Phrompet, Chaiwat

Preferred name

Phrompet, Chaiwat

Alternative Name

Phrompet, C.

Main Affiliation

College of Innovation and Industrial Management

chaiwat.ph@kmitl.ac.th

Now showing 1 - 10 of 15

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Effect of rGO nanosheet loading in SiO2/rGO hybrid nanocomposites for enhancing optoelectrical, physical, and electrochemical properties
(2025-05-01)
Khammahong, Sunisar
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Phrompet, Chaiwat
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Ruttanapun, Chesta
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Sriwong, Chaval
In this study, silicon dioxide nanoparticles (SiO<inf>2</inf>NPs) mixed with reduced graphene oxide nanosheets (rGONS) and hybrid nanocomposites (S/rGOHNCs) were synthesized to study the opto-electrical, physical and electrochemical properties. S/rGOx%HNCs samples with rGONS at various loadings (10, 30, 50, and 70 wt%) were prepared SiO<inf>2</inf>NPs and rGONS suspensions in ultrasonication process by conventional heating. The SiO<inf>2</inf>NPs, rGONS and S/rGOx%HNCs were characterized and properties confirmed by XRD, Raman spectroscopy, FT-IR spectra, UV–Vis, SEM, EDX and TGA techniques. The electrical conductivity carrier concentration, energy gap, and dielectric constant increased with rGONS loading. The S/rGO30HNCs exhibited the highest thermal conductivity, 0.7 W/m·K, and Vickers microhardness, 41.0 HV. The value of electrochemical capacity of S/rGO70HNCs, 66.95 F/g, was due to the appropriate ratio of rGONS and SiO<inf>2</inf>NPs which significantly contributed to increasing redox reaction. The findings offered SiO<inf>2</inf>NPs mixed rGONS hybrid nanocomposites with enhanced optoelectrical (electrical, optical, dielectric), physical (mechanical, thermal) and electrochemical properties.
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Ferromagnetism of manganese-aluminium alloyed with 0–3% carbon from direct induction melting and subsequent annealing
(2020-01-01)
Charoensuk, Thanida
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Saetang, Panissa
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Ruttanapun, Chesta
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Phrompet, Chaiwat
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Pinitsoontorn, Supree
The transformation from ε to τ phase is investigated in manganese-aluminium (Mn<inf>55</inf>Al<inf>45</inf>) alloyed by the induction melting. By annealing Mn<inf>55</inf>Al<inf>45</inf> at 450–550°C for 2 h, the ferromagnetic τ-MnAl is enhanced at the expense of ε phase. The largest coercivity of 1139 Oe and remanent magnetization of 3.71 emu/g are obtained after annealing at 550°C. The additions of 1 and 2% carbon affect the phase and magnetic properties of Mn<inf>55</inf>Al<inf>45</inf> but the 2 h annealing at 550°C still leads to the largest coercivity. Interestingly, substantial coercivity and magnetizations are directly obtained in (Mn<inf>55</inf>Al<inf>45</inf>)<inf>98</inf>C<inf>2</inf> and (Mn<inf>55</inf>Al<inf>45</inf>)<inf>97</inf>C<inf>3</inf> by the induction melting without further heat treatments.
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Synthesis and electrochemical properties of activated lignite carbons-reduced graphene oxide nanocomposites symmetric supercapacitors
(2024-08-15)
Tuichai, Wattana
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Karaphun, Attaphol
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Phrompet, Chaiwat
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Chanlek, Narong
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Swatsitang, Ekaphan
Ultra-fast chargeable or rechargeable symmetric carbon-based supercapacitors (SCSs) with high capacity, inexpensive, and non-flammability have attracted much attention for electronics and energy storage devices. However, improving both high redox reaction and ion transport/diffusion processes by enhancing high energy storage performance and rapid ion/electron transport SCSs electrode materials remains challenging. Herein, we presented a successful preparation of activated lignite carbons-reduced graphene oxide (ALC-rGO) nanocomposite (NCp) with the ALC:rGO ratio of 80:20 wt% by a one-pot hydrothermal for high electrochemical performance. Importantly, the matrix of ALC-rGO NCp was primary amorphous carbon with hexagonal graphitic layers and pore structures of plentiful micropores and mesopores. Remarkably, the ALC-rGO NCp electrode exhibited a maximum specific capacitance (C<inf>sc</inf>) of 152.12 F/g at 0.5 A/g. Interestingly, the SCSs-ACL-rGO device could illustrate a good performance at a potential voltage of 1.8 V with C<inf>sc</inf> of 50.90 F/g at 1 A/g and capacity retention of 96.0 % at 5 A/g after 2,000 cycles GCD test.
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Microwave-activated reduced graphene oxide composite with hydrothermally treated corn husk activated carbon as an active electrode for high electrochemical performance in symmetrical carbon-based supercapacitor devices
(2026-07-01)
Srakaew, Khattiya
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Ratchayotee, Pornthip
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Janorat, Phattharawadee
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Phrompet, Chaiwat
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Kitiwan, Mettaya
This work applies microwaves for synthesizing reduced graphene oxide (rGO) and waste material corn husk activated carbon composites as active electrode materials for symmetric supercapacitors. The rGO is activated by microwave treatment and corn husk carbon by KOH in processed hydrothermal activation, followed by compositing at various weight ratios. Among all compositions, rGO:H_Corn_C (90:10) is reported with the best properties, with a specific surface area of 314.2 m2/g and a high specific capacitance of 1152 F/g at 0.1 A/g. The optimized composite also delivered increasing energy and power densities of up to 160 Wh/kg and 9.68 × 102 W/kg, respectively, within a 1 V operating window. In an experiment by assembling a symmetric coil cell supercapacitor, the device showed a specific capacitance of 142.23 F/g at 0.1 A/g, cycling stability with 98.8% capacitance retention after 1000 cycles of charge-discharge, and peak energy and power densities of 40.68 Wh/kg and 5.74 × 102 W/kg. Overall, the composite material with a high content of rGO and corn husk-derived activated carbon prepared by the hydrothermal method exhibits high-performance for the material in supercapacitor applications.
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Fabrication and thermoelectric conversion of thermoelectric concrete brick with buried unileg N-type CaMnO3 thermoelectric module inside
(2023-12-01)
Maneesai, Keerati
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Khammahong, Sunisar
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Siripoom, Pongsakorn
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Phrompet, Chaiwat
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Sriwong, Chaval
To investigate the effect of heat loss reduction due to thermal insulator and thermal interface resistance due to multi-layer structure in order to improve the efficiency of a thermoelectric device, a thermoelectric concrete brick was fabricated using a unileg n-type CaMnO<inf>3</inf> thermoelectric module inside. CaMnO<inf>3</inf> thermoelectric materials were synthesized by starting materials CaCO<inf>3</inf> and MnO<inf>2</inf> to produce a unileg n-type CaMnO<inf>3</inf> module. Thermoelectric concrete brick consisted of two types: I-layer brick (one layer of concrete thermal insulator) and III-layer brick (three layers of different concrete insulators). The occurring temperature difference, electric current and voltage on the CaMnO<inf>3</inf> module and thermoelectric concrete brick were measured in closed and open circuits. The temperature difference, thermal distribution, and output voltage when applying constant temperatures of 100, 200 and 400 °C were measured. Computer simulations of the Finite Element Method (FEM) were performed to compare with the experimental results. The trends of the temperature difference and the output voltage from the experimental and computer simulations were in good agreement. The results of the temperature difference during the hotter side temperature of 200 °C exhibited the temperature difference along the vertical direction of the thermoelectric concrete bricks for both types of the III-layer brick of 172 °C and the I-layer brick of 132 °C are larger than that of the CaMnO<inf>3</inf> TEG module without using a thermal concrete insulator of 108 °C. The thermoelectric concrete bricks of the III-layer brick type of 27.70 mV displayed output voltage results being higher than those of the I-layer brick of 26.57 mV and the CaMnO<inf>3</inf> TEG module without using a thermal concrete insulator of 24.35 mV. Thermoelectric concrete brick of the III-layer brick type displayed higher electric generation power than the I-layer brick and the CaMnO<inf>3</inf> TEG module. Additionally, the results exhibited the capability of thermoelectric concrete brick in the III-layer brick model for electric generation power based on the temperature difference. The TEG concrete brick of I-layer concrete covering the series–parallel combination circuit of 120 modules of the unileg n-type CaMnO<inf>3</inf> was constructed and then embedded on the outer surface of the furnace. During the maximum hotter side temperature of 580 °C of the concrete brick, the temperature difference between the hotter side and the cooler side of the brick occurred at 365 °C and the maximum output voltage was obtained at 581.7 mV.
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The Mechanical and Thermal Properties of Cement CAST Mortar/Graphene Oxide Composites Materials
(2022-12-01)
Janjaroen, Thidatip
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Khammahong, Sunisar
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Tuichai, Wattana
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Karaphun, Attaphol
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Phrompet, Chaiwat
This paper presents the influence of the graphene oxide (GO) sheet contents at conditions of 0, 0.01, 0.03, 0.05, and 0.1 wt% on the mechanical and thermal properties of GO/CAST 11 LW mortar (GMT) composites for heat insulating brick. The GMT composites were prepared by a simple mixing method. The structure of GMT composites was investigated by X-ray diffraction (XRD) and Raman spectroscopy (Raman) techniques. The small grain sizes of GMT composites were confirmed by transmission electron microscopy (TEM). The mechanical properties of GMT composites are increased with increasing GO contents. A lot of functional groups in GO such as carboxylic acid reacted with a calcium silicate hydrate, CaH<inf>2</inf>O<inf>4</inf>Si (CSH), calcium hydroxide, Ca(OH)<inf>2</inf> (CH) and Ettringite, and Ca<inf>6</inf>[Al(OH)<inf>6</inf>]<inf>2</inf>(SO<inf>4</inf>)<inf>3</inf>·26H<inf>2</inf>O (CA) phases in the mortar, which can be considered good mechanical properties in the GMT composites. The heat insulation values of GMT composites were improved by the interaction with the CSH, CH, and CA phases in the cement mortar on the surface of GO. The highest compressive and tensile strengths and low heat transfer rate of about 0.465 W/min were observed at 0.05 of GO (GMT_0.05) composites in the curing age of 7 days. Thus, a new pathway of GMT composites can be prepared by a simple mixing method to significantly improve the mechanical and thermal properties of mortar GMT composites.
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Influence of free electron charge and free extra framework anions in calcium aluminate@ rGO (CA@ rGO) cement composites with enhanced dielectric and electrochemical properties
(2021-10-01)
Ruttanapun, Chesta
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Phrompet, Chaiwat
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Tuichai, Wattana
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Karaphun, Attaphol
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Daengsakul, Sujittra
Nowadays, the metal oxide-based composites loaded with reduced graphene oxide (rGO) nano sheets are believed to enhance both the electrochemical and dielectric properties. In this study, therefore, the effect of rGO loading contents on the calcium aluminate (CA), namely CA@ rGO, cement composites with high dielectric and electrochemical properties is presented. CA@ rGO composites were successfully synthesized via a simple direct mixing of CA cement with various contents of graphene oxide (GO) precursors followed by a conventional thermal reduction method. Based on XRD and Raman spectroscopy results, all prepared CA@ rGO composites clearly confirmed both the structure of the pristine CA cement as well as the complete conversion of GO precursors to rGO after thermal reduction, and the existence of rGO nano sheets on the surface of CA@ rGO composites. The impedance value results revealed that the enhancement of a high dielectric constant was achieved in the CA@ rGO composites due to both typical interface polarization and the micro-capacitor of CA cement and rGO nano sheets. Meanwhile, the prepared CA@ rGO-4 composite electrode exhibited the highest of electrochemical double-layer capacitive behavior with the specific capacitance (C<inf>sc</inf>) value of 79.33 F g−1 at 0.2 A g−1. The enhanced super-capacitive performance of CA@ rGO composite can be improved by the synergistic effect of free electron transfer and electron diffusion between the CA cement interface and rGO nano sheets.
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Temperature-dependent electrical transport, Hall effect, and Seebeck properties of bulk chemically reduced graphene oxide with bipolar charge carrier materials
(2023-03-01)
Maneesai, Keerati
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Silakaew, Kanyapak
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Khammahong, Sunisar
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Phrompet, Chaiwat
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Sriwong, Chaval
The temperature-dependent electrical transport, Hall effect, and Seebeck properties of bulk-reduced graphene oxide (rGO) prepared by a chemical reduction process were investigated in a temperature range of 310-475 K. The bulk rGO contained bipolar charge carriers with p-type to n-type switching at a temperature of 420 K. The materials illustrated a p-type characteristic in the temperature range of 310-420 K and n-type characteristic in the temperature range of 420-475 K. The charge transport mechanism was that of the graphene-derived 2D material in the p-type regime and governed by polaronic charge carriers.
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Electrochemical properties of tricalcium aluminate hexahydrate − reduced graphene oxide nanocomposites for supercapacitor device
(2020-08-01)
Phrompet, Chaiwat
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Maneesai, Keerati
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Tuichai, Wattana
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Karaphun, Attaphol
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Sriwong, Chaval
In this study, the influence of reduced graphene oxide (rGO)−Tricalcium Aluminate Hexahydrate (C3AH6) cement nanocomposites on electrochemical properties was investigated. The rGO-C3AH6 nanocomposite samples with various of rGO laoding, such as, C3AH6_rGO-1, 3, 5, 7, 10 and 20 wt.% were easily synthesized by a rapid cement hydration method. The maximum specific surface area and average pore size diameters were 74.20 m2/g and 11.72 nm for C3AH6_rGO-20%. The charge tranfering in C3AH6_rGO nanocomposites was described using band alignments model occurring between C3AH6 and rGO. Interestingly, the increasing of both dielectric property and stability in frequency of C3AH6_rGO composite samples can be explained by the high density of free electron charges on the rGO surface. Moreover, the electrochemical properties of C3AH6_rGO electrodes had excellent capacitive properties displaying the storage charge mechanism of a hybridsupercapacitor behavior. The large rGO content of the C3AH6_rGO nanocomposite capacitor with electrolyte interfaces showed excellent electrochemical performance. The highest value of 80.479 F g −1 was obtained from C3AH6_rGO-20% at a current density of 0.2 A g −1 with cycling stability of 96.51% after 1000 cycles.
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Synthesis, microstructure, multifunctional properties of mayenite Ca12Al14O33 (C12A7) cement and graphene oxide (GO) composites
(2020-12-01)
Sriwong, Chaval
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Phrompet, Chaiwat
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Tuichai, Wattana
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Karaphun, Attaphol
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Kurosaki, Ken
The Pristine Mayenite Ca<inf>12</inf>Al<inf>14</inf>O<inf>33</inf> (C12A7) Cement was simply synthesized by using solid-state reaction. The C12A7 and Graphene Oxide (GO) composites (C12A7_GO-x) with various contents of the GO suspension loading (x = 0 wt%, 1 wt%, 2 wt%, 3 wt%, and 4 wt%) were directly prepared by mixing the C12A7 and GO. X-ray diffraction results of pristine C12A7 and all C12A7_GO composites indicated a pure phase corresponding to the standard of C12A7 cement. Raman spectroscopy confirmed the existence of GO in all C12A7_GO samples. Scanning Electron Microscopy (SEM) showed the micrometer grain sizes and the occurrence of grain boundary interfaces for GO incorporation in all C12A7_GO samples. UV–Vis spectroscopy revealed the absorption value of all C12A7_GO samples and red shift near longer wavelengths when increasing the GO concentrations. The dielectric constant of C12A7_GO composites can be explained by the high density of free electron charges for the interfacial polarization on the GO surface. The maximum specific capacitance of C12A7_GO-4 electrode of 21.514 at a current density of 0.2 A g−1 can be attributed to the increase in the electrochemically active surface area for the formation of the electrical double layer capacitors behavior and the effects of high surface area GO connections. Also, the mechanical properties exhibited an increase in Vickers indenter hardness (HV) values with increasing GO contents. The highest HV value was 117.8 HV/2 kg at the C12A7_GO-4 sample. These results showed that the composite materials of the pristine C12A7 cement with GO were highly efficient. All in all, the GO material contained a high potential for enhancing low-cost cement materials in multifunctional properties such as optical, dielectric, electrochemical, and mechanical properties.

Phrompet, Chaiwat

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