KMITL

Permanent URI for this communityhttps://dspace.kmitl.ac.th/handle/123456789/1

Browse

Settings

Author: search.filters.author.Kraiwattanawong, K.

Search Results

Now showing 1 - 3 of 3
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Publication,
    Methylene blue degradation under visible light of Au-DP25/PET and Cu-DP25/PET photocatalytic films, synthesized through two wet impregnation routes – An experimental and theoretical evaluation
    (2023-12-01)
    Cheunwisat, P.
    ;
    Kraiwattanawong, K.
    ;
    Saelee, T.
    ;
    Rittiruam, M.
    ;
    Praserthdam, S.
    Two wet impregnation methods (W-I and W-II) were employed to develop Cu-DP25/PET and Au-DP25/PET photocatalytic films. The W-I method based on the synthesis of M-TiO<inf>2</inf> powders (DP25 decorated with metal) followed by the sono-deposition on PET sheets. The W-II method begins with the sono-deposition of DP25 onto PET sheets, followed by the sono-deposition of M-TiO<inf>2</inf> solution (DP25 +Metal+H<inf>2</inf>O). Under visible light, the Cu-DP25/PET and Au-DP25/PET films via W-II exhibited superior photocatalytic activity. The photocatalytic activity was studied by analyzing the degradation of methylene blue (MB) under visible light. The materials were characterized with the employing of scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDX), X-ray diffraction (XRD), transmission electron microscopy (TEM), UV–vis DRS (UV–Vis) spectroscopy, and photoluminescence (PL). The interactions between catalysts/environment were studied through molecular dynamics simulation (MD) and binding energies (E<inf>binding</inf>). The superior photodegradation of Au-DP25/PET films towards MB was attributed to the combination of two effects: LSPR (localized surface plasmon resonance) and Au-TiO<inf>2</inf>/environment affinities. The aim of the experimental/theoretical analysis was to provide a deep understanding of the medium/surface interactions on decorated TiO<inf>2</inf> materials and how these interactions influence the overall degradation behavior.
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Publication,
    Improvement of mesopore structure of resorcinol and formaldehyde carbon cryogels by acid solution
    (2008-01-01)
    Kraiwattanawong, K.
    ;
    Kitchaiya, P.
    ;
    Neramittagapong, A.
    ;
    Praserthdam, P.
    ;
    Tamon, H.
    Resorcinol and formaldehyde (RF) carbon cryogels are prepared by sol-gel polycondensation by using sodium carbonate (C) as a catalyst with water (W) as solvent, immersed in acid solution, hydrochloric acid (HC1), dried by freeze-drying technique and then carbonized under inert atmosphere, respectively. Compared with their carbon precursors, both V<inf>mes</inf> and mesopore size distributions of all carbon cryogels can be developed since the pore shrinkage is the crucial role in the change of pore structure of carbon gels. HC1 may promote the strength of small pore structure and increase the pore shrinkage of large pore structure. Consequently, the treatment of HC1 does not only enhance the partial collapse of large pore structure, the treatment also increases the strength of small pore structure to inhibit the shrinkage of this structure during carbonization as well. © 2008 Trans Tech Publications, Switzerland.
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Publication,
    Preparation of carbon cryogels from wattle tannin and furfural
    (2007-01-05)
    Kraiwattanawong, K.
    ;
    Mukai, S. R.
    ;
    Tamon, H.
    ;
    Lothongkum, A. W.
    Wattle tannin-furfural (TFu) hydrogels were synthesized by the sol-gel polycondensation of wattle tannin with furfural by using three types of base catalysts (NaOH, Na<inf>2</inf>CO<inf>3</inf> and NaHCO<inf>3</inf>). TFu cryogels were prepared by freeze drying of the hydrogels and TFu carbon cryogels were obtained by pyrolysis of the cryogels in an inert atmosphere. The TFu and carbon cryogels were characterized by N<inf>2</inf> adsorption and scanning electron microscope (SEM). The effect of catalysts on porous properties of carbon cryogels resulted in different ways: (1) NaOH enhances increasing mesopore volumes and surface area of carbon cryogels and (2) Na<inf>2</inf>CO<inf>3</inf> and NaHCO<inf>3</inf> cause decreasing those of carbon cryogels. The TFu and carbon cryogels prepared by using NaOH as a catalyst possessed large mesopore volumes comparing with micropore volumes. Even though the TFu cryogels have surface area and mesopore volumes smaller than the resorcinol-formaldehyde (RF) cryogels, the carbon cryogels have unique porous properties differed from the RF carbon gels. The properties are summarized as follows: (1) the mesopore volume changes insignificantly after pyrolysis, (2) the pore radius is increased after pyrolysis and (3) micropores are not greatly developed during pyrolysis. © 2006 Elsevier Inc. All rights reserved.