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Effect of surface treatment on electrical properties of polydimethylsiloxane based triboelectric nanogenerator
(2020-01-01)
Panprom, Parinya
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Vittayakorn, Naratip
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Nawanil, Chanisa
This research investigated the effect of surface treatment on electrical properties of flexible triboelectric nanogenerator (TENG). Polydimethylsiloxane (PDMS) was used as triboelectric layer. The PDMS pads were prepared by simple casting method and the effect of surface treatments by heat and acid was examined. Physical morphology of treated samples were investigated by scanning electron microscope (SEM). Electrical properties were measured under continuous periodic knocking. The results revealed that the heat-treated PDMS-based TENG showed the outstanding output voltage. The maximum output voltage of heat-treated based TENG reached approximately 9 V, which was over 4 times larger than those of normal PDMS based TENG. The research demonstrated the feasibility to utilize PDMS-based TENG as an energy harvesting device and presented a cost-effective method for producing high-efficiency PDMS based TENG.
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Synthesis of BaTiO3@TiO2-sheet Core-Shell Structured Nanocomposites
(2019-01-02)
Nawanil, Chanisa
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Panprom, Parinya
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Makcharoen, Worawut
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Khaosa-Ard, Krittanat
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Maluangnont, Tosapol
Core-shell structure nanocomposites have been of interest, as they can exhibit unique properties arising from the combination of peculiar characteristics of each component. In this research, core-shell structured nanocomposites, comprising barium titanate (BaTiO<inf>3</inf>; BT) nanoparticles as the core and titanate (TiO<inf>2</inf>) nanosheets as the shell, were prepared. The surface of barium titanate (BT) nanoparticles was modified chemically by hydrogen peroxide (H<inf>2</inf>O<inf>2</inf>) to create hydroxyl groups. TiO<inf>2</inf> nanosheets were deposited on the surface of the functionalized BT core, via alternate adsorption with oppositely charged polyelectrolyte poly(diallyl dimethylammonium) (PDDA) cations to produce an ultrathin TiO<inf>2</inf> shell layer that encapsulates BaTiO<inf>3</inf> nanoparticles. The structure of the core-shell particles was investigated in order to illustrate their formation mechanisms. Furthermore, this work reported the advance in utilizing a core-shell nanostructure to enhance relative permittivity and maintaining a low loss of polymer nanocomposites. A significant improvement in relative permittivity is attributed to the TiO<inf>2</inf> shell, which acts as polarizable dipoles and consequently enhances interfacial polarization. The results indicated that the structure of core-shell nanocomposites is attractive as a novel structural building block for fabricating novel materials and electronic devices.
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Electrical and dielectric properties of barium titanate–polydimethylsiloxane nanocomposite with 0-3 connectivity modified with carbon nanotube (CNT)
(2019-01-02)
Nawanil, Chanisa
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Makcharoen, Worawut
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Khaosa-Ard, Krittanat
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Maluangnont, Tosapol
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Vittayakorn, Wanwilai
This study explored the preparation and electrical properties of 0–3 barium titanate/polydimethylsiloxane nanocomposites by dispersing barium titanate nanoparticles (BaTiO<inf>3</inf>; BT) into the polydimethylsiloxane (PDMS) matrix phase. The effect of barium titanate nanoparticles on electrical properties has been investigated systematically, and the relative permittivity of nanocomposites was found to increase significantly with increasing barium titanate content. Different theoretical models were used to predict the dielectric constant of these composites and compare their experimental value with the theoretical value in order to find an appropriate equation. The result indicated that the dielectric properties of composites are influenced not only by relative permittivity of the components but also dependence on interactions between ceramics and polymers. Furthermore, the preparation and dielectric properties of BT/PDMS nanocomposites modified with carbon nanotube (CNT) were also studied. The dielectric results demonstrate that adding CNT can enhance the relative permittivity of the BT/PDMS composite via improvement of dispersion and distribution of the BT nanoparticles in the PDMS matrix phase. Moreover, the electrical outputs from the BT/PDMS/CNT nanocomposites generator were measured under periodic knocking. The nanocomposites innovatively expand the feasibility of self-powered energy systems for smart sensor and energy harvesting applications.
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Tetragonal BaTiO3 nanowires: A template-free salt-flux-assisted synthesis and its piezoelectric response based on mechanical energy harvesting
(2019-01-01)
Charoonsuk, Thitirat
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Sriphan, Saichon
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Nawanil, Chanisa
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Chanlek, Narong
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Vittayakorn, Wanwilai
Intense research has been carried out towards the synthesis of one-dimensional (1D) barium titanate (BaTiO<inf>3</inf>: BT) because of its high output performance with anisotropic direction, which is expected to be applicable in piezoelectric nanogenerators for self-powered devices. This article emphasizes the essential process in producing BaTiO<inf>3</inf>: BT nanowires (NWs) in a simple and cost-effective way via a template-free salt-flux-assisted (SFA) method. The single phase of tetragonal BaTiO<inf>3</inf> was confirmed by X-ray diffraction (XRD) with Rietveld refinement analysis and Raman spectroscopy. The spontaneous polarization of 49.7 μC cm<sup>-2</sup> was calculated. Field-emission scanning electron microscope (FE-SEM) and transmission electron microscope (TEM) micrographs show uniform NWs with a diameter of ∼70 nm and a length of more than 2 μm. The corresponding selected-area electron diffraction (SAED) pattern displayed single-crystalline nature within tetragonal symmetry, and the lattice fringes demonstrate growth along the [111]-orientation of the 1D-BaTiO<inf>3</inf> nanowires (BT-NWs). Furthermore, this article exhibits progress made in applying energy harvesting nanocomposite materials. The flexible nanocomposite of BT-NWs in polydimethylsiloxane (PDMS) with the carbon nanotubes (CNTs) conductive filler was also prepared simply and cost-effectively. Its piezoelectric response of ∼44.18 V and ∼1.35 μA for the impulsive output voltage and current was investigated after the poling process. A high piezoelectric charge coefficient (d<inf>33</inf>) of ∼115 pC N<sup>-1</sup> for the poled BT-NWs/CNTs/PDMS device was achieved, which was more than 8 times higher than for the non-poled device. This research summarily represents the choice of a simple way to produce 1D nanomaterials and suggests the possible development of BT-NWs in the application of harvesting/detecting mechanical energy that drives low-powered electronic devices.
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Influence of dispersed phase morphology on electrical and fatigue properties of BaTiO3/PDMS nanogenerator
(2018-11-01)
Sriphan, Saichon
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Nawanil, Chanisa
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Vittayakorn, Naratip
A flexible piezoelectric nanogenerator (FPENG) was fabricated by incorporating barium titanate (BT) fibers and BT powders into polydimethylsiloxane (PDMS) matrix phase, also with an interdigital electrodes (IDEs). The electrospinning method was used to prepare BT fibers. Phase structure was carried out by the x-ray diffraction (XRD) technique. By using the Rietveld refinement method, a tetragonal structure of BT fiber could be confirmed. The scanning electron microscopy results showed a non-smooth surface of BT fibers, indicating the polymeric and organic precursors have been removed. The fabricated FPENG with 50% ratio of BT fibers was capable to generate an open-circuit voltage of ≈ 12 V and a short-circuit current of ≈ 1 μA. The effect of dispersed phases inside FPENG becomes the role to improve the output performance. This FPENG device can operate up to 5k times before degeneration. By continuously pressing up to 40k times, the output voltage tended to decrease reaching to a null value. The mechanical fatigue effect has been found that it related to the damage produced at the interface between IDEs and PDMS during pressing. The present results can be guided to further design the material and the device structure to obtain high-performance and stability of the FPENG devices.
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Characterization and dielectric properties of nanocomposite made of lead zirconate nanofibers and polyvinylidene fluoride improved with carbon nanotubes
(2013-12-01)
Nawanil, Chanisa
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Rerkratn, Apinai
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Seeharaj, Panpailin
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Vittayakorn, Naratip
A three-phase PZ/CNT/PVDF nanocomposite comprising lead zirconate (PZ) nanofibers, polyvinylidene fluoride (PVDF) and a small volume fraction of carbon nanotubes (CNT) was prepared by the solvent casting technique followed by composite heating at 80°C. The PZ/CNT/PVDF composites were characterized by X-ray diffraction, FT-IR and scanning electron microscopy (SEM). The dielectric properties of the composite were studied as a function of the frequency by an LCR meter. The dielectric constant of the PZ/CNT/PVDF nanocomposite was found to be in the range of 18-61 within the measurement frequencies from 100 Hz to 2 MHz. This value is higher than the dielectric constant of the PZ/PVDF nanocomposite. The measured dielectric properties demonstrate that the addition of CNT can improve the dielectric property appearance of the composite. © 2013 Copyright Taylor and Francis Group, LLC.
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Effect of chemical treatment on phase transition of lead zirconate nanofibers
(2013-12-01)
Nawanil, Chanisa
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Rerkratn, Apinai
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Seeharaj, Panpailin
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Vittayakorn, Naratip
Lead zirconate (PZ) nanofibers were treated by the solvothermal method in the presence of dimethyl formamide (DMF) solution in order to investigate the effect of chemical treatment on phase transition of PZ nanofibers. The influences of temperature and reaction time are described. The crystal structure, phase transition and morphology of the powders were analyzed by X-ray diffraction (XRD), fourier-transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). The results of DSC confirmed that chemical treatment with DMF could effect the AFE-PE phase transition of PZ nanofibers efficiently. Significant changes of fiber size and morphology after chemical treatment are shown by SEM images. Copyright © Taylor & Francis Group, LLC.
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The effect of thai glutinous rice starch on the synthesis of lead zirconate (PbZrO3) nanofibers via the electrospinning method
(2013-05-01)
Nawanil, Chanisa
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Vittayakorn, Wanwilai
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Muanghua, Rangson
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Niemcharoen, Surasak
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Prachayawarakorn, Jutarat
This study synthesized blended lead zirconate (PbZrO<inf>3</inf>;PZ)/ poly(ethylene oxide)(PEO)/Glutinous rice starch (GRS) nanofibers by the electrospinning method. A number of parameters such as the ratio between PEO and GRS and calcination temperature have been studied. The as-spun PZ/PEO/GRS composite and PZ fibers were characterized by TG-DTA, X-ray diffraction, FT-IR and SEM, respectively. SEM results showed that smooth and continuous fibers were obtained at the volume ratio of 10:2:1, PZ/PEO/GRS. After calcination of the as-spun PZ/PEO/GRS composite nanofibers at 650 °C for 4 h, PZ nanofibers with perovskite structure were obtained successfully. The fibers had a uniform and smooth surface without grain boundaries. However, when the calcination temperature increased to 750 °C and 850 °C, the fiber represented a necklace-like structure with grain boundaries arranged by grain to grain unit cell clusters. Copyright © 2013 American Scientific Publishers.
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Preparation and dielectric properties of 3-3 lead zirconate/polyvinylidene fluoride nanocomposite
(2013-01-01)
Nawanil, Chanisa
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Vittayakorn, Wanwilai
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Prachayawarakorn, Jutarat
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Vittayakorn, Naratip
Composites made of electroactive ceramics and a ferroelectric polymer are very attractive for applications since they exhibit good piezoelectric and pyroelectric properties, low densities and their properties can be tailored to various requirements. Here, we reported the preparation and dielectric properties of 3-3 PZ/PVDF nanocomposites by infusion of polyvinylidenedifluoride (PVDF) into the PZ nanofiber mat followed by heating of the composite at 80°C. The 3-3 PZ/PVDF composites were characterized by X-ray diffraction, FT-IR, SEM and LCR meter. The dielectric constant of the PZ/PVDF nanocomposite are relatively stable in the range of 21.98-18.21 within the measurement frequencies from 100 Hz to 2 MHz. This value is higher than the dielectric constant of the polyvinylidene fluoride. Moreover, the dielectric loss of the composite is below 0.09 at low frequencies. © 2013 Copyright Taylor and Francis Group, LLC.
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Synthesis and phase evolution of electrospun antiferroelectric lead zirconate (PbZrO3) nanofibers
(2012-08-01)
Nawanil, Chanisa
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Boomchom, Banjong
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Prachayawarakorn, Jutarat
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Vittayakorn, Wanwilai C.
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Vittayakorn, Naratip
Lead zirconate (PbZrO<inf>3</inf>; PZO) fibers were synthesized by the electrospinning method using a solution that contained 5 wt% poly(ethylene oxide) (PEO) in ethanol and a sol-gel solution of PZO. Some parameters varied, for example, the ratio between PEO and PZO, concentrations of the precursor solution, flow rate, and calcination temperature. The as-spun and calcined PZO/PEO composite fibers were characterized by TG-DTA, X-ray diffraction, FT-IR, SEM and TEM. PZO fibers were obtained successfully with a well-developed perovskite structure after as-spun PZO/PEO composite fibers were calcined using the PZO/PEO volume ratio of 10:3 at a PZO concentration of 1.0 M at 650 °C for 4 h. Stable nanofibers were produced with an average diameter of 300 ± 64 nm. Additionally, the PZO fibers showed a Curie temperature that rose by nearly 13 °C, when comparing with a normal PZO particle. © 2012 Elsevier B.V. All rights reserved.

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