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Dye mixing effects on photocatalytic water splitting activity on dye-modified KTaO3 catalyst / Hidehisa Hagiwara in Transactions of the ASME. Journal of solar energy engineering, Vol. 132 N° 2 (Mai 2010) 

Public ISBD [article]  in Transactions of the ASME. Journal of solar energy engineering > Vol. 132 N° 2 (Mai 2010) . - pp. [021201/1-5] Titre : Dye mixing effects on photocatalytic water splitting activity on dye-modified KTaO3 catalyst Type de document : texte imprimé Auteurs : Hidehisa Hagiwara, Auteur ; Hiroshige Matsumoto, Auteur ; Tatsumi Ishihara, Auteur Année de publication : 2011 Article en page(s) : pp. [021201/1-5] Note générale : Energie Solaire Langues : Anglais (eng) Mots-clés : Photocatalyst  Water  splitting  Prorphyrin  Dye  mixing  Change  transfer Index. décimale : 621.47 Résumé : Dye mixing effects on water splitting activity of KTaO3 photocatalyst modified by various porphyrinoids was investigated. Photocatalytic activity of dye-modified KTaO3 catalyst is greatly improved by mixing various porphyrinoids, in which transition metals such as Cr, Fe, and Co are used as central metal. Pentametylene bis[4-(10, 15, 20-triphenyl porphine-5-yl) benzoate]-dizinc(II) (Zn-TPP dimer) showed positive effect on photocatalytic activity, and H2 and O2 formation rates are 365 µmol g h−1 and 152 µmol g h−1, respectively. On the other hand, the combination of chloroprotoporphyrinato iron (III) (chlorohemin) with Cr-phthalocyanine (CrPc) is the most effective for increasing water splitting activity, and the formation rates of H2 and O2 are 2.12 mmol g h−1 and 1.11 mmol g h−1, respectively. Energy conversion efficiency of this photocatalyst is estimated to be approximately 0.05%. From X-ray photoelectron spectroscopy measurement and cyclic voltammetry of organic dyes, it is suggested that the electronic state of the dye mixture is modified compared with that of a single dye. Energy transfer between mixing dyes is observed in the fluorescence spectra of dye-modified KTaO3 photocatalysts. Recombination of photoexited charge in KTaO3 is clearly suppressed by dye mixing, thus improvement of photocatalytic activity is attributed to the lengthening of excitation lifetime. This study reveals that mixing porphyrinoid dyes is an effective method for increasing water splitting activity of dye-modified KTaO3 photocatalysts. DEWEY : 621.47 ISSN : 0199-6231 En ligne : http://asmedl.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JSEEDO00013200 [...] [article] Dye mixing effects on photocatalytic water splitting activity on dye-modified KTaO3 catalyst [texte imprimé] / Hidehisa Hagiwara, Auteur ; Hiroshige Matsumoto, Auteur ; Tatsumi Ishihara, Auteur . - 2011 . - pp. [021201/1-5]. Energie Solaire Langues : Anglais (eng) in Transactions of the ASME. Journal of solar energy engineering > Vol. 132 N° 2 (Mai 2010) . - pp. [021201/1-5] Mots-clés : Photocatalyst  Water  splitting  Prorphyrin  Dye  mixing  Change  transfer Index. décimale : 621.47 Résumé : Dye mixing effects on water splitting activity of KTaO3 photocatalyst modified by various porphyrinoids was investigated. Photocatalytic activity of dye-modified KTaO3 catalyst is greatly improved by mixing various porphyrinoids, in which transition metals such as Cr, Fe, and Co are used as central metal. Pentametylene bis[4-(10, 15, 20-triphenyl porphine-5-yl) benzoate]-dizinc(II) (Zn-TPP dimer) showed positive effect on photocatalytic activity, and H2 and O2 formation rates are 365 µmol g h−1 and 152 µmol g h−1, respectively. On the other hand, the combination of chloroprotoporphyrinato iron (III) (chlorohemin) with Cr-phthalocyanine (CrPc) is the most effective for increasing water splitting activity, and the formation rates of H2 and O2 are 2.12 mmol g h−1 and 1.11 mmol g h−1, respectively. Energy conversion efficiency of this photocatalyst is estimated to be approximately 0.05%. From X-ray photoelectron spectroscopy measurement and cyclic voltammetry of organic dyes, it is suggested that the electronic state of the dye mixture is modified compared with that of a single dye. Energy transfer between mixing dyes is observed in the fluorescence spectra of dye-modified KTaO3 photocatalysts. Recombination of photoexited charge in KTaO3 is clearly suppressed by dye mixing, thus improvement of photocatalytic activity is attributed to the lengthening of excitation lifetime. This study reveals that mixing porphyrinoid dyes is an effective method for increasing water splitting activity of dye-modified KTaO3 photocatalysts. DEWEY : 621.47 ISSN : 0199-6231 En ligne : http://asmedl.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JSEEDO00013200 [...]