TY - JOUR

T1 - Studies on the adsorption and photocatalytic degradation of an EuIII(TTFA)3(MePhTerpy) complex on the TiO2 surface

AU - Melchers, S.

AU - Alsalka, Y.

AU - Schneider, J.

AU - Bahnemann, D.W.

N1 - Funding information: This work was funded by the German Federal Ministry of Education and Research (contract no. 13N13350, PureBau – Untersuchung von Werkstoffsystemen für photokatalytisch hocheffiziente Baustoffe- Teilvorhaben: Oberflächenchemie der Photokatalysatoren und der Werkstoffe). Furthermore, Y. Alsalka gratefully acknowledges the financial support from the DAAD (Deutscher Akademischer Austauschdienst) . Additionally, we thank KRONOS ® for providing the TiO 2 materials and Dr. Johannes from the Technische Universität Braunschweig for the synthesis of the dye. This work was funded by the German Federal Ministry of Education and Research (contract no. 13N13350, PureBau – Untersuchung von Werkstoffsystemen für photokatalytisch hocheffiziente Baustoffe- Teilvorhaben: Oberflächenchemie der Photokatalysatoren und der Werkstoffe). Furthermore, Y. Alsalka gratefully acknowledges the financial support from the DAAD (Deutscher Akademischer Austauschdienst). Additionally, we thank KRONOS® for providing the TiO

PY - 2018/9/1

Y1 - 2018/9/1

N2 - The luminescent dye Europium III(thenoyltrifluoroacetone)(4′-(4-methylphenyl)-2,2′:6′,2′′-terpyridine) (Eu III(TTFA) 3(MePhTerpy)) has been proposed as a probe molecule for a fast photocatalytic test of TiO 2-materials. For an industrial application of this test method the underlying photocatalytic reaction mechanism and the degradation products of the dye need to be known. Hence, in this study the adsorption and the photocatalytic degradation of the luminescent dye on the TiO 2 surface were investigated by means of ATR-FTIR spectroscopy and GC/MS analysis. The dye is adsorbed by the thenoyltrifluoroacetone (TTFA) ligand on the TiO 2 surface as evinced by the respective ATR-FTIR spectra. It is assumed that TTFA and TiO 2 form hydrogen bonds. Upon UV illumination the ATR-FTIR spectra reveal a degradation of the TTFA ligand forming trifluoroacetic acid (TFAA) and 2-thiophenecarboxylic acid (TCA). GC/MS analysis confirms the ATR-FTIR results because TCA and TFAA are also detected here. Additionally, 2-thiophenecarboxaldehyde is observed, which is proposed to be an intermediate that is further oxidized to TCA.

AB - The luminescent dye Europium III(thenoyltrifluoroacetone)(4′-(4-methylphenyl)-2,2′:6′,2′′-terpyridine) (Eu III(TTFA) 3(MePhTerpy)) has been proposed as a probe molecule for a fast photocatalytic test of TiO 2-materials. For an industrial application of this test method the underlying photocatalytic reaction mechanism and the degradation products of the dye need to be known. Hence, in this study the adsorption and the photocatalytic degradation of the luminescent dye on the TiO 2 surface were investigated by means of ATR-FTIR spectroscopy and GC/MS analysis. The dye is adsorbed by the thenoyltrifluoroacetone (TTFA) ligand on the TiO 2 surface as evinced by the respective ATR-FTIR spectra. It is assumed that TTFA and TiO 2 form hydrogen bonds. Upon UV illumination the ATR-FTIR spectra reveal a degradation of the TTFA ligand forming trifluoroacetic acid (TFAA) and 2-thiophenecarboxylic acid (TCA). GC/MS analysis confirms the ATR-FTIR results because TCA and TFAA are also detected here. Additionally, 2-thiophenecarboxaldehyde is observed, which is proposed to be an intermediate that is further oxidized to TCA.

KW - Degradation

KW - Dye

KW - Europium complex

KW - Luminescence

KW - Photocatalysis

KW - TiO

UR - http://www.scopus.com/inward/record.url?scp=85048528503&partnerID=8YFLogxK

U2 - 10.1016/j.jphotochem.2018.06.016

DO - 10.1016/j.jphotochem.2018.06.016

M3 - Article

VL - 364

SP - 303

EP - 308

JO - Journal of Photochemistry and Photobiology A: Chemistry

JF - Journal of Photochemistry and Photobiology A: Chemistry

SN - 1010-6030

ER -