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TiO2 nanorod arrays (NRAs) with 540 nm length and an amorphous porous structure, were fabricated by oblique angle deposition method. The as-prepared amorphous TiO2 NRAs transform gradually into anatase phase after annealing with a temperature higher than 350 °C, whereas the specific surface area decreases due to the better crystallinity. The intensity of hydroxyl groups increases with enhancing annealing temperature, then decreases above 450 °C. The photocatalytic and photo-conversion properties benefit from the high crystallinity of TiO2 NRAs and high density of hydroxyl groups on the surface. It shows that TiO2 NRAs annealed at 450 °C exhibit the highest photoconversion efficiency and maximum degradation rate of MO, which can be ascribed to the excellent crystallization and the optimum density of hydroxyl groups on the surface of TiO2. The TiO2 NRAs with enhanced crystallinity and fine structures are very promising for photocatalyst materials for environmental protection.

The current paper discusses the preparation of novel Fe-coated carbon fiber (CF@Fe) composites using metal organic chemical vapor deposition (MOCVD) for use as microwave absorbing materials. SEM, EDS, and XRD studies show that the MOCVD method can produce a uniform coating of iron on the CFs. Compared with common CF, the CF@Fe composites have higher resistivity and magnetic loss, which gradually increase with increasing iron content. At an CF@Fe weight fraction of 8 %, the minimum reflection loss (RL) is −38 dB at 13.4 GHz and a corresponding thickness of 2.5 mm. An RL exceeding −10 dB is obtained in the frequency range of 8–15 GHz and a thickness of 1.5–3.0 mm. The results indicate that the prepared composite has excellent electromagnetic absorption properties with lightness.

In this paper, we propose a nanostructure with Au nanoparticles (NPs), as electron sinks, located at the most outside layer of CdS sensitized TiO2 nanorod arrays (TiO2 NRAs/CdS/Au). By the introduction of Au NPs, TiO2 NRAs/CdS/Au performs higher visible light photocatalytic capacity in the degradation of unsymmetrical dimethylhydrazine wastewater than TiO2 NRAs/CdS. The optimal deposition time for Au NPs is 30 s. The visible light induced degradation ability of TiO2 NRAs/CdS/Au (30 s) is 1.4 times that of TiO2 NRAs/CdS. The cycling stability of TiO2 NRAs/CdS is greatly enchanced after Au NPs decoration, which can maintain 95.86% after three cycles. Photoluminescence spectra and photoelectrochemical measurements were carried out to reveal the underlying mechanism for the improved visible light photocatalytic capacity of TiO2 NRAs/CdS/Au. This work demonstrates a promising way for the rational design of metal-semiconductor photocatalysts used in decomposition reaction that can achieve high photocatalytic efficiency.

The spinel ferrite (AFe2O4, A=Ni, Zn, Mn) were prepared under the same condition via sol–gel method. The structure and electromagnetic properties of the powders were characterized by X-ray diffractometer, scanning electron microscope, and vector network analyzer, respectively. These materials were found to be very good catalysts for the oxidation of styrene to benzaldehyde in the presence of hydrogen peroxide. Because of the difference in radius and electrical of these ions (Ni2+, Zn2+ and Mn2+), the ion distribution of ferrites were diverse, so that the electromagnetic parameters and absorbing properties varied. After analyze the contour map of the attenuation constant α and reflectivity R, it shows that the absorbing weak point of NiFe2O4 lies in the high frequency range 8-14GHz ,the absorbing properties of MnFe2O4 is relatively balanced, and the absorbing capacity of ZnFe2O4 in the high-frequency part is poor. NiFe2O4, MnFe2O4 and ZnFe2O4 in absorbing band complement each other very well. By preparing an appropriate proportion of Ni-Mn-Zn composite spinel ferrite, an excellent absorbing agents will be expected.

The microwave absorption properties of carbonyl iron (CI) and CoFe 2 O 4 ferrite with single-layer and double-layer composite absorbers were investigated based on the electromagnetic transmission line theory and the impedance matching principle in the frequency range from 2 GHz to 18 GHz. XRD and SEM were used to characterize the structure of the powdered composites. Coaxial method was used to measure the electromagnetic parameters of CI and CoFe 2 O 4 . The reflectances of the matching and absorbing layers of different thicknesses and orders were also calculated. The results show that using CoFe 2 O 4 as matching layer and CI as absorbing layer can greatly expand the coating absorption bandwidth and decrease the reflectance peak. Double-layer absorbers have much better microwave absorption properties than single-layer absorbers. The microwave absorption properties of the double-layer structure are influenced by the coupling interactions between the absorbing and matching layers. The double-layer microwave absorbers with reflection loss less than −10 dB over the range from 8.6 GHz to 18 GHz (the absorption bandwidth is 9.4 GHz), which almost covers the X-band (8.2 –12.4 GHz) and the whole Ku-band (12.4–18 GHz) were achieved when the thicknesses of CoFe 2 O 4 and CI were 2.4 and 0.5 mm, respectively.

In this paper, we propose a nanostructure with Au nanoparticles (NPs), as electron sinks, located at the most outside layer of CdS sensitized TiO2 nanorod arrays (TiO2 NRAs/CdS/Au). By the introduction of Au NPs, TiO2 NRAs/CdS/Au performs higher visible light photocatalytic capacity in the degradation of unsymmetrical dimethylhydrazine wastewater than TiO2 NRAs/CdS. The optimal deposition time for Au NPs is 30 s. The visible light induced degradation ability of TiO2 NRAs/CdS/Au (30 s) is 1.4 times that of TiO2 NRAs/CdS. The cycling stability of TiO2 NRAs/CdS is greatly enchanced after Au NPs decoration, which can maintain 95.86% after three cycles. Photoluminescence spectra and photoelectrochemical measurements were carried out to reveal the underlying mechanism for the improved visible light photocatalytic capacity of TiO2 NRAs/CdS/Au. This work demonstrates a promising way for the rational design of metal-semiconductor photocatalysts used in decomposition reaction that can achieve high photocatalytic efficiency.

Photocatalysis technology could utilize solar energy to degrade many toxic pollutants and provides possibility to deal with unsymmetrical dimethylhydrazine (UDMH) wastewater with less energy consumption. In this study, well-aligned TiO2 nanorod arrays (TiO2 NRAs) were grown directly on transparent conductive glass (FTO) via a hydrothermal method, and TiO2 NRAs/CdS heterostructure films were prepared by decorating TiO2 NRAs with CdS nanoparticles through successive ion layer adsorption and reaction (SILAR). Under visible light, the TiO2 NRAs/CdS heterostructure displays enhanced photodegrading capacity compared with the bare TiO2 NRAs, and the highest photodegradation rate, 27.5% higher than that of the bare TiO2 NRAs, was achieved by the sample with 15 SILAR cycles. Additionally, the solution pH had some influence on the degradation process, which shows that the best degradation rate can be achieved in the neutral solution (pH is ca. 7.2), and the photodegradation process can be better in alkaline solution than in the acid solution. Moreover, the visible photocatalytic stability of the TiO2 NRAs/CdS sample was investigated. Finally, the underlying photocatalytic mechanism was discussed according to the photoelectrochemical and photoluminescence results. Electronic supplementary material The online version of this article (doi:10.1186/s11671-016-1718-9) contains supplementary material, which is available to authorized users.

Modified TiO2 nanomaterials are considered to be promising in energy conversion and ferrites modification may be one of the most efficient modifications. In this research, various ferrites, incorporated with various cations (MFe2O4, M = Ni, Co, Zn and Sr), are utilized to modify the well aligned TiO2 nanorod arrays (NRAs), which is synthesized by hydrothermal method. It is found that all MFe2O4/TiO2 NRAs show obvious red shift into the visible light region compared with the TiO2 NRAs. In particular, NiFe2O4 modification is demonstrated to be the best way to enhance the photoelectrochemical and photocatalytic activity of TiO2 NRAs. Furthermore, the separation and transfer of charge carriers after MFe2O4 modification are clarified by electrochemical impedance spectroscopy measurements. Finally, the underlying mechanism accounting for the enhanced photocatalytic activity of MFe2O4/TiO2 NRAs is proposed. Through comparison among different transition metals modified TiO2 with the same synthesis process and under the same evaluating condition, this work may provide new insight in designing modified TiO2 nanomaterials as visible light active photocatalysts.

Shell-core Fe–Sr0.8La0.2Fe11.8Co0.2O19 composites are prepared by chemical vapor deposition (CVD) for use as microwave absorbing materials. Scanning electron microscopy and X-ray diffraction analyses show that the CVD method yields Sr0.8La0.2Fe11.8Co0.2O19 powders with a uniform coating of Fe. Compared with Sr0.8La0.2Fe11.8Co0.2O19, Fe–Sr0.8La0.2Fe11.8Co0.2O19 composites have higher electrical conductivity, permittivity, and dielectric loss, which gradually increase with increasing Fe content. When Sr0.8La0.2Fe11.8Co0.2O19/Fe=7:3, a reflection loss (RL) exceeding −10 dB is obtained in the frequency range of 10–14 GHz at a coating thickness of 2.0 mm. A minimum RL of −30 dB was found at 8.0 GHz, corresponding to a matching thickness of 2.8 mm.

Nd–Co-substituted M-type strontium hexaferrites were prepared by sol–gel-autocombustion method. Crystalline structure, morphology, magnetic properties, and microwave absorption properties of Sr 1− x Nd x Fe 12− x Co x O 19 ( x = 0–0.4) were studied via X-ray diffraction, scanning electron microscope, vibrating sample magnetometer, and vector network analyzer, respectively. Single-phase M-type strontium hexaferrites, with a chemical composition of Sr 1− x Nd x Fe 12− x Co x O 19 ( x = 0–0.3), were formed by being heated at 1200 ˚C for 3 h in air. Saturation magnetization and coercivity reached a maximum at x = 0.2. For samples with x = 0.2, a minimum reflection loss of −22 dB was obtained at 16.2 GHz for a layer of 1.9 mm in thickness. The reflection loss of Sr 0.8 Nd 0.2 Fe 11.8 Co 0.2 O 19 ferrite (1.5–3.0 mm in thickness) is less than −10 dB over the range of 9.8–18 GHz. It indicates that the substituted Nd–Co can greatly improve the microwave absorption properties of SrFe 12 O 19 hexaferrites.

This study was based on the purpose of investigating the reaction rules of formaldehyde (HCHO) as an intermediate product in the degradation of many other organic wastewaters. The process conditions of UV-Fenton method for the degradation of the low concentrations of HCHO were studied in a batch photochemical reactor. The results showed that, when the original HCHO concentration was 30 mg/L, at an operating temperature of 23 degrees C, pH = 3, an H202 dosage of 68 mg/L, and an H2O2-to-Fe2+ mole ratio (H2O2:Fe2+) of 5, 91.89% of the HCHO was removed after 30 minutes. The degradation of HCHO in the UV-Fenton system was basically in accordance with the exponential decay. The kinetic study results showed that the reaction orders of HCHO, Fe2+, and H2O2 in the system were 1.054, 0.510, and 0.728, respectively, and the activation energy (Ea) was 9.85 kJ/mol. The comparison of UV/H2O2, Fenton, and UV-Fenton systems for the degradation of HCHO, and the results of iron catalyst tests showed that the mechanism of UV-Fenton on the degradation of HCHO was through a synergistic effect of Fe2+ and UV light to catalyze the decomposition of H2O2. The introduction of UV irradiation to the Fenton system largely increased the degradation rate of HCHO, mainly as a result of the accelerating effect on the formation of the Fe2+/Fe3+ cycle. The reaction products were analyzed by gas chromatography-mass spectrometry and a chemical oxygen demand (COD) analyzer. The effluent gases also were analyzed by gas chromatography. Based on those results, the reaction pathways of HCHO in the UV-Fenton system were proposed. The qualitative and quantitative analysis of the reaction products and the COD showed that the main intermediate product of the reaction was formic acid, and the further oxidation of it was the rate-limiting step for the degradation of HCHO.

An absorbing medium is prepared using nanosize carbon black (CB) blended with nanosize silicon carbide (SiC). The medium improves the wave absorption properties and the wave band of the single CB absorbent. The microstructure, conductivity, dielectric property, and microwave absorption of the material are studied by means of field emission scanning electron microscopy, trielectrode method, and vector network analyzer respectively. The results show that SiC can reduce the percolation threshold of CB/epoxide resin composite. Addition of certain mass of SiC can improve the microwave absorption of the composite. When 5 wt.% carbon black is blended with 50 wt.% SiC to fabricate a composite with a 2 mm thickness, the maximum reflection loss becomes −41 dB at 9 GHz, and the −10 dB bandwidth reaches 6 GHz. Thus, the prepared composite has the potential for use in electromagnetic absorption.

The influence of interface effect between inclusion particles and matrix in composite on electromagnetic wave absorbing characteristics has been investigated. Firstly, an effective permittivity model of composite with interfacial shell is established. And then the formula for the effective permittivity and permeability of composite with interface is derived based on the effective medium theory. According to the proposed formula and transmission line theory, the influence of the interface effect on the electromagnetic wave absorption characteristics is discussed. The size effect of the inclusion on the reflection loss of absorbing composite is also studied. All these results indicate that the interface effect of inclusion particle should be considered in design and application of the electromagnetic wave absorbing composites when the size of the filler particles is in micron range.

The toxic transformation products of hydrazines are of great concern. These products&rsquo, properties combined with their formation mechanisms are needed to assess their potential environmental and human impacts. In this study, the gas-phase reaction of hydrazine (N2H4), monomethyldrazine (MMH) and unsymmetrical dimethyhydrazine (UDMH) with O3 have been studied at varying reactant ratios, both in the presence and absence of a radical trap. Gas chromatography-mass spectroscopy (GC-MS) has been implied to follow reactant consumption and product formation. Apart from the reported products detected by Fourier transform infrared spectroscopy (FT-IR), the newly found compounds (hydrazones, formamides, dimethylamine, 1,1,4,4-tetramethyl-1,2-tetrazene,dimethylamino-acetonitrile, N2, H2O, et al.) are identified by GC-MS. The relative yields of the organic products vary considerably at different O3/MMH or UDMH ratios. UDMH and MMH are confirmed as high potential precursors of N-nitrosodimethylamine (NDMA). The presence of hydroxyl radicals (HO&middot, ) hinders NDMA formation in MMH-O3 system. Meanwhile, it increases NDMA formation in UDMH-O3 system. The suggested reaction mechanisms which account for the observed products are discussed.

An effective permittivity model of composite with interfacial shell is established. The concentric core–shell ellipsoidal particle randomly mixed with matrix is replaced by solid particle mixed with the same matrix, and the equivalent solid particle has the same radius as the original coating shell. Based on the effective medium theory, the formula for the effective permittivity of two-phase composite with interface is derived, then a simple self-consistent method is applied to modify the formula. With the modified formula, the influence of the structure parameter, the permittivity of the shell, the shape and the volume content of the core on the effective permittivity are investigated. The theoretical results on the effective permittivity of polystyrene–barium titanate composites with interfaces are in agreement with the experimental data.

The Ni–P–CB (carbon black) nanocomposite coatings have been successfully deposited on an ABS plastic matrix via electroless plating process. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) spectrometry techniques were employed to examine the surface morphology and structure of the as-plated coating. Energy dispersive spectroscopy (EDS) was adopted to obtain the component analysis of the Ni–P–CB composite coating, and the infrared emissivity of the coating was determined by the IRE-I Infrared Emissometer. SEM and XRD results indicated that the nanoparticles were dispersed homogeneously in the Ni–P coating; the result of EDS showed that the increased rate of CB content is in correspondence with its concentration. In the case that CB concentration is lower than 4 g/L, the increase rate is sharp, whereas when the concentration is higher than 4 g/L, the increase rate is reduced significantly. Furthermore, study of infrared emissivity shows that the nanocomposite coatings possessed low emissivity value. A comparison of the infrared emissivity dependence on surface resistivity obtained from the analysis of the experimental results and those calculated using the Hagen–Rubens relation indicates that the Hagen–Rubens relation is good for modeling the infrared emissivity of the Ni–P–CB nanocomposite coatings.

Two permeable chemical protective clothing sets (clothing system 1 and clothing system 2) were tested in a hot temperature environment, in order to study the influence factors of clothing comfort. Methods: Using the sweating guarded hotplate and thermal manikin, two methods to measure are thermal resistance (Rct) and water-vapor resistance (Ret) values of the two clothing systems. Results: In sweating guarded hotplate test, clothing system 1 Rct11 is 14.51 × 10-3 m2K/W and the Ret11 is 6.87 m2Pa/W, clothing system 2 Rct21 is 22.62 × 10-3 m2K/W and the Ret21 is 10.28 m2Pa/W; in thermal manikin test, clothing system 1 Rct12 is 9.62 × 10-3 m2K/W and the Ret12 is 5.08 m2Pa/W, clothing system 2 Rct22 is 14.21 × 10-3 m2K/W and the Ret22 is 8.36 m2Pa/W. Conclusion: The air gap is the main factor which leads to the different results between two test methods. Optimization of chemical protective clothing structural design can effectively promote the clothing heat dissipation, which has a positive effect on the comfort and safety of chemical protective clothing.

TiO2 nanorod arrays (TiO2 NRAs) sensitized with CdS nanoparticles were fabricated via successive ion layer adsorption and reaction (SILAR), and TiO2 NRAs were obtained by oxidizing Ti NRAs obtained through oblique angle deposition. The TiO2 NRAs decorated with CdS nanoparticles exhibited excellent photoelectrochemical and photocatalytic properties under visible light, and the one decorated with 20 SILAR cycles CdS nanoparticles shows the best performance. This can be attributed to the enhanced separation of electrons and holes by forming heterojunctions of CdS nanoparticles and TiO2 NRAs. This provides a promising way to fabricate the material for solar energy conversion and wastewater degradation.

The polymerization of a bismaleimide (BMID) monomer and five N-substituted maleimide monomers have been carried out in N , N -dimethyl formamide (DMF) at 155±2°C, initiated by nanometer sized Na + /TiO 2 . The polymer of BMID can also be prepared, with nanometer sized Na + /TiO 2 as the initiator, in dimethyl sulfoxide (DMSO), cyclohexanone and epoxy chloropropane, but not in toluene. The structures and thermal properties of the resulting polymers were characterized by FT-IR, 1 H-NMR, UV–VIS spectrophotometer and TGA, etc.

N-doped TiO2nanorod arrays (NRAs) were prepared by annealing the TiN nanorod arrays (NRAs) which were deposited by using oblique angle deposition (OAD) technique. The TiN NRAs were annealed at 330°C for different times (5, 15, 30, 60, and 120 min). The band gaps of annealed TiN NRAs (i.e., N-doped TiO2NRAs) show a significant variance with annealing time, and can be controlled readily by varying annealing time. All of the N-doped TiO2NRAs exhibit an enhancement in photocurrent intensity in visible light compared with that of pure TiO2and TiN, and the one annealed for 15 min shows the maximum photocurrent intensity owning to the optimal N dopant concentration. The results show that the N-doped TiO2NRAs, of which the band gap can be tuned easily, are a very promising material for application in photocatalysis.

TiO2 nanorod arrays (TiO2 NRAs) decorated with CdS nanoparticles (CdS NPs) were fabricated via successive ion layer adsorption and reaction (SILAR), and TiO2 NRAs were obtained by oxidising Ti NARs obtained through oblique angle deposition (OAD) by magnetron sputtering. The TiO2 NRAs decorated with CdS NPs exhibited excellent visible light photoelectrochemical and photocatalytic properties, and the one decorated with 20 SILAR cycles CdS NPs plays the best performance. This can be attributed to the enhanced electrons-holes generation and separation by forming hetero-junctions of CdS NPs and TiO2 NRAs. It provides a promising way to fabricate the material applied in the solar energy conversion and waste water degradation.

The UV-Fenton treatment of formaldehyde (HCHO) was studied in a batch photochemical reactor. This is based on the purpose to reveal the reaction rules of HCHO as an intermediate product in the degradation of many other kinds of organic wastewater. The oxidation course can be divided into rapid reaction stage, transition stage and slow reaction stage. The effects of Fe2+, H2O2 concentration and the pH on the HCHO removal were studied in various conditions. 91.89% of the HCHO removal was obtained within 30 minutes in the presence of 22.4 mg/L of Fe2+, 64 mg/L of H2O2, pH 3 and a temperature of 23°C. Through using the first order kinetic model by stages, it indicates that the rate constants of the rapid reaction stage are much greater than the slow reaction stage. The activation energies in the two stages are respectively 7.49 and 13.49 kJ·mol-1. The temperature coefficient of the UV-Fenton reaction is small. But in the slow reaction stage of the reactions, the temperature has higher influence on the reaction velocity and begins to have minus effects for the HCHO degradation when it is above 40°C.

This study was performed to further reveal the reaction mechanism and kinetic characters of UV-Fenton process for the degradation of formaldehyde (HCHO) in a batch photochemical reactor. The concentration changes of hydrogen peroxide, ferrous ions, and the intermediate products were analyzed. Through comparing the rate constants (k) of H2O2 consumption and the variation of Fe2+ concentration in the UVH2O2, Fenton and UV-Fenton processes, it indicates that the Fe2+ and the UV light has a synergistic effect for the degradation of HCHO in the UV-Fenton system. The introduction of UV accelerates the reduction of Fe3+, and makes the cycle of iron obtain more paths. The products in the UV-Fenton reaction were analyzed by a gas chromatography-mass spectrometry and a chemical oxygen demand analyzer. Based on the results, the reaction pathways of HCHO degradation in the UV-Fenton system were proposed. The rate constants of the two consecutive first-order reactions in the degradation of HCHO are respectively k1 = 0.543 min-1 and k2 = 0.045 min-1. The mineralizing of formic acid is the rate-controlled step of the reaction.

In photochemical reactor, the process conditions of formaldehyde wastewater treatment using UV-Fenton oxidation under the joint action of hydrogen peroxide, ferrous ions, and ultraviolet were studied, and the kinetic curves of formaldehyde degradation in different conditions were obtained. The results showed that: when the original wastewater concentration is 30mg/L, operating temperature is 23 ℃, pH = 3, the dosage of H2O2 is suitable for 68mg/L (correspond to the theoretic oxygen requirement of wastewater 1Qth), H2O2 and Fe2+ dosing ratio n(H2O2) ∶n (Fe2+) = 5, reaction to 30 minutes, the removal rate of formaldehyde is up to 91.89%. On this basis, the kinetic model for formaldehyde wastewater treatment in UV-Fenton system was established. By curve fitting and equation solving, the kinetic equation was obtained as follow: r=-d[HCHO]/dt=2.788×10-2[HCHO]0.574[Fe2+]0.51[H2O2]0.728. The analysis of reaction products by UV spectrum supposed that the further oxidation of the intermediate product, formic acid, is the rate-limiting step of formaldehyde oxidation reaction.

Epoxy (EP) was filled with nano-carbon black(CB) and micron SiC. The effects of CB and SiC fraction on the absorbing properties of the EP composites were studied. The structure and morphology of the samples were characterized by scanning electron microscopy (SEM). The spectroanalysis indicates that the absorbent particles are dispersed uniformly in the coating. At 8 ~ 18GHz, for composite coating with 1.05mm thickness, the absorbing bandwidth less than -5dB is 7.7GHz and less than -8dB is 4.6GHz, and the most reflection loss can reach -19.27dB. With the increase thickness of the coating, the absorbing peak value moves to the lower frequency. The bandwidth and the wave absorbing peak values increase along with the increasing of the content of CB filling fraction. And the absorbing mechanism of the composite was also discussed.

TiO2 nanorod arrays (TiO2 NRAs) sensitized with CdS nanoparticles were fabricated via successive ion layer adsorption and reaction (SILAR), and TiO2 NRAs were obtained by oxidizing Ti NRAs obtained through oblique angle deposition. The TiO2 NRAs decorated with CdS nanoparticles exhibited excellent photoelectrochemical and photocatalytic properties under visible light, and the one decorated with 20 SILAR cycles CdS nanoparticles shows the best performance. This can be attributed to the enhanced separation of electrons and holes by forming heterojunctions of CdS nanoparticles and TiO2 NRAs. This provides a promising way to fabricate the material for solar energy conversion and wastewater degradation.

TiO2-TiN composite catalysts were prepared by oxidizing the TiN films in air at 350 °C. By adjusting the oxidation time to control the oxidation stage of TiN films, the optical band gap of the TiO2-TiN composites can be varied in a wide range from 1.68 eV to 3.23 eV. These composite films all showed red shift in photo-response towards the visible region, and depending on the optical band gap, some composite films exhibited good catalytic activity in the visible light region. This study provides a simple but effective method to prepare film photocatalyst working in visible light.

A unique model for predicting the effective permittivity of a filler/polymer composite system with an interphase is presented. In order to take into account the interactions between the filler and the matrix as well as filler–filler overlapping, a microscopic modification is introduced into the interphase volume fraction as a function of filler concentration. The proposed model shows that the effective permittivity relies on the volume fractions of the filler phase, the matrix phase and the interphase region as well as the permittivity of each phase. This model also provides a means to determine the volume and permittivity of the interphase in a composite by fitting the experimental data. Based on the present model, the effects of filler concentration, filler size, volume and permittivity of the interphase region on the effective permittivity of the composite are investigated. The theoretical results of the proposed model on filler/polymer composites are in agreement with experimental data.

Nanostructured titanium nitride (TiN) films with varying porosity were prepared by the oblique angle deposition technique (OAD). The porosity of films increases as the deposition angle becomes larger. The film obtained at an incident angle of 85° exhibits the best catalytic activity and sensitivity to hydrogen peroxide (H2O2). This could be attributed to its largest contact area with the electrolyte. An effective approach is thus proposed to fabricate TiN nanostructure as H2O2 sensor by OAD.