Browsing by Author "Kanokthip Boonyarattanakalin"

Now showing 1 - 3 of 3
  • Default Image
    Item
    Adsorbed protein on P25 nanoparticles-synthesis, characterization and electrochemical property
    (American Institute of Physics Inc., 2018) Weerachon Phoohinkong; Thitinart Sukonket; Kanokthip Boonyarattanakalin; W. Phoohinkong; Faculty of Science and Technology, Suan Dusit University, Bangkok, 10700, Thailand; email: p_veerachon@hotmail.com
    Keratin modification on surface of titanium dioxide P25 was carried out from titanium dioxide suspension and keratin solution extracted from swine wool. The existence of amide component, protein functional groups dissociated to active protein moieties and attached to titanium dioxide surface in form of hybrid nanomaterial were characterized by Fourier-transform infrared spectroscopy (FT-IR). The keratin protein decorated on particle surfaces was observed by Field Emission Scanning Electron Microscopy (FESEM). Chemical states and bonding at the nano-biomolecule interfaces with titanium dioxide were investigated using X-ray Photoelectron Spectroscopy (XPS). Protein concentration is considered as roles for protein modification, surface bonding, chemical states and protein adsorption. The Ti3+ and Ti2+ surface and high adsorption degree can be obtained at low concentration of protein solution with P25. However, the strong bonding between protein and TiO2 obtained in high protein concentration with Ti3+ and Ti2+ species result disappear for Ti3+ and Ti2+ XPS peaks. The adsorbed protein reveals secondary structure of random coil keratin with strong bonding conjugated to the titanium dioxide surface. The strong binding between protein and TiO2 surface in this novel protein-TiO2 hybrid material shows a promising alternative way for advance tunable electronic structure and charge transport mechanism which enhance electrochemical capacitance by mean of double layer and pseudo-capacitive behavior. � 2018 Author(s).
  • Default Image
    Item
    Nonlocal XANES pre-edge feature of FeTiO3 ilmenite-type at Ti and Fe K-edge
    (Elsevier Ltd, 2020) Weerachon Phoohinkong; Kanokthip Boonyarattanakalin; Wanichaya Mekprasart; Sorapong Pavasupree; Wisanu Pecharapa; W. Pecharapa; College of Nanotechnology, King Mongkut's Institute of Technology Ladkrabang, Ladkrabang, 10520, Thailand; email: kpewisan@gmail.com
    The pre-K-edge feature of Ti and Fe XANES of ilmenite FeTiO3 were investigated. The electronic structure of FeTiO3 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(t2g) 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(eg) energy state is assigned to hybridization of Ti-3d(eg) 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(t2g) 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. © 2020 Elsevier Ltd
  • Default Image
    Item
    Optical absorption and FTIR study of cellulose/tio2hybrid composites
    (Chiang Mai University, 2019) Kittiya Plermjai; Kanokthip Boonyarattanakalin; Wanichaya Mekprasart; Weerachon Phoohinkong; Sorapong Pavasupree; Wisanu Pecharapa; W. Pecharapa; College of Nanotechnology, King Mongkut�s Institute of Technology Ladkrabang, Bangkok, 10520, Thailand; email: kpewisan@gmail.com
    Cellulose/TiO2 composite was prepared by conventional mixing using distilled water as medium. The structure and relevant properties of cellulose/TiO2 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 TiO2and 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 TiO2 and cellulose. � 2019, All Right reserved.