size Al₂O₃ filler not only increased the scratch width, but also resulted in poor particle dispersion and low transparency of the films. The optical clarity of the nanofilled composites was much higher than that of the composites with micron-size filler.     

Colored films produced by electron beam deposition from nanometric TiO2 and Al2O3 pigment powders obtained by modified polymeric precursor method

Synthesis and the characterization of TiO₂:5%Co (green), TiO₃:5%Fe (brown-reddish), TiO₂:2%Cr (brown), Al₂O₃:5%Co (blue), Al₂O₃:5%Fe (brown-reddish) and Al₂O₃:2%Cr (light green) nanometric pigment powders using polymeric precursor (modified Pechini's method) is reported. Colored thick films were deposited on amorphous quartz substrates by electron beam physical vapor deposition (EB-PVD) using pellets of the pigment powders as target. The evaporation process was carried out in vacuum of 4 × 10⁻⁶ Torr and the amorphous quartz substrates were kept at 350 °C during deposition. The TiO₂-based pigment powders presented crystalline anatase phase and the Al₂O₃-based pigment powders showed corundum phase, investigated by X-ray diffraction (XRD). The average particle size of the pigment powders was about 20 nm, measured by scanning electron microscopy with field emission gun (SEM-FEG). Diffuse reflectance spectra and colorimetric coordinates L¹, a¹, b¹ using the CIE-L¹a¹b¹ method are shown for the pigment powders, in the 350–750 nm range. The colored thick films were characterized by transmittance (UV–Vis) and atomic force microscopy (AFM). The average film roughness was ∼5.5 nm and the average grain size obtained in the films was around 75 nm. Films with thickness from 400 nm to 690 nm were obtained, measured by talystep profiler. Transmission spectra envelop method has been used to obtain refractive index and thickness of the Al₂O₃ colored thick films.