Morphology Of Composite Films Research Articles

A series of formic acid MOFs/polylactic acid blending composites with the improved dielectric performance in Co(II) systems

In order to improve the limited compatibility of existing polymer/ceramic dielectric composites and further enhance the energy storage density, MOF/polymer composite dielectrics have been explored, which exhibit good compatibility to the polymer matrix from abundant organic groups of the inorganic–organic hybrid metal-organic framework (MOF) fillers. However, they still lack a clear composition–structure–property rule, and the precise design of MOF fillers and polymer matrix becomes a prominent problem in these composites due to the diversity of the metal ions and the organic groups. Thus, in this paper, we present a series of formic acid MOFs/polylactic acid dielectric composites in which ferroelectric formic acid MOFs, namely PDLLA/[NH[Formula: see text](CH[Formula: see text])[Formula: see text]NH[Formula: see text]][M[Formula: see text](HCOO)[Formula: see text]][Formula: see text] and PDLLA/[CH[Formula: see text]NH[Formula: see text]][M[Formula: see text](HCOO)[Formula: see text]][Formula: see text], in which the formic acid MOFs are with different structures and different metal ions as fillers, including [NH3(CH[Formula: see text]NH3][MII(HCOO)3]2 (namely MOF–Co (M [Formula: see text] Co), MOF–Mg(M [Formula: see text] Mg), MOF–Mn (M [Formula: see text] Mn), with 1, 4-butanediamine ion as guest) and [CH3NH3][M[Formula: see text](HCOO)3]2 (namely MOF–Co[Formula: see text] (M = Co), MOF–Ni[Formula: see text] (Ni), with methylamine ion as guest). The composition and morphology of composite films were characterized by XRD, IR, SEM, DSC and UV, respectively, while the dielectric characterizations of the composites including the dielectric permittivity, the dielectric loss, the breakdown field strength and the energy density were also performed. The composition–structure–property relationships were also investigated including the influence of MOF content and MOF category. With the introduction of MOFs, the dielectric constant of the polylactic acid substrate was improved slightly while the breakdown field strength can be improved in some systems. Interestingly, the Co(II)-containing formic acid MOF has advantages over other formic acid MOFs with similar structure for the enhancement of the dielectric constant and breakdown field strength. Also, in some composite films with methylamine ion guest MOF fillers and low-MOF content (MOF–Co[Formula: see text] (1 vol.%) and MOF–Ni[Formula: see text] (1 vol.%)), the breakdown electric field enhanced significantly and further led to improved energy storage density which was about 43% higher than that of the polylactic acid matrix. The possible reason is that in these composites, the orientation of C–H bonds of MOFs seems more beneficial to the formation of hydrogen bonds between the carboxyl group of formic acid and the polylactic acid matrix. These relationships obtained from formic acid MOFs/polylactic acid composites are valuable to the design of high-performance polymer/MOF energy storage composites and may be a new perspective to the practical use of ferroelectric MOFs.

Preparation and characterization of citric acid crosslinked chitosan‐cellulose nanofibrils composite films for packaging applications

AbstractThe inferior water vapor permeability and water resistance properties are the major challenges that hindered the development of chitosan‐CNF composites for packaging applications. In this study, the chitosan‐CNF composite films were prepared with in situ crosslinking of citric acid (CA) to reduce the percent water uptake (WU) and water vapor permeability (WVP). The composite films were produced by the solvent casting method with 10%, 15%, and 20% CNF as a reinforcement, 20%, 25%, and 30% CA as a crosslinker, and 20% glycerol as a plasticizer. The Fourier transform infrared (FTIR) spectra of composite films with a peak at 1710 cm−1 confirmed the effective crosslinking of citric acid on the chitosan‐CNF matrix. The crosslinked composite films exhibited the lowest WU of 39% and WVP of 9.99 × 10−7 g/Pa s m2 with reduced light transmittance due to CNF reinforcement. The scanning electron microscopy (SEM) study showed the smooth surface morphology of composite films. The CA crosslinking slightly decreased the tensile strength of composite films. However, the composite film with optimal CNF and CA concentration (25% and 20%, respectively) exhibited comparable tensile strength with other synthetic and biopolymer composites and can be used as a potential biopolymer composite for packaging applications.

A molecular design approach towards elastic and multifunctional polymer electronics

Next-generation wearable electronics require enhanced mechanical robustness and device complexity. Besides previously reported softness and stretchability, desired merits for practical use include elasticity, solvent resistance, facile patternability and high charge carrier mobility. Here, we show a molecular design concept that simultaneously achieves all these targeted properties in both polymeric semiconductors and dielectrics, without compromising electrical performance. This is enabled by covalently-embedded in-situ rubber matrix (iRUM) formation through good mixing of iRUM precursors with polymer electronic materials, and finely-controlled composite film morphology built on azide crosslinking chemistry which leverages different reactivities with C–H and C=C bonds. The high covalent crosslinking density results in both superior elasticity and solvent resistance. When applied in stretchable transistors, the iRUM-semiconductor film retained its mobility after stretching to 100% strain, and exhibited record-high mobility retention of 1 cm2 V−1 s−1 after 1000 stretching-releasing cycles at 50% strain. The cycling life was stably extended to 5000 cycles, five times longer than all reported semiconductors. Furthermore, we fabricated elastic transistors via consecutively photo-patterning of the dielectric and semiconducting layers, demonstrating the potential of solution-processed multilayer device manufacturing. The iRUM represents a molecule-level design approach towards robust skin-inspired electronics.

Preparation and Characterization of Eco-Friendly Spent Coffee/ENR50 Biocomposite in Comparison to Carbon Black.

This study investigates the impact of spent coffee biochar (Biochar) compared to carbon black (CB) as a partial replacement for carbon black in epoxidized natural rubber (ENR). Particle size and elemental analysis were used to characterize the biochar and CB. Cure characteristics, tensile, thermal, and morphological properties on the effect of biochar and CB as filler were studied. It was found that incorporating 10 phr of spent coffee biochar could improve the composites’ tensile properties and thermal performance compared to carbon black. However, the addition of biochar significantly affects the maximum torque compared to CB and delays the vulcanization time. SEM study shows that biochar has a strong effect on the morphology of composite films. The FTIR graph reveals no substantial difference between compounds with biochar and CB. According to the thermal calorimetric study, the thermal stability of ENR-Biochar is higher than that of ENR-CB. Additionally, these findings suggest that the utilization of spent coffee as a sustainable biochar could be further explored, but little has been done in epoxidized natural rubber (ENR).

Morphology, Conductivity, and Mechanical Properties of Electropolymerized Polypyrrole/Silver-Coated Granular Microsphere Composite Films

We report a facile synthesis of polypyrrole/silver-coated granular microsphere composite films through electropolymerization process in the presence of low- and high-density conductive granular microspheres. The resulting morphologies of composite films were implicitly influenced by the density of microspheres as revealed by scanning electron microscopy (SEM). Energy-dispersive X-ray (EDX) analysis confirmed the existence of elemental composition of the polypyrrole and conductive microspheres, while Fourier transform infrared (FTIR) spectroscopy verified the presence of molecular bonding associated with the dopant anion in all the synthesized films. Resistivity measurements demonstrated enhanced nonlinear conductivity and a strong dependence of current density in composite films with increasing application of electric field. Improvement in nonlinear conductivities is linked to the formation of more effective conductive pathways that boosted intermolecular and inter-particle charge carrier migration. Tensile tests reveal that the conductive granular microspheres have the general tendency to decrease internal forces in composite films.

Updating the Role of Reduced Graphene Oxide Ink on Field Emission Devices in Synergy with Charge Transfer Materials.

Hydroiodic acid (HI)-treated reduced graphene oxide (rGO) ink/conductive polymeric composites are considered as promising cold cathodes in terms of high geometrical aspect ratio and low field emission (FE) threshold devices. In this study, four simple, cost-effective, solution-processed approaches for rGO-based field effect emitters were developed, optimized, and compared; rGO layers were coated on (a) n+ doped Si substrate, (b) n+-Si/P3HT:rGO, (c) n+-Si/PCDTBT:rGO, and (d) n+-Si/PCDTBT:PC71BM:rGO composites, respectively. The fabricated emitters were optimized by tailoring the concentration ratios of their preparation and field emission characteristics. In a critical composite ratio, FE performance was remarkably improved compared to the pristine Si, as well as n+-Si/rGO field emitter. In this context, the impact of various materials, such as polymers, fullerene derivatives, as well as different solvents on rGO function reinforcement and consequently on FE performance upon rGO-based composites preparation was investigated. The field emitter consisted of n+-Si/PCDTBT:PC71BM(80%):rGO(20%)/rGO displayed a field enhancement factor of ~2850, with remarkable stability over 20 h and low turn-on field in 0.6 V/μm. High-efficiency graphene-based FE devices realization paves the way towards low-cost, large-scale electron sources development. Finally, the contribution of this hierarchical, composite film morphology was evaluated and discussed.

Solvent Vapour Induced Film Formation of PS/AgNPs Composites Using Spectroscopic Techniques

In this work, pyrene labeled polystyrene (PS) latex dispersions and silver nanoparticles (AgNPs) were mixed at different weight ratios of AgNPS in the range of 0-50 wt%. Powder (PS/AgNPs) films were prepared on glass substrates from these mixtures by the drop-casting method at room temperature. The fast transient fluorescence (FTRF) technique was used to monitor the film formation process of PS/AgNPs composites by measuring the fluorescence lifetimes of pyrene during vapour exposure. It was observed that pyrene lifetimes decreased as vapour exposure time, t increased obeying Stern–Volmer kinetic. The optical transmission (UVV) experiments showed that the transparency of the films decreased with increasing AgNPs content. Transparent films were produced for the composites with 0 to 20 wt % of AgNPs content. The Prager–Tirrel model was employed to FTRF and UVV data to obtain back-and-forth frequencies, ν, of the reptating PS chains during vapour induced film formation process and polymer interdiffusion was found to obey a t1/2 law. Although the conductivity increased by 3 orders of magnitude with increasing AgNPs content, the composites behaved like an insulator. The morphology of composite films also progressively changed during vapour exposure and affected by AgNPs content.

Preparation, physicochemical properties and biocompatibility of biodegradable poly(ether-ester-urethane) and chitosan oligosaccharide composites

In the paper, novel composites of biodegradable poly(ether-ester-urethane) (PEEU) and water-soluble chitosan oligosaccharide (CHO) were prepared using a simple physical mixing method and their potential application as biomaterials was assessed. The PEEU and CHO were dissolved in N,N-dimethylformamide to get a homogenous solution, then the composite films were obtained by the solvent evaporation method. The composites were characterized by FT-IR, and the influence of CHO content on the physicochemical properties of the composite films, including thermal properties, surface morphologies, mechanical properties, surface and bulk hydrophilicity, and in vitro biodegradability, were researched. The thermal stability studies indicated that the composite films had lower initial decomposition temperature and higher maximum decomposition temperature than PEEU film. Only one broad endothermic peak found in DSC curves demonstrated the high compatibility of CHO with PEEU. The ultimate stress and elongation at break of composite films decreased with the increment of CHO content, and the CHO content in the composites should be controlled no more than 25 wt% in order to maintain the mechanical properties (ultimate stress: 18.5 MPa; elongation at break: 890%) to meet the requirement of implant materials. The surface morphologies of composite films were observed by cold field emission scanning electron microscope (FE-SEM), and the results indicated that the homogeneous-dispersed composites could be obtained with CHO content being less than 20 wt%. The results of water contact angle and water absorption showed that the surface and bulk hydrophilicity were closely related with the water-solubility of CHO component. In vitro degradation studies showed that the degradation rate increased with the increasing content of CHO in composites, indicating that the degradation rate of composite films could be controlled by adjusting CHO content. The surface blood compatibility of the composite films was examined by bovine serum albumin adsorption and platelet adhesion tests. It was found that composite films had improved resistance to protein adsorption and possessed excellent resistance to platelet adhesion.

Fast switching electrochromic nanocomposite based on Poly(pyridinium salt) and multiwalled carbon nanotubes

This paper represents a simple approach to modulate electrochromic properties of poly (4,4′-(1,4-phenylene)bis (2,6-diphenylpyridinium) triflate) (PV) by the formation of composite material with multiwalled carbon nanotubes. The polymer acts as a functionalizing agent for MWCNTs to prevent their agglomeration enabling the formation of stable dispersions. They were further used to prepare uniform electrochromic films by spin-coating method. The films were characterized by electrochemical and spectroelectrochemical methods. To evaluate the influence of MWCNTs on the electrochromic properties of PV the dispersions with various PV/MWCNTs compositions were studied. Upon the addition of MWCNTs the absorption bands and redox peak potentials of polymer did not change. However, the decrease of the peak separation between reductive and oxidative waves and the significant improvement of switching times (one of the most important properties of electrochromic materials) were demonstrated. At the practically identical optical contrast both coloration and bleaching times decreased that can be explained by the composite film morphology. This effect became significant for high PV concentrations in the initial solution. The decrease of coloration and bleaching times reached 30% and 50%, respectively. The resulting composite material exhibited fast (200–400 ms) response times and could be used as a promising candidate for novel electrochromic devices.

Thin-film photovoltaic devices incorporating low-bandgap push-pull molecules dispersed in passive polymeric matrices

Active layers in many thin-film organic photovoltaic devices (OPVs) contain light-absorbing polymers that serve as electron donors, mixed with appropriate electron acceptors. In principle, the polymers can be replaced by small molecules with suitable bandgaps, which offer multiple advantages, including well-defined structures and methods of synthesis and purification that provide uniform samples. However, such materials often undergo separation of phases and crystallization, so making long-lived films that remain smooth, homogeneous, flexible, and transparent is not easy. We have found that effective OPVs can be made by dispersing mixtures of low-bandgap push–pull small molecules as electron donors and [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) as electron acceptor in matrices of optoelectronically passive conventional polymers, including polystyrene, poly(methyl methacrylate), poly(vinyl chloride), poly(ethylene glycol), and poly(dimethylsiloxane). By varying the identity of the matrix, its molecular weight, the loading of active components, and the conditions of annealing, we have produced efficient OPVs from components that would otherwise have undergone phase separation and crystallization, leading to poor performance. Layers with up to 35% matrix were found to be effective and could be fabricated at room temperature by simple processes. To probe the role of the polymers as dispersants, morphologies of composite films were examined by atomic force microscopy and electron microscopy. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017

Flexo-green Polypyrrole – Silver nanocomposite films for thermoelectric power generation

Conducting polymers offer various advantages over inorganic thermoelectric materials such as eco-friendliness, a reduced manufacturing cost, flexibility, low thermal conductivity and amenability to tuning of electrical properties through doping; have recently drawn much attention for conversion of low temperature waste heat (≤150°C) into electricity. In this study, we investigated the thermoelectric properties of hybrid films of polypyrrole and silver (PPy-Ag). These films were prepared on biaxially oriented polyethylene terephthalate (BOPET) flexible substrates by eco-friendly one pot photo-polymerization method using aqueous solution of silver nitrate (AgNO3) as photo initiator. Detailed characterization of the samples revealed that morphology of composite films reorganized with the change in AgNO3 concentration during synthesis. Increasing AgNO3 concentrations resulted in PPy films containing Ag nanoparticles, nanoclusters as well as macroclusters. With alteration in concentration and size of Ag particles in PPy matrix, it has been observed that the electrical conductivity of the films increased (1.5–17.3Scm−1), thermal conductivity decreased (0.16–0.002Wm−1K−1), while Seebeck coefficient moderately reduced from 10.9μV/K to 5.8μV/K. Nearly same doping (N+/N∼0.35) content, improved conjugation length and incorporation of Ag between the PPy chains resulted in improved charge carrier mobility/electrical conductivity in the PPy–Ag films. It is proposed that the interface of Ag and PPy served as scattering sites for phonons, thus leading to reduction of thermal conductivity. This synergetic combination of high electrical conductivity, extremely low thermal conductivity along with moderate Seebeck coefficient in the PPy-Ag films resulted in the highest figure-of-merit of ∼7.4×10−3 at 335K among reported PPy based materials. A prototype thermoelectric power generator was fabricated by integrating six numbers of PPy-Ag films. The fabricated device exhibited maximum voltage and power respectively as 6mV and ∼30pW. The present work opens new avenues for the thermoelectric applications of rarely explored flexible PPy-Ag films prepared by a simple nature-friendly photo-chemical process at room temperature.

Solution processable sol–gel derived titania gate dielectric for organic field effect transistors

A gate dielectric has key role in thin film transistors. Insulating polymers incorporated with oxide nanoparticles are the ideal candidates for the gate dielectrics due to their solution processability and relatively high dielectric constant. The polyvinyl alcohol cross linked with ammonium dichromate was spun onto fluorine doped tin oxide (FTO) substrates. Titania particles were incorporated into a mixture of ammonium dichromate and polyvinyl alcohol (PVAad) solution and the resultant films were irradiated by ultraviolet irradiation. TiO2 particles were prepared using acetic acid as a surfactant by sol–gel method. Metal–insulator–semiconductor (FTO/(PVAad + TiO2)/Au) structure was fabricated by evaporating Au electrode. The electrical properties of polymer composites layer have been studied with the effect of binding agent, concentration of TiO2 nanoparticles, and the irradiation of UV light. Capacitance–voltage, capacitance–frequency, and current–voltage measurements were performed using two probes measurement setup. The obtained electrical results illustrated that the dielectric constant of prepared films was increased from approximately 2 for PVAad to 7 for PVAad +TiO2 films. These results further corroborated that the capacitance is independent of frequency and the leakage current was less than 2 × 10−12 A. This leakage current is small enough and hence PVAad + TiO2 is an ideal gate dielectric for the fabrication of field effect transistors. The surface morphology of composite films has been studied by means of field emission scanning electron microscopy. The micrograph images illustrated huge variation in the morphologies of the hybrid films after incorporation titania particles into polymer matrix and UV irradiation.

Thermal and Mechanical Properties of PLA/BN/BR Ternary Composite Films

In this research, the effects of boron nitride (BN) and polybutadiene (BR) on thermal and mechanical properties of polylactic acid (PLA) composite films were studied. PLA thin film in the thickness of less than 0.2 mm was fabricated using the solvent casting method. The loadings of BN and BR of 0-7 wt% were applied to the PLA matrix. The morphologies of composite films were characterized by scanning electron microscopy (SEM). The thermal and mechanical properties were also investigated. It was found that the addition of BN and BR can improve the thermal properties of PLA composite films. PLA/BN3%/BR5% ternary composite films provided the higher thermal properties, tensile strength and Young’s modulus, compared to PLA/BN1%/BR5% ternary composite films.

Morphological, structural, functional effect and Comparative study of PPy with PPy/TiO2, and PPy/ZnO composite films by Nebulizer Spray coating Technique

Soluble polypyrrole, PPy/TiO2, and PPy/ZnO composite has been synthesized by chemical method in aqueous solution of pyrrole monomer. The prepared composite sample was dissolved in m-cresol solvent. The solution was coated on glass substrate by NSP technique at 150°C for 5 minutes. The sprayed films are characterized by SEM, EDAX, XRD, and FT-IR. SEM graph reveals globular morphology and the presence of functional acid on PPy film surface. SEM study shows that oxide nanoparticles have a strong effect on the morphology of composite films. The presence of elemental constituents is confirmed of Ti. Zn, and O from energy dispersive X-ray analysis. XRD study reveals TiO2 peaks represent the tetragonal specimen lines and ZnO peaks represent the hexagonal structure. The presence of functional groups of organic and inorganic compounds is indicated in FT-IR studies. The investigation of nanocomposites confirmed their morphological effect, hybrid composite, and suitability for optoelectronics devices © 2015 Ishitv Technologies LLP All rights reserved.

Controlled incorporation behavior of gold nanoparticles into ABC triblock terpolymer with double-helical morphology

We demonstrated the controlled incorporation of Au nanoparticle grafted with polystyrene (PS) molecules in the helical microdomains of ABC-type linear triblock terpolymers composed of PS, polyisoprene (PI) and poly(methyl methacrylate) (PMMA). The Au nanoparticles grafted with three PSs with different molecular weights were synthesized and incorporated into the terpolymer films. The morphologies of composite films and localization of Au nanoparticles were three-dimensionally characterized with transmission electron microtomography observation. By varying the molecular weights of grafted PS molecules on Au nanoparticles, their assemblies were successfully controlled in the double-helical microdomains.

Spray Deposition of Titania Films with Incorporated Crystalline Nanoparticles for All‐Solid‐State Dye‐Sensitized Solar Cells Using P3HT

Spray coating, a simple and low‐cost technique for large‐scale film deposition, is employed to fabricate mesoporous titania films, which are electron‐transporting layers in all‐solid‐state dye‐sensitized solar cells (DSSCs). To optimize solar cell performance, presynthesized crystalline titania nanoparticles are introduced into the mesoporous titania films. The composite film morphology is examined with scanning electron microscopy, grazing incidence small‐angle X‐ray scattering, and nitrogen adsorption–desorption isotherms. The crystal phase and crystallite sizes are verified by X‐ray diffraction measurements. The photovoltaic performance of all‐solid‐state DSSCs is investigated. The findings reveal that an optimal active layer of the all‐solid‐state DSSC is obtained by including 50 wt% titania nanoparticles, showing a foam‐like morphology with an average pore size of 20 nm, featuring an anatase phase, and presenting a surface area of 225.2 m2 g−1. The optimized morphology obtained by adding 50 wt% presynthesized crystalline titania nanoparticles yields, correspondingly, the best solar cell efficiency of 2.7 ± 0.1%.

The Electrochemical Behaviour of PEDOT Film Electrosynthesized in Presence of Some Dopants

Electropolymerization and characterization of poly(3,4-ethylene dioxythiophene) (PEDOT) doped with functionalized single-walled carbon nanotubes (SWANTs) polyaminobenzene sulfonic acid (PABS) and different dopants were studied. It was fabricated by a simple oxidative electropolymerization method. The nanocomposite coatings have been prepared by using electrochemical methods from aqueous solutions, such that the components were deposited onto platinum electrode substrate. The morphology of composite films was analyzed by scanning electron microscopy (SEM). The electrochemical and physical properties of the resulting composites were evaluated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and Fourier transform infrared spectroscopy (FT-IR) techniques in 0.1 M LiClO4 aqueous solutions. The value of specific electrochemical capacitance of the composite films is considerably higher than that of the pure polymers films. The improved properties of the electrodes were obtained by using these composite films. The dopant substances used were sodium dodecyl sulfate (SDS) and 1,2-Dihydroxy- benzene-3,5-disulfonic acid disodium salt hydrate (tiron).

Morphological control and switchable photoluminescence responses of silica nanoparticles-modified polymer-dispersed liquid crystal composite films

An electro-optic tunable device is fabricated by the incorporation of silica nanoparticles as a dopant into polymer-dispersed liquid crystal composite film followed by UV curing through polymerisation-induced phase separation process. These silica-modified fibrous aggregates of polydimethylsiloxane provide stability to the nematic liquid crystal molecules. The interaction between dispersed silica nanoparticles and modified polymer network improves the polymer/liquid crystal interface, which was successfully analysed through scanning electron microscopy. It also controlled the birefringence in nematic liquid crystal droplets and provided optical stability to the off-state (opaque) scattering of an electro-optic device. The electrical tuning of photoluminescence intensity during the stage triggering from ‘Switch OFF state’ to ‘Switch ON state’ shows dependence on the morphology of composite films. It can find out potential applications in electrically switchable shutters in display market.

Hybrid silica luminescent materials based on lanthanide-containing lyotropic liquid crystal with polarized emission

This paper represents the template method for synthesis of hybrid silica films based on Ln-containing lyotropic liquid crystal and characterized by efficient luminescence. Luminescence films were prepared in situ by the sol–gel processes. Lyotropic liquid crystal (LLC) mesophases C12H25O(CH2CH2O)10H/Ln(NO3)3·6H2O/H2O containing Ln (III) ions (Dy, Tb, Eu) were used as template. Polarized optical microscopy, X-ray powder diffraction, and FT-IR-spectroscopy were used for characterization of liquid crystal mesophases and hybrid films. The morphology of composite films was studied by the atomic force microscopy method (AFM). The optical properties of the resulting materials were evaluated. It was found that hybrid silica films demonstrate significant increase of their lifetime in comparison with an LLC system. New effects of linearly polarized emission revealed for Ln-containing hybrid silica films. Polarization in lanthanide-containing hybrid composites indicates that silica precursor causes orientation of emitting ions.

The Investigation of Reduced Graphene Oxide/P3HT Composite Films for Ammonia Detection

In this paper, single reduced graphene oxide (rGO) and rGO/Poly (3-hexylthiophene) (P3HT) composite films were prepared by the spray process, which were deposited on the interdigitated transducers for preparing the resistive ammonia (NH3) sensor. The morphology of sensitive films was characterized by scanning electron microscopy (SEM). The gas-sensing properties of GO/P3HT film sensor were tested and analyzed. The results showed that rGO/P3HT composite film sensor exhibited better sensing properties and restorability than that rGO film sensor, which maybe was ascribed to π-π interaction between rGO and P3HT and the superior surface morphology of composite films.