Poly O-methoxyaniline Research Articles

In-situ deposition of POMA/ZnO nanorods array film by vapor phase polymerization for detection of trace ammonia in human exhaled breath at room temperature

The o-methoxyaniline (OMA) monomer was polymerized in-situ by vapor phase polymerization to form uniform and dense poly-o-methoxyaniline (POMA) film on the surface of ZnO nanorods array film which was pre-prepared by hydrothermal method. The as-prepared POMA/ZnO composite shows the best response at 40 min of vapor phase polymerization time. The response to 100 ppm ammonia at 25 °C is 8.88. The recovery time of 136 s has a certain advantage in the reported room temperature ammonia sensors. The lowest detectable concentration is as low as 0.01 ppm. The fast recovery time and low detection limit make the sensor have broad application prospects. In order to explore the response mechanism of POMA/ZnO composite to ammonia gas, the work function of POMA and ZnO and corresponding band gap energies were tested respectively. And the effect of the formation of p-n heterostructure on gas response was further explored. The actual application test results reflect that the sensor can effectively identify NH3 in the mixed gas during the production, storage and transportation of NH3. This can provide real-time early warning of NH3 leakage. Especially, the sensor can detect trace amount of NH3 in the human body's exhaled breath which is expected to realize the preliminary screening of patients with kidney disease through the detection of exhaled breath in the medical field.

Synthesis of ZnO@poly-o-methoxyaniline nanosheet composite for enhanced NH3-sensing performance at room temperature

Poly-o-methoxyaniline (POMA) and zinc oxide (ZnO) composites were prepared via in situ polymerization and characterized by thermogravimetry thermal analysis, X-ray diffraction analysis, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and N2 sorption measurement. The composites show different morphology when the ratio of POMA and ZnO varies. At a ratio of2:2, the composite shows thinner nanosheet structure with smooth surface and exhibits best response to NH3 at room temperature. TheZnO@POMA nanosheet sensor shows good selectivity and a wideresponse range (linear ranges from 0.05-1 pmm and 10-100 ppm of NH3). The lowest detection limit reaches 0.05ppm. The sensor exhibits good reversibility. Based on the testing results of ultraviolet diffuse reflection spectroscopy and Kelvin probe technique, the adsorption and desorption of NH3 molecules on the sensing material and the formation of p-n heterostructure between ZnO and POMA and their synergistic effects are further explained. More importantly, the sensor possessed excellent moisture resistance. The overall test results of ZnO@POMA show that the sensor has good practical applicability for detecting trace NH3 at room temperature. Graphical abstract.

Electrical Characterization of V2O5/POMA Deposited by the Casting Technique

Conductive polymer derivatives, such as poly-o-methoxyaniline (POMA), have been broadly used in different applications because they present characteristics similar to those of polyaniline. POMA can intercalate into a V2O5 matrix to improve its structural and electrical properties, and thin films of V2O5/POMA can be deposited by different techniques to extend their technological applications after intercalation reactions. Then, V2O5/POMA hybrid material was deposited by casting technique and characterizated for, further, to be ued as component in amperometric ammonia gas sensor. Our results show the influence of the deposition technique on electrical properties. Indeed, the values of parameters such as resistance, interface effects and conductivity slightly change according to the deposition technique being used.

Cationic surfactant assisted synthesis of poly o-methoxy aniline (PoMA) hollow spheres and their self healing performance

Hollow microspheres of poly(o-methoxy aniline) (PoMA) were prepared in a solution of cetyltrimethylammonium bromide (CTAB) using ammonium persulfate (APS) as oxidant.

Conducting Polymers as Binder Additives for Cathodes in Li Ion Battery

Commercial applications of Li-ion batteries for the electro mobility and stationary storage require high energy density, high rate capability and long cycle life of the battery. In this paper we have shown the improvement in energy density and rate capability of LiFePO4 composite cathodes by partially replacing conventional binders with poly-o-methoxyaniline (POMA) and tosylate doped poly(3,4-ethylenedioxythiophene) (PEDOT:p-Tos). Due to different redox properties of the used conducting polymers, POMA specifically improves the capacity to 14% as compared to conventional polyvinylidene difluoride (PVDF) and in case of PEDOT:p-Tos 83% capacity is retained at 5 C charging rate.

Characterization of substituted polyaniline films using Raman spectroscopy: III. Study of a methoxylated polymer: POMA

The electropolymerization of o-anisidine leads to the formation of a polymer which is in the same time strongly oxidized and charged in a large potential range: the poly- o-methoxyaniline (POMA). The POMA Raman features are strongly different from the polyaniline (PANI) ones; in particular a new band, absent from the PANI spectrum, prevails in a large potential range. The nature of the polymer structures obtained in function of the polarization potential is discussed from their Raman spectra. A new polymeric configuration of the oxidized/charged rings is therefore described.

Electrochemical formation and copper modification of poly-o-methoxyaniline

The electrosynthesis of poly-o-methoxyaniline (POMA) is studied under potentiostatic, potentiodynamic and pulse potentiostatic conditions. The three types of POMA layers are compared with respect to their electrochemical behaviour, stability and surface morphology. Copper electrodeposition is comparatively studied in the three types of POMA at two different thicknesses. It is established that for thin (<1 μm) POMA coatings copper deposition occurs in one and the same way in all layers, defects (e.g. large pores) being most probably the promoters for metal crystallization. In contrast, thick POMA layers synthesized by the three electrochemical procedures show marked difference with respect to the amount and location of the deposited copper species.