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The sol-gel method has been employed in the fabrication of mesoporous composite films consisting of a nonionic surfactant, Pluronic P123, as the organic component, and silica as the inorganic component. The hybrid nature of these films resulted in their having an internal structure consisting of nanometer size self-assembled organic mesostructures surrounded by a silica framework. These films served as the host matrix for the laser dye coumarin 481 (C481) and an energy transfer complex formed between C481 and J-aggregated meso-tetra(4-sulfonatophenyl)porphyrin (TSPP). Upon exposure to methanol vapor, a rapid and reversible decrease in fluorescence intensity occurs for films containing C481 alone as well as containing both C481 and TSPP. Steady-state and time-resolved spectroscopic studies suggest that the decrease in fluorescence intensity is primarily due to an excited state interaction between methanol and C481; while, additionally, morphological changes within the film appear to play a role for films containing both C481 and TSPP.

Zinc oxide whisker arrays well-aligned along [0001] direction have been grown on the substrates of glass and single crystal silicon by atmospheric metal organic chemical vapor deposition method (MOCVD). The SEM observation indicated that the whiskers were quite uniform in length and diameter. The whisker arrays were very dense, and the gap among the whiskers was less than 1 μm. The array materials were proposed as the component to prepare 1-3 piezoelectric composite film in-situ. Epoxy resin was used as the matrix materials. The key points to prepare the composites are how to make the resin enter the array and control a suitable thickness of the resin films. Several approaches were studied. The results showed that the best was the vertical sucking method. The SEM observations indicated that the thickness was well controlled as almost same as the length of the whiskers, and the resin perfectly entered the array without pore. The 1-3 piezoelectric composite film has great potential applications in micro sensor and actuator arrays.

The present work describes the preparation characterization and electrical conductivity measurement of carbon–nitrogen (C–N) nanotubes–PEO composites films. CNNTs–PEO composite films have been prepared by using the solution cast technique and characterized by scanning electron microscope (SEM PHILIPS XL-20). The DC electrical conductivity measurements of the composite films revealed that for PEO film conductivity has been found to be ~ 7.5 × 10^-8 Scm^-1, and for C–N nanotubes (~ 20 wt.%)–PEO film it was found to be ~6.2 Scm^-1 at room temperature. Thus, compared to the PEO film, the conductivity of the C–N nanotubes (~ 20 wt.%)–PEO composite film is eight orders of magnitude higher. The same conductivity of ~ 6.2 Scm^-1 for the carbon nanotubes (CNT)–PEO composites comes out at 50 wt.% of CNT in PEO as reported earlier by our group. The conductivity increases with the increase of temperature, confirming the semiconducting nature of the C–N nanotubes–PEO composites.

SnO₂/MgO composite film-based dye-sensitized solar cells (DSCs), sensitized with both N719 dye and metal-free D358 dye, employing redox couple-based liquid electrolyte, show superior performance to those sensitized with only D358 dye, and N719 dye. A significant improvement in the power conversion efficiency was attained by co-sensitizing the N719-based DSCs with metal-free D358 dye when compared to those obtained for DSCs with individual dyes. As confirmed by UV-visible absorption spectra, N719 dye adsorption is more prominent than that of D358 dye when sensitizing the SnO₂/MgO composite film with the two dyes, D358 and N719. However, N719 and D358 dyes, when used alone, are prone to form aggregates on the SnO₂/MgO composite film, when N719 dye is used together with D358, the latter effectively suppresses the aggregation of N719 dye on the SnO₂/MgO composite film, thereby enhancing the power conversion efficiency of the DSCs. Hence, the corresponding power conversion efficiency of the SnO₂/MgO composite film-based DSCs can be significantly improved by sensitizing with both N719 and D358 dyes. The reported power conversion efficiencies for the SnO₂/MgO composite film-based DSCs, sensitized with, (a) D358 dye, (b) N719 dye, and (c) both N719 dye and D358 dye, are 6.37%, 7.43% and 8.60% respectively, under AM 1.5 illumination.

New inorganic-organic transparent composite films of the formula (Zn${}_{\mathrm{\text{2}}}$Al-LDH/ZnTPPS)${}_{\mathrm{\text{n}}}$ were fabricated using exfoliated cationic Zn${}_{\mathrm{\text{2}}}$Al layered double hydroxide (Zn${}_{\mathrm{\text{2}}}$Al-LDH) nanosheets and anionic meso-tertra(4-sulfophenyl) zinc porphyrin (ZnTPPS) through an electrostatic layerbylayer self-assembly method. The resulting composite films were characterized by UV-vis spectroscopy (UV-vis) scanning electron microscopy (SEM) and atomic force microscopy (AFM). The results showed that the films have relatively smooth and orderly surfaces, with the large ring plane of the porphyrin molecules vertically aligned LDH nanosheets and can grow in a nearly linear fashion with increasing the deposition cycles. Z-scan measurements, which were conducted under laser irradiation at a wavelength of 532 nm pulse width of 6 ns, repetition rate of 10 Hz and light intensity at focus $E$ of 10 $\mu$J, revealed that the composite films have notable saturation absorption (cf., ZnTPPS in solution shows reverse saturation) and optical nonlinear self-defocusing behavior with the nonlinear optical absorption coefficient $\beta$ refractive index $n_{\mathrm{\text{2}}}$, and third-order NLO susceptibility ${\chi }^{\mathrm{\text{(3)}}}$ of the films increasing with the increase in number of layers of films (${\chi }^{\mathrm{\text{(3)}}}$ value is up to 7.86 × 10${}^{\mathrm{\text{-11}}}$ esu when $n=$ 40), implying the NLO responses could be modified by fine tuning the thickness of composite films.

The well dispersed ZAO nanoparticle with 25–30 nm in diameter was prepared by an ultrasonic-template method. The morphologies, structures, and photoelectricity of the ZAO nanoparticles were analyzed by TEM, XRD, UV-Vis, etc. The thermochemistry behaviors of the precursor were studied by TG-DSC. The composite film with semipermeable structure made from ZAO nanoparticles and collodion can be explored firstly. The photocatalytic properties of the ZAO nanoparticles and composite film were investigated. The composite film can be applied in the sewage treatment field.

BaFe₁₂O₁₉–Ni_0.8Zn_0.2Fe₂O₄/Polypyrrole composite film [including three doping acids, dodecyl benzene sulfonic acid (DBSA), camphor sulfonic acid (CSA) and p-toluenesulfonic acid (TSA)] was prepared by sol–gel method and in situ chemical oxidative polymerization. The structure, morphologies, conductivities, magnetic properties and microwave absorption properties of the composite film were characterized by using XRD, FESEM, FTIR, Four-probe tester, VSM and Vector network analyzer. The results show that the conductivity of acid-doped Polypyrrole composite film is higher than that of pure Polypyrrole composite film. The saturation magnetization (M_s) and remanent magnetization (M_r) of the composite film are lower than those of BaFe₁₂O₁₉–Ni_0.8Zn_0.2Fe₂O₄ film. However, the electromagnetic properties are in the contrary. The microwave absorption properties of the composite film are much better than those of BaFe₁₂O₁₉–Ni_0.8Zn_0.2Fe₂O₄, which mainly depends on the increasing of the dielectric loss. A minimum reflection loss of the DBSA-doped composite film is −17.6 dB at 9.3 GHz with the thickness at 3.0 mm.

The NiO nanocrystalline/reduced graphene oxide (rGO) composite film was successfully synthesized using a simple hot-injection and dip coating method. The as-prepared samples were characterized using X-ray diffraction (XRD), Raman, scanning electron microscope (SEM), ultraviolet and visible spectrophotometer (UV). Compared to the NiO film, the NiO nanocrystalline/rGO composite film exhibits enhanced electrochromic properties and large $\mathrm{\Delta }T$ (40.7% at 550nm), fast switching speed ($t_c=4$.3s and $t_b=3$.9s), high coloration efficiency (12.85cm² C${}^{-1})$ and better cycling performance (1000 cycles). The improvement of the electrochromic properties was attributed to the large specific surface area and good conductivity of the rGO.

There is a demand for composite films with excellent hydrophobic properties in inertial confinement fusion (ICF) physics experiments. In this paper, we prepared fluorinated polyimide hydrophobic films using spinning and plasma etching methods. The experimental results indicate that the water contact angle for the perfluorodecyltrichlorosilane (PFTS) treatment polyimide (PI) film is 112.0${}^{\circ }$, which is larger than the pure PI film $(69.0^{\circ })$. The rap oil contact angle is 84.2${}^{\circ }$, which is also much larger than the contact angle of PI film $(12.0^{\circ })$. Moreover, the surface roughness of the prepared films was measured by white light interferometry (WLI). The surface roughness (Ra) of pure PI is 9.79nm, but with the application of FSiO₂ particles, the Ra of the films increases to 65.05nm. After plasma treatment, the Ra of the PI/FSiO₂ composite film increases to 186.71nm because plasma treatment can scratch the film surface and increase its roughness. However, treating the PI/FSiO₂ composite film with the plasma and PFTS, the Ra is only 88.90nm. This decrease in Ra is due to the PFTS, which is able to reduce the surface roughness. The development of composite films, compared to pure PI films, could prove to be an extremely valuable material in ICF experiments.

The poor interface compatibility between inorganic fillers and organic polymer matrix in nanocomposite has presented considerable challenges, which limit the applicable electric field ranges and reduce the interface polarization interaction. In this paper, Pb${}_{0.8}$Ba${}_{0.2}$ZrO₃ (PBZ) nanofibers were introduced into the polyvinylidene fluoride (PVDF) matrix to prepare composite film, and the effect of hot pressing on interface compatibility was investigated at volume composite ratios of 3% and 4%. For the untreated film, $P_s$ and $E_{+}$ of the 3 vol.% composite film are 9.68 $\mu$C/cm² and 401 MV/m, respectively, and those for the 4 vol.% composite film are 9.15 $\mu$C/cm² and 408 MV/m, respectively. These differences are mainly due to the impact of internal defects. After hot pressing, $P_s$ and $E_{+}$ for the 3 vol.% composite film became 10.22 $\mu$C/cm² and 490 MV/m, respectively. Those for the 4 vol.% composite film are 9.85 $\mu$C/cm² and 485 MV/m. Experiment and simulation results showed the beneficial effect of hot pressing, which ameliorated poor interfacial compatibility, reduced internal defects, and improved the crystallinity of the composite film. A high electrocaloric effect (ECE) was obtained by using the direct measure method. At −30${}^{\circ }$C, the $\mathrm{\Delta }T$ values of hot-pressed PBZ/PVDF film at 3$\surd$ and 4$\surd$ vol.% were 23.81 and 19.73 K, respectively. When temperature increased to 70${}^{\circ }$C, the $\mathrm{\Delta }T$ values were 9.44 and 7.01 K, respectively, which were 1.58 times of the values of a non-hot-pressed film. These results indicated that hot pressing alleviated the interface problem and resulted in high EC performance under a high-strength electric field.

A study of dielectric properties of composite films on the base of poly(vinylidene fluoride-trifluoroethylene) copolymer P(VDF-TrFE) and ferroelectric ceramics of barium lead zirconate titanate (BPZT) solid solution is presented in this work. The composite films containing up to 50 vol.% of BPZT grains with size $\sim$1$\mu$m were prepared by the solvent cast method. Frequency dependences of real and imaginary components of the complex permittivity were determined. The concentration dependence of the dielectric constant was discussed.

In this work, the study of dielectric properties of composite structures on the base of poly(vinylidene fluoride-triflouroethylene) copolymer P(VDF-TrFE) and porous aluminum oxide layers produced by the melt-impregnation is presented. Frequency dependences of dielectric characteristics of the composite samples were determined. The dielectric dispersion and ferroelectric switching processes in the composite structures were discussed.

The sol-gel method has been employed in the fabrication of mesoporous composite films consisting of a nonionic surfactant, Pluronic P123, as the organic component, and silica as the inorganic component. The hybrid nature of these films resulted in their having an internal structure consisting of nanometer size self-assembled organic mesostructures surrounded by a silica framework. These films served as the host matrix for the laser dye coumarin 481 (C481) and an energy transfer complex formed between C481 and J-aggregated meso-tetra(4-sulfonatophenyl)porphyrin (TSPP). Upon exposure to methanol vapor, a rapid and reversible decrease in fluorescence intensity occurs for films containing C481 alone as well as containing both C481 and TSPP. Steady-state and time-resolved spectroscopic studies suggest that the decrease in fluorescence intensity is primarily due to an excited state interaction between methanol and C481; while, additionally, morphological changes within the film appear to play a role for films containing both C481 and TSPP.