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Development of a Small Ultrasonic Cleaning Bath based on Harmonic Response Analysis
(2024-01-01)
Worradechaudom, Warakorn
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Chaiaiad, Chatchapat
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Thongsri, Jatuporn
This article reports the development of a 0.27 L small ultrasonic cleaning bath (SUCB) with a 45 kHz single transducer to enhance cleaning efficacy based on harmonic response analysis (HRA). First, the HRA results revealed the uneven acoustic pressure inside the SUCB emerged from the transducer, depending on the applied voltage. As expected, the higher the applied voltage, the greater the acoustic pressure, and away from the transducer, the acoustic pressure decreased, consistent with the foil corrosion test, confirming the research methodology's credibility. Then, the transducer has been redesigned to develop the SUCB. Last, using the HRA, the simulation results indicated that the redesigned transduce, adding front and back masses like a horn shape, enhanced the acoustic pressure and helped to increase cleaning efficacy compared to the conventional SUCB. The findings were applied to develop a new generation of the SUCB. This article presents a step-by-step HRA technique that can be practically used in manufacturing design.
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Conversion of Mechanical Energy to Electrical Energy Using Piezoelectric Materials for Bicycle Lane Lighting Systems
(2022-07-01)
Jettanasen, Chaiyan
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Songsukthawan, Panapong
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Ngaopitakkul, Atthapol
This study examined the electromechanical characteristics of piezoelectric materials, which constitute a compact renewable energy source; these materials can convert mechanical energy (such as pressure or a cumulative impact) in the form of mechanical stress to electricity. This study further explored systems that require moderate energy and utilize piezoelectric materials to create an energy-generating floor. The electrical characteristics of these piezoelectric materials were studied, including the feasibility of installing them as a power source for road lighting, particularly cycling lanes. Furthermore, the effects of riders’ weights and cycling speeds were investigated. The results indicate that the electric power generated is adequate for the installation of these materials and can thus help improve visibility in the event of insufficient lighting.
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Piezoelectric enhanced photocatalytic properties of PVDF–ZnO/Cu nanofibers prepared by electrospinning technique
(2022-01-01)
Bootchanont, Atipong
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Porjai, Porramain
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Noonuruk, Russameeruk
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Wattanawikkam, Chakkaphan
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Pavasupree, Sorapong
Piezoelectric-assisted photocatalysis technology is one of the efficient ways to achieve enhancement in photocatalytic performance by facilitating the separation of photoinduced electron and holes via internal field initiated via piezoelectricity. Herein, bi-piezoelectric integrated effect was generated by the combination of piezoelectric semiconductor photocatalyst ZnO/Cu and piezoelectric polymer polyvinylidene fluoride (PVDF). Firstly, ZnO/Cu nanoparticles were prepared by facile co-precipitation method. Then, nanoparticles (at 10–30 wt%) were loaded in PVDF for fabricating nanofibers by electrospinning technique. All PVDF–ZnO/Cu nanofibers were characterized by XRD, FE-SEM, FTIR, XAS, and UV–Vis DRS. The structural study indicates that the β- and α-phase PVDF is observed in all the prepared nanofibers. XANES technique confirms the oxidation state of 2+ for Zn and Cu ions in both nanoparticles and nanofibers. Furthermore, under the synergy action of ultrasonic and visible light irradiation, PVDF–ZnO/Cu nanofibers exhibit superior piezo-photocatalytic degradation of rhodamine B dye when compared with single light or mechanical excitation. Effects of ZnO/Cu concentration on optical, piezoelectric, and photocatalytic properties are discussed.
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Phase formation, microstructure and electrical properties of Ba0.9Ca0.1TiO3 ceramics fabricated via the solid-state combustion technique
(2022-01-01)
Sonchaopri, Nutkamon
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Bhupaijit, Pamornnarumol
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Yotthuan, Surirat
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Sinkruason, Thanapon
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Premwichit, Pathit
In this research, the effects of calcination temperature in a range of 1050–1200 °C for 2 h and sintering temperature in a range of 1325-1400 °C for 2 h on phase formation, microstructure and electrical properties of lead-free Ba<inf>0.9</inf>Ca<inf>0.1</inf>TiO<inf>3</inf> (BCT) ceramics fabricated via the solid-state combustion technique were investigated. For the XRD result, all the ceramics exhibited a coexisting phase between tetragonal and orthorhombic. The ceramic grain size tended to increase with increase of the sintering temperature. For BCT ceramic produced by the optimum sintering temperature (1375 °C for 2 h), the dielectric, ferroelectric and piezoelectric properties of ε <inf>C</inf>=7393, P <inf>r</inf>=7.60 μC/cm2<inf>,</inf> E <inf>C</inf>=5.99 kV/cm and d <inf>33</inf>=158 pC/N, respectively, were obtained.
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Strain engineering and thermal conductivity of a penta-BCN monolayer: A computational study
(2021-09-01)
Dabsamut, Klichchupong
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Thanasarnsurapong, Thanasee
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Maluangnont, Tosapol
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T-Thienprasert, Jiraroj
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Jungthawan, Sirichok
Two-dimensional (2D) pentagonal nanostructures have been caught research attention down to their electronic, optical, mechanical and thermal transport properties. Among them, the newly proposed ternary penta-BCN monolayer shows a great potential for piezoelectric materials according to intrinsic piezoelectricity and spontaneous polarization. Nevertheless, the effect of strain toward these properties of the penta-BCN has not been elucidated. In this study, using density-functional theory with the Perdew-Burke-Ernzerhof (PBE) functional, we have investigated the impact of a uniform biaxial strain on the electronic structure and the thermal conductivity of the semiconducting penta-BCN single sheet. The strain-free penta-BCN monolayer is mechanically and dynamically stable with an indirect band gap of 1.70 eV. The sheet is rather soft as judged from the low in-plane Young's moduli. The pentagonal structure is preserved up to the yielding point of 18.4%, beyond this point the irreversible transition into the dynamically unstable, honeycomb-like system is observed. In contrast, the penta-BCN has dynamically instability under the compressive strain as small as -4%. The PBE band gap of the penta-BCN monolayer could be tuned within a range of 1.36-1.70 eV, falling into the infrared spectrum. The calculated lattice thermal conductivity of penta-BCN is around 97 W m-1 K-1 at temperature of 300 K, and decreases with increasing temperature.
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Dielectric and piezoelectric properties near the morphotropic phase boundary for 0.94BNT-0.06BT ceramics synthesized by the solid-state combustion technique
(2021-01-01)
Thatawong, Bhoowadol
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Bhupaijit, Pamornnarumol
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Lamyai, Yanwarood
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Vittayakorn, Naratip
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Bongkarn, Theerachai
Ceramics of 0.94Bi<inf>0.5</inf>Na<inf>0.5</inf>TiO<inf>3</inf>-0.06BaTiO<inf>3</inf> (0.94BNT-0.06BT) were synthesized by the solid-state combustion technique with various calcination and sintering temperatures (600-800 °C and 1100-1200 °C). A pure perovskite phase was obtained from the powder calcined at 750 °C for 2 h. The phase structure, microstructure, dielectric, ferroelectric and piezoelectric properties of the 0.94BNT-0.06BT ceramics were investigated. The XRD patterns showed coexisting phases of rhombohedral (R) and tetragonal (T) in all samples. Moreover, a good R:T phase ratio of 53:47, as found by Rietveld refinement, good grain growth and high density (5.84 g/cm3) were found with a sintering temperature of 1150 °C for 2 h. An excellent maximum dielectric constant (ε<inf>m</inf> = 8405), good ferroelectric properties (P<inf>r</inf> = 28.2 µC/cm2 and E<inf>c</inf> = 22.1 kV/cm) and a high piezoelectric coefficient (161 pC/N) were observed in this sample, which was near a morphotropic phase boundary (MPB).
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High-Performance Hybridized Composited-Based Piezoelectric and Triboelectric Nanogenerators Based on BaTiO3/PDMS Composite Film Modified with Ti0.8O2 Nanosheets and Silver Nanopowders Cofillers
(2019-05-28)
Sriphan, Saichon
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Charoonsuk, Thitirat
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Maluangnont, Tosapol
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Vittayakorn, Naratip
In order to commercialize the rapidly developing technology of energy harvesters, the following devices need to be developed further for enhancing output performance, flexibility, scalability, facile fabrication, and cheaper price. The composite-based triboelectric nanogenerator (CTENG), which contains the above properties, is a promising technology that has attracted special interest for a decade. Focus has been placed on the hybrid concept between the composite-based piezoelectric nanogenerator (CPENG) and CTENG in order to enhance CTENG efficiency. This study presented a high-performance hybridized CPENG and CTENG device, which operated from the composite film of Ti<inf>0.8</inf>O<inf>2</inf> nanosheets (Ti NSs)/silver nanoparticles (Ag NPs) co-doped BaTiO<inf>3</inf> nanopowders (BT NPOs) inside the polydimethylsiloxane (PDMS) host. The 0.3 vol % of Ti NSs and 1.5 vol % of Ag NPs exhibited the optimum harvesting performance in all compositions, with an output voltage and current density reaching approximately 150 V and 0.32 μA/cm2, respectively. Their harvesting performance was approximately 60 and 32 times higher than that of the CPENG constructed from pure PDMS. In addition, practical demonstration of the proposed device was investigated. The hybridized CPENG and CTENG device could operate in a long-term cyclic operation, charge the capacitor for storing energy, and also drive LEDs to brighten. This work suggested facile device fabrication and made a guideline to develop high-performance nanogenerators, which is crucial for device development and practical usage in the future.
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Piezoelectric-Induced Triboelectric Hybrid Nanogenerators Based on the ZnO Nanowire Layer Decorated on the Au/polydimethylsiloxane-Al Structure for Enhanced Triboelectric Performance
(2018-02-21)
Jirayupat, Chaiyanut
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Wongwiriyapan, Winadda
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Kasamechonchung, Panita
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Wutikhun, Tuksadon
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Tantisantisom, Kittipong
Here, we demonstrate a novel device structure design to enhance the electrical conversion output of a triboelectric device through the piezoelectric effect called as the piezo-induced triboelectric (PIT) device. By utilizing the piezopotential of ZnO nanowires embedded into the polydimethylsiloxane (PDMS) layer attached on the top electrode of the conventional triboelectric device (Au/PDMS-Al), the PIT device exhibits an output power density of 50 μW/cm2, which is larger than that of the conventional triboelectric device by up to 100 folds under the external applied force of 8.5 N. We found that the effect of the external piezopotential on the top Au electrode of the triboelectric device not only enhances the electron transfer from the Al electrode to PDMS but also boosts the internal built-in potential of the triboelectric device through an external electric field of the piezoelectric layer. Furthermore, 100 light-emitting diodes (LEDs) could be lighted up via the PIT device, whereas the conventional device could illuminate less than 20 LED bulbs. Thus, our results highlight that the enhancement of the triboelectric output can be achieved by using a PIT device structure, which enables us to develop hybrid nanogenerators for various self-power electronics such as wearable and mobile devices.
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Harvesting energy from a rotating gear using an AFM-Like MEMS piezoelectric frequency up-converting energy harvester
(2015-06-01)
Janphuang, Pattanaphong
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Lockhart, Robert A.
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Isarakorn, Don
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Henein, Simon
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Briand, Danick
This paper presents an analytical and experimental study of a compact configuration to harvest energy from a rotating gear using piezoelectric microelectromechanical system harvesters. The reported configuration realizes a contact-Type frequency up-conversion mechanism in order to generate useful electrical energy. The up-conversion mechanism was achieved using an atomic force microscope (AFM)-like piezoelectric cantilever plucked by the teeth of the rotating gear that could be eventually driven by an oscillating mass. This paper describes relevant design guidelines for harvesting energy from the low-frequency mechanical movement of a rotating gear through analytical modeling and finite element method (FEM) simulation followed by experimental validation. Different harvester configurations are investigated to identify the optimal configuration in terms of the output energy and energy conversion efficiency. The latter results are reported for the first time because of the implementation of an original concept based on the coupling of the harvester with a rotational flywheel. The experimental results reveal that free vibrations of the harvester after plucking contribute significantly to the output energy and efficiency. By adding a proof mass, the efficiency of the system can be greatly improved. For plucking speeds between 3 and 19 r/s, average output powers in the order of tens of microwatts were obtained for continuous plucking. By combining interaction energy, friction, and energy absorption, between the harvester and inertial mass, the maximum efficiency of the impact piezoelectric harvesters was found to be 1.4%. The efficiency results obtained were compared with the noncontact magnetic plucking approach further demonstrating the potential of our concept. Finally, different tip-gear materials combinations were evaluated showing the importance of their nature on the reliability of the presented configuration.

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