Pecharapa, Wisanu

Preferred name

Pecharapa, Wisanu

Alternative Name

PECHARAPA, Wisanu

Pecharapa, W.

Main Affiliation

Integrated Innovative Technology

wisanu.pe@kmitl.ac.th

Now showing 1 - 10 of 19

Some of the metrics are blocked by your
consent settings
Characterization and x-ray absorption spectroscopy of ilmenite nanoparticles derived from natural ilmenite ore via acidassisted mechanical ball-milling process
(2017-09-01)
Phoohinkong, Weerachon
;
Pavasupree, Sorapong
;
Wannagon, Anucha
;
Sanguanpak, Samunya
;
Boonyarattanakalin, Kanokthip
In this work activated ilmenite nanoparticles were prepared by chemical-assisted in mechanical ball-milling process from ilmenite ore as starting raw material. The effect of milling process on their phase composition, particle size, surface morphology and local structure were investigated. Phase identification and crystalline structure of ilmenite mineral, milled samples and subsequent leached residues were characterized by x-ray diffraction (XRD). Meanwhile, the distorted octahedral structure and the oxidation state of relevant elements in ilmenite ore and activated ilmenite obtained by different process conditions were analyzed by x-ray absorption spectroscopy (XAS). Particle size and morphologies of the samples were monitored by field emission scanning electron microscope (FESEM) and transmission electron microscope (TEM). Three dominant peaks of TiO2 rutile, FeTiO<inf>3</inf>, and Fe<inf>2</inf>TiO<inf>4</inf> are obviously adulterated in XRD patterns after mechanical milling with water and acid solution when comparing to precursor mineral. However, the contaminated phase of FeTiO3 and Fe<inf>2</inf>TiO<inf>4</inf> was readily decreased by acid-assisted mechanical ball-milling. The enhancement in leaching process of ilmenite residue after milling can be obtained with sulfuric acid. This result suggests that iron contaminated phase could be leached from the sample resulting to the decrease in Fe environment around Ti atom.
Some of the metrics are blocked by your
consent settings
Characterization of flower-like titanate and titania nanowires on titanium plate substrate
(2013-01-01)
Pavasupree, Sorapong
;
Onoda, Kinji
;
Yoshikawa, Susumu
;
Simpraditpan, Athapon
;
Pecharapa, Wisanu
Flower-like structure titanate and titania on titanium plate substrate composed of nanowires were synthesized by hydrothermal method at 150 oC for 2 h using titanium plate substrate as the starting material. The crystalline structure, shape and size of the prepared sample were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). SEM images showed flower-like structure with uniform size about 2 ?m. The flower-like structure composed of nanowires with diameter about 20-50 nm. Titanate and titania could be controlled by washing process and calcination temperature. This synthesis method provides a simple route to fabricate nanostructured titanate and titania on titanium plate substrate for dye-sensitized solar cell and photocatalytic activity applications. © 2013 The Authors. Published by Elsevier B.V.
Some of the metrics are blocked by your
consent settings
Characterization, X-ray absorption spectroscopic analysis and photocatalytic activity of Co/Zn co-doped TiO2 nanoparticles synthesized by one-step sonochemical process
(2021-10-01)
Mekprasart, Wanichaya
;
Pavasupree, Sorapong
;
Jayasankar, C. K.
;
Ravuri, Balaji Rao
;
Wattanawikkam, Chakkaphan
A novel one-step preparation of sonochemical method was applied to synthesize Co/Zn co-doped TiO<inf>2</inf> nanoparticles using a sonicator of 750 W, 20 kHz for 30 min at room temperature. The formation of the anatase TiO<inf>2</inf> phase for all as-prepared samples was observed from XRD results with a crystalline size in nanoscale. The use of ultrasound allowed for the successful doping of both Co and Zn into the TiO<inf>2</inf> lattice, which was confirmed by Synchrotron light including X-ray near edge structure (XANES) and Extended X-ray absorption fine structure (EXAFS) spectroscopy. Ti K-edge, Co K-edge, and Zn K-edge XANES spectra exhibited the dominating +4, +2, and +2 valence state of Ti, Co, and Zn in as-prepared samples, respectively. A detailed XANES and EXAFS data analysis give strong evidence that the Co/Zn dopants partially replace the Ti atom of the TiO<inf>2</inf> host. The Co/Zn co-doping extends the light absorption of the host to the visible region and restricts the e+/h+ recombination. The photocatalytic activity of samples was tested for degradation of Rhodamine B dye solution under visible light irradiation. The as-synthesized of the co-doped catalyst was presented as highly efficient, with 2.5 and 5 times dye degradation compared with single-doped and bare TiO<inf>2</inf>.
Some of the metrics are blocked by your
consent settings
Synergistic effects of biomass-derived carbon quantum dots and Cu Co-doping on TiO2 nanocomposite for enhanced visible-light photocatalysis
(2026-12-01)
Zhao, Huali
;
Noonuruk, Russameeruk
;
Bootchanont, Atipong
;
Porjai, Porramain
;
Thongpool, Voranuch
The development of sustainable approaches for enhancing the visible-light activity of TiO<inf>2</inf>-based photocatalysts has attracted considerable research interest. In this work, carbon quantum dots (CQDs)-Cu co-modified TiO<inf>2</inf> nanocomposites were synthesized via a hydrothermal method using butterfly pea ( Clitoria ternatea ) flowers as a biomass-derived carbon source. The Cu content was fixed at 1.5 mol% relative to Ti, while the CQDs loading was controlled by varying the butterfly pea precursor concentration from 0.25 to 1.25 g L−1, yielding 1C–Cu–TiO<inf>2</inf>, 3C–Cu–TiO<inf>2</inf>, and 5C–Cu–TiO<inf>2</inf> samples. The prepared materials were characterized by electron microscopy, X-ray diffraction (XRD), UV–vis diffuse reflectance spectroscopy, photoluminescence (PL), and X-ray absorption spectroscopy (XAS). High-resolution transmission electron microscopy revealed CQDs with an average size of approximately 4.29 nm and an interplanar spacing of approximately 0.23 nm. All composites retained the anatase TiO<inf>2</inf> phase after Cu incorporation and CQDs modification. Enhanced visible-light absorption was observed and is attributed to the formation of Cu-related sub-band-gap states and the sensitization effect of CQDs. PL analysis showed an emission peak at ∼415 nm under 660 nm excitation, suggesting the presence of upconversion photoluminescence behavior in the CQDs. Conventional PL spectra further suggested reduced charge-carrier recombination in the modified composites. Photocatalytic activity was evaluated through Rhodamine B (RhB) degradation under visible-light irradiation. Among all samples, 1C–Cu–TiO<inf>2</inf> exhibited the highest performance, achieving degradation efficiency of 99.28% within 50 min. The apparent reaction rate constant reached 0.1038 min−1, which was 2.23, 1.96, and 2.90 times higher than those of pristine TiO<inf>2</inf>, Cu–TiO<inf>2</inf>, and 3C–Cu–TiO<inf>2</inf>, respectively. Radical scavenging experiments indicated that •OH and h+ were the dominant reactive species, while •O<inf>2</inf>− also participated in the degradation process. The enhanced photocatalytic performance is attributed to the synergistic effects of Cu and biomass-derived CQDs in improving visible-light harvesting and charge separation, providing an effective approach for developing visible-light-responsive TiO<inf>2</inf> photocatalysts.
Some of the metrics are blocked by your
consent settings
Piezoelectric enhanced photocatalytic properties of PVDF–ZnO/Cu nanofibers prepared by electrospinning technique
(2022-01-01)
Bootchanont, Atipong
;
Porjai, Porramain
;
Noonuruk, Russameeruk
;
Wattanawikkam, Chakkaphan
;
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.
Some of the metrics are blocked by your
consent settings
Extraction and characterization of nanocellulose from sugarcane bagasse by ball-milling-assisted acid hydrolysis
(2018-09-05)
Plermjai, Kittiya
;
Boonyarattanakalin, Kanokthip
;
Mekprasart, Wanichaya
;
Pavasupree, Sorapong
;
Phoohinkong, Weerachon
This study is proposed to characterize nanocellulose extracted from sugarcane bagasse (SCB). For extracting cellulose, the bagasse was treated by chemical treatment. The nanocellulose was prepared using ball-milling with acid hydrolysis. Morphology of bagasse, cellulose and nanocellulose were characterized by scanning electron microscopy (SEM). The chemical composition of extracted cellulose and nanocellulose was investigated by Fourier-transformed infrared spectroscopy that verifying the removal of lignin and hemicellulose during cellulose isolation process from sugarcane bagasse. The crystalline structure of cellulose and nanocellulose were characterized by X-ray diffraction (XRD), indicating that the nanocellulose prepared by ball milling with acid hydrolysis has higher crystallinity than nanocellulose prepared only ball milling.
Some of the metrics are blocked by your
consent settings
Effect of calcination temperature on structure and photocatalytic activity under UV and visible light of nanosheets from low-cost magnetic leucoxene mineral
(2017-07-01)
Charerntanom, Wissanu
;
Pecharapa, Wisanu
;
Pavasupree, Suttipan
;
Pavasupree, Sorapong
This research has experimentally synthesized the nanosheets from the naturally-mineral magnetic leucoxene under the hydrothermal synthesis condition of 105 °C for 24 h. Magnetic leucoxene was utilized as the starting material due to its high TiO<inf>2</inf> content (70–80%) and inexpensiveness. The characterization of the synthesized nanosheets was subsequently carried out: the crystalline structure, the chemical composition, the shape, the size and the specific surface area, by the X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Brunauer–Emmett–Teller (BET) specific surface area analysis. The analysis results indicated that the starting magnetic leucoxene is of rutile phase while the synthesized nanosheets are of titanate structure (H<inf>2</inf>Ti<inf>x</inf>O<inf>2x + 1</inf>). After calcination at the temperature range of 300 and 400 °C, the calcined samples demonstrated TiO<inf>2</inf> (B). At 500 and 600 °C, the calcined nanosheets revealed a bi-crystalline mixture consisting of TiO<inf>2</inf> (B) and anatase TiO<inf>2</inf>. At 700–1000 °C, the crystalline structure shows anatase and rutile phase. At 1100 °C, the prepared samples consisted of a mixture of anatase, rutile phase of TiO<inf>2</inf>, and Fe<inf>2</inf>O<inf>3</inf> phase. The synthesized product also exhibited the flower-like morphology with 2–5 μm in diameter, and the nanosheets structure was slightly curved, with 100 nm to 2 μm in width and 1–3 nm in thickness. At 100–200 °C showed sheets-like structure. At 300–1100 °C, the calcined nanosheets became unstable and began to decompose and transform into nanoparticles. The increasing size of nanoparticle decreased the specific surface area of the nanosheets, caused by increasing calcination temperature. Furthermore, the BET specific surface area of the nanosheets was approximately 279.8 m2/g. More importantly, the synthesized nanosheets achieved the higher photocatalytic activity under UV and visible light than did the commercial TiO<inf>2</inf> nanoparticles (JRC-01, JRC-03, ST-01 and P-25).
Some of the metrics are blocked by your
consent settings
Efficiency enhancement in dye-sensitized solar cell using TiO2 /ilmenite-derived nanofiber composite as working electrode
(2014-01-01)
Simpraditpan, Athapon
;
Wirunmongkol, Thanakorn
;
Pavasupree, Sorapong
;
Pecharapa, Wisanu
TiO<inf>2</inf> nanocomposite films of calcined TiO<inf>2</inf> nanofibers and commercial-grade TiO<inf>2</inf> nanoparticles Degussa (P25) utilized as working electrode of dye-sensitized solar cells (DSSCs) are prepared by a doctor blade method. TiO<inf>2</inf> nanofibers were synthesized from ilmenite mineral by hydrothermal process in combination with calcinations process. The prepared samples are characterized by XRD, XPS and TEM. The photoelectric conversion performance of the DSSC based on nanocomposite film electrode was compared to the device fabricated by pure P25 at the same film thickness. The result shows that as calcination temperature increases, the transformation of nanofibers to nanorods and nanoparticles were observed. The energy conversion efficiency ({eng}) of the device tends to with increasing calcined temperature. The greatest {eng} is 3.90% obtained from DSSC fabricated from nanocomposite film electrode of 5 wt.% nanofibers calcined at 800 °C for 2 h mixed with P25, indicating the significant enhancement in its performance by the incorporation of the nanofibers. This enhancement of DSSCs may correlate to high surface area, higher light scattering and light harvesting, low charge recombination and fast electron-transfer rate by nanofibers. © (2014) Trans Tech Publications, Switzerland.
Some of the metrics are blocked by your
consent settings
Optical absorption and FTIR study of cellulose/tio2hybrid composites
(2019-05-01)
Plermjai, Kittiya
;
Boonyarattanakalin, Kanokthip
;
Mekprasart, Wanichaya
;
Phoohinkong, Weerachon
;
Pavasupree, Sorapong
Cellulose/TiO<inf>2</inf> composite was prepared by conventional mixing using distilled water as medium. The structure and relevant properties of cellulose/TiO<inf>2</inf> composite were characterized by X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and UV- Vis spectroscopy. XRD results exhibit typical cellulose structure type I. The absorbance spectra of TiO<inf>2</inf>and cellulose exist in vicinity of 200 nm and 350 nm in the UV range, corresponding to the UV-C, UV-B and UV-A. In addition, the UV absorption band of the composite can be extended covering wide UV region. Corresponding FTIR results suggest the existence of chemical bonding or surface interaction between TiO<inf>2</inf> and cellulose.
Some of the metrics are blocked by your
consent settings
Nonlocal XANES pre-edge feature of FeTiO3 ilmenite-type at Ti and Fe K-edge
(2020-09-01)
Phoohinkong, Weerachon
;
Boonyarattanakalin, Kanokthip
;
Mekprasart, Wanichaya
;
Pavasupree, Sorapong
;
Pecharapa, Wisanu
The pre-K-edge feature of Ti and Fe XANES of ilmenite FeTiO<inf>3</inf> were investigated. The electronic structure of FeTiO<inf>3</inf> was examined based on the partial density of electronic state distribution on both local and nonlocal atoms. A strong contribution of nonlocal metal-metal intervalence electronic states of Ti and Fe pre-K-edge was observed in X-ray absorption near-edge structure (XANES) measurement. This observation agrees well with the calculated local state density. The nonlocal excitation transitions in the pre-edge feature contribute to local pre-K-edge at both Ti and Fe. Ti pre-K-edge consists of highly hybridized Ti-3d(t<inf>2g</inf>) with a small part of dipole-allowed 4p and a small 4s density transition state feature which is predominated by nonlocal of Fe-3d mixed with 4p state delocalized via O-2p as the main component peak. The peak feature at Ti-3d(e<inf>g</inf>) energy state is assigned to hybridization of Ti-3d(e<inf>g</inf>) and Ti-4p state contributed with nonlocal of the hybridized Fe-sp and the Ti-pd state. Fe pre-K-edge shows two main prominent transition peaks of hybridized Fe-pd state and the delocalized local Fe-sp with nonlocal Ti-3d(t<inf>2g</inf>) and 4p mixing states centered at 7112.38 and 7116.48 eV, respectively. The local and nonlocal excited transition energy states and density of both Ti pre-K-edge and Fe pre-K-edge features are corresponded with each other through the O-2p state transition pathway.

Pecharapa, Wisanu

Filters

Settings

Sort By

Results per page