Sensitization

elhamouz's picture

Dye-effect in TiO2 catalyzed contaminant photo-degradation: Sensitization vs. charge-transfer formalism

Journal Title, Volume, Page: 
Solid State Sciencesو Volume 9, Issue 1, Pages 9–15
Year of Publication: 
2007
Authors: 
H.S. Hilal
Department of Chemistry, An-Najah N. University, PO Box 7, University Street, Nablus, West Bank, Palestine
L.Z. Majjad
Department of Chemistry, An-Najah N. University, PO Box 7, University Street, Nablus, West Bank, Palestine
N. Zaatar
Department of Chemistry, An-Najah N. University, PO Box 7, University Street, Nablus, West Bank, Palestine
A. El-Hamouz
Department of Chemical Engineering, An-Najah N. University, PO Box 7, University Street, Nablus, West Bank, Palestine
Current Affiliation: 
Department of Chemical Engineering, An-Najah National University, Nablus, Palestine
Preferred Abstract (Original): 
Anatase TiO2 surfaces have been treated with 2,4,6-triphenylpyrilium hydrogen sulfate (TPPHS) dye to yield the modified TiO2/TPPHS surface. The modified TiO2/TPPHS surface was then supported onto activated carbon (AC) surfaces to yield a new class of catalytic system AC/TiO2/TPPHS. The catalytic activities of naked TiO2, TPPHS solution, TiO2/TPPHS and AC/TiO2/TPPHS systems were examined in photo-degradation of phenol and benzoic acid in water, using both UV and visible regions. All studied systems showed low catalytic activity when used in the visible region. In UV, the AC/TiO2/TPPHS showed highest activity, whereas the naked TiO2 and TPPHS solutions were the least active systems. The dye role, in enhancing activity of modified surfaces in UV degradation of contaminants, is understandable by a charge-transfer catalytic effect rather than a sensitizing effect. AC role is explainable by its ability to adsorb contaminant molecules and bringing them closer to catalytic sites.

Full Text

Nidal Zatar's picture

Dye-effect in TiO2 catalyzed contaminant photo-degradation: Sensitization vs. charge- transfer formalism

Journal Title, Volume, Page: 
Science Direct, Solide state science 9 (2007) 9-15.
Year of Publication: 
2007
Authors: 
N. Zatar
Department of Chemistry, An-Najah N. University, PO Box 7, University Street, Nablus, West Bank, Palestine
Current Affiliation: 
Department of Chemistry, An-Najah N. University, PO Box 7, University Street, Nablus, West Bank, Palestine
H.S. Hilal
Department of Chemistry, An-Najah N. University, PO Box 7, University Street, Nablus, West Bank, Palestine
L.Z. Majjad
Department of Chemistry, An-Najah N. University, PO Box 7, University Street, Nablus, West Bank, Palestine
A. El-Hamouz
Department of Chemical Engineering, An-Najah N. University, PO Box 7, University Street, Nablus, West Bank, Palestine
Preferred Abstract (Original): 

Anatase TiO2 surfaces have been treated with 2,4,6-triphenylpyrilium hydrogen sulfate (TPPHS) dye to yield the modified TiO2/TPPHS surface. The modified TiO2/TPPHS surface was then supported onto activated carbon (AC) surfaces to yield a new class of catalytic system AC/TiO2/TPPHS. The catalytic activities of naked TiO2, TPPHS solution, TiO2/TPPHS and AC/TiO2/TPPHS systems were examined in photo-degradation of phenol and benzoic acid in water, using both UV and visible regions. All studied systems showed low catalytic activity when used in the visible region. In UV, the AC/TiO2/TPPHS showed highest activity, whereas the naked TiO2 and TPPHS solutions were the least active systems. The dye role, in enhancing activity of modified surfaces in UV degradation of contaminants, is understandable by a charge-transfer catalytic effect rather than a sensitizing effect. AC role is explainable by its ability to adsorb contaminant molecules and bringing them closer to catalytic sites.

Full Text

iyad's picture

Cds-Sensitized Tio2 in Phenazopyridine Photo-Degradation: Catalyst Efficiency, Stability and Feasibility Assessment

Journal Title, Volume, Page: 
Journal of Hazardous Materials Volume 173, Issue 1-3, 15 January 2010, Pages 318-325
Year of Publication: 
2010
Authors: 
Iyad Saadeddin
Department of Chemistry, An-Najah N. University, PO Box 7, Nablus, Palestine
Current Affiliation: 
Department of Physics, An-Najah National University, Nablus, Palestine
Hikmat S. Hilal
Department of Chemistry, An-Najah N. University, PO Box 7, Nablus, Palestine
Ahed H. Zyoud
Department of Chemistry, An-Najah N. University, PO Box 7, Nablus, Palestine
Nidal Zaatar
Department of Chemistry, An-Najah N. University, PO Box 7, Nablus, Palestine
Cheknane Ali
Laboratoire d'Etude et Developpement des materiaux Dielectriques et Semiconducteurs, Université Amar Telidji de Laghouat, Laghouat, Algeria
DaeHoon Park
Institut de Chimie de la Matière Condensée de Bordeaux (ICMCB), 87 Avenue du Dr. A Schweitzer, 33608 Pessac, France
Guy Campet
Institut de Chimie de la Matière Condensée de Bordeaux (ICMCB), 87 Avenue du Dr. A Schweitzer, 33608 Pessac, France
Preferred Abstract (Original): 

Mineralization of phenazopyridine, 1, in water, under solar-simulator radiation was efficiently achieved using nanoparticle CdS-sensitized rutile TiO2, TiO2/CdS, 2, as photo-catalysts. Despite that, 2 showed two main drawbacks. Firstly, the system was difficult to recover by simple filtration, and demanded centrifugation. Secondly, the sensitizer CdS showed relatively high tendency to leach out hazardous Cd2+ ions under photo-degradation reaction conditions. In an attempt to solve out such difficulties, 2 was supported onto sand surface. The sand/TiO2/CdS system, 3, was easier to recover but showed slightly lower catalytic activity compared to 2. On the other hand, the support failed to prevent leaching of Cd2+. This indicates limited future applicability of CdS-sensitized TiO2 photo-catalyst systems, in solar-based water purification strategies, unless leaching out tendency is completely prevented.

Nidal Zatar's picture

Cds-Sensitized Tio2 in Phenazopyridine Photo-Degradation: Catalyst Efficiency, Stability and Feasibility Assessment

Journal Title, Volume, Page: 
Journal of Hazardous Materials Volume 173, Issue 1-3, 15 January 2010, Pages 318-325
Year of Publication: 
2010
Authors: 
Nidal Zaatar
Department of Chemistry, An-Najah N. University, PO Box 7, Nablus, West Bank, Palestine
Current Affiliation: 
Department of Chemistry, An-Najah N. University, PO Box 7, Nablus, West Bank, Palestine
Iyad Saadeddin
Department of Chemistry, An-Najah N. University, PO Box 7, Nablus, West Bank, Palestine
Cheknane Ali
Laboratoire d'Etude et Developpement des materiaux Dielectriques et Semiconducteurs, Université Amar Telidji de Laghouat, Laghouat, Algeria
DaeHoon Park
Institut de Chimie de la Matière Condensée de Bordeaux (ICMCB), 87 Avenue du Dr. A Schweitzer, 33608 Pessac, France
Guy Campet
Institut de Chimie de la Matière Condensée de Bordeaux (ICMCB), 87 Avenue du Dr. A Schweitzer, 33608 Pessac, France
Hikmat S. Hilal
Department of Chemistry, An-Najah N. University, PO Box 7, Nablus, West Bank, Palestine
Preferred Abstract (Original): 

Mineralization of phenazopyridine, 1, in water, under solar-simulator radiation was efficiently achieved using nanoparticle CdS-sensitized rutile TiO2, TiO2/CdS, 2, as photo-catalysts. Despite that, 2 showed two main drawbacks. Firstly, the system was difficult to recover by simple filtration, and demanded centrifugation. Secondly, the sensitizer CdS showed relatively high tendency to leach out hazardous Cd2+ ions under photo-degradation reaction conditions. In an attempt to solve out such difficulties, 2 was supported onto sand surface. The sand/TiO2/CdS system, 3, was easier to recover but showed slightly lower catalytic activity compared to 2. On the other hand, the support failed to prevent leaching of Cd2+. This indicates limited future applicability of CdS-sensitized TiO2 photo-catalyst systems, in solar-based water purification strategies, unless leaching out tendency is completely prevented.

Hikmat S. Hilal's picture

Cds-Sensitized Tio2 In Phenazopyridine Photo-Degradation: Catalyst Efficiency, Stability And Feasibility Assessment

Journal Title, Volume, Page: 
Journal of Hazardous Materials Volume 173, Issues 1-3,Pages 318-325
Year of Publication: 
2010
Authors: 
Hikmat S. Hilal
Department of Chemistry, An-Najah N. University, PO Box 7, Nablus, West Bank, Palestine
Current Affiliation: 
Department of Chemistry, An-Najah N. University, PO Box 7, Nablus, West Bank, Palestine
Ahed H. Zyoud
Department of Chemistry, An-Najah N. University, PO Box 7, Nablus, West Bank, Palestine
Nidal Zaatar
Department of Chemistry, An-Najah N. University, PO Box 7, Nablus, West Bank, Palestine
Cheknane Ali
Laboratoire d’Etude et Développement des matériaux Diélectriques et Semiconducteurs, Université Amar Telidji de Laghouat, Laghouat, Algeria
Iyad Saadeddin
Department of Chemistry, An-Najah N. University, PO Box 7, Nablus, West Bank, Palestine
DaeHoon park
Institut de Chimie de la Matière Condensée de Bordeaux (ICMCB), 87 Avenue du Dr. A Schweitzer, 33608 Pessac, France
Guy Campet
Institut de Chimie de la Matière Condensée de Bordeaux (ICMCB), 87 Avenue du Dr. A Schweitzer, 33608 Pessac, France
Preferred Abstract (Original): 
Mineralization of phenazopyridine, 1, in water, under solar-simulator radiation was efficiently achieved using nanoparticle CdS-sensitized rutile TiO2, TiO2/CdS, 2, as photo-catalysts. Despite that, 2 showed two main drawbacks. Firstly, the system was difficult to recover by simple filtration, and demanded centrifugation. Secondly, the sensitizer CdS showed relatively high tendency to leach out hazardous Cd2+ ions under photo-degradation reaction conditions. In an attempt to solve out such difficulties, 2 was supported onto sand surface. The sand/TiO2/CdS system, 3, was easier to recover but showed slightly lower catalytic activity compared to 2. On the other hand, the support failed to prevent leaching of Cd2+. This indicates limited future applicability of CdS-sensitized TiO2 photo-catalyst systems, in solar-based water purification strategies, unless leaching out tendency is completely prevented.
ahedzyoud's picture

Cds-Sensitized TiO2 in Phenazopyridine Photo-Degradation: Catalyst Efficiency, Stability and Feasibility Assessment

Journal Title, Volume, Page: 
Journal of Hazardous Materials, Volume:173, Issue 1-3, Pages:318-325
Year of Publication: 
2010
Authors: 
Ahed H. Zyoud
Department of Chemistry, An-Najah National University, Nablus, Palestine
Current Affiliation: 
Department of Chemistry, An-Najah National University, Nablus, Palestine
Nidal Zaatar
Department of Chemistry, An-Najah National University, Nablus, Palestine
Iyad Saadeddin
Department of Chemistry, An-Najah National University, Nablus, Palestine
Cheknane Ali
Laboratoire d’Etude et Développement des matériaux Diélectriques et Semiconducteurs, Université Amar Telidji de Laghouat, Laghouat, Algeria
DaeHoon Park
Institut de Chimie de la Matière Condensée de Bordeaux (ICMCB), 87 Avenue du Dr. A Schweitzer, 33608 Pessac, France
Guy Campet
Institut de Chimie de la Matière Condensée de Bordeaux (ICMCB), 87 Avenue du Dr. A Schweitzer, 33608 Pessac, France
Hikmat S. Hilal
Department of Chemistry, An-Najah National University, Nablus, Palestine
Preferred Abstract (Original): 

Mineralization of phenazopyridine, 1, in water, under solar-simulator radiation was efficiently achieved using nanoparticle CdS-sensitized rutile TiO2, TiO2/CdS, 2, as photo-catalysts. Despite that, 2 showed two main drawbacks. Firstly, the system was difficult to recover by simple filtration, and demanded centrifugation. Secondly, the sensitizer CdS showed relatively high tendency to leach out hazardous Cd2+ ions under photo-degradation reaction conditions. In an attempt to solve out such difficulties, 2 was supported onto sand surface. The sand/TiO2/CdS system, 3, was easier to recover but showed slightly lower catalytic activity compared to 2. On the other hand, the support failed to prevent leaching of Cd2+. This indicates limited future applicability of CdS-sensitized TiO2 photo-catalyst systems, in solar-based water purification strategies, unless leaching out tendency is completely prevented.

Hikmat S. Hilal's picture

Silica-Supported Cds-Sensitized Tio2 Particles in Photo-Degradation of Phenazopyridine: Assessment of Efficiency, Stability and Recovery

Journal Title, Volume, Page: 
IWAM, RAK-CAM, Ras Al-Khayma Center for Advanced materials
Year of Publication: 
2010
Authors: 
Hikmat S. Hilal
Department Of Chemistry, An-Najah N. University, Nablus, PO Box 7, West Bank, Palestine
Current Affiliation: 
Department Of Chemistry, An-Najah N. University, Nablus, PO Box 7, West Bank, Palestine
Ghazi Nour
Ahed Zyoud
Preferred Abstract (Original): 
Mineralization of phenazopyridine, 1, in water, under solar-simulator radiation was efficiently achieved using nanoparticle CdS-sensitized rutile TiO2 , TiO2 /CdS,  2,  as  photo-catalysts. Despite that, 2  showed two main drawbacks. Firstly, the system was difficult to recover by  simple filtration, and demanded centrifugation. Secondly, the sensitizer CdS showed relatively high tendency to leach out hazardous Cd2+ ions under photo-degradation reaction conditions. In  an attempt to solve out such difficulties, 2  was supported onto sand surface. The  sand/TiO2 /CdS  system, 3, was easier to recover but showed slightly lower catalytic activity compared to 2. On the other hand, the support failed to prevent leaching of Cd2+ . This  indicates limited future applicability of CdS-sensitized TiO2  photo-catalyst systems, in solar-based water purification strategies, unless leaching out tendency is completely prevented.
Hikmat S. Hilal's picture

Dye-Effect in Tio2 Catalyzed Contaminant Photodegradation: Sensitization Vs. Charge-Transfer Formalism

Journal Title, Volume, Page: 
Solid State Sciences Volume: 9, Issue:1, January 2007, Pages: 9-15
Year of Publication: 
2007
Authors: 
H.S. Hilal
Department of Chemistry, An-Najah N. University, PO Box 7, University Street, Nablus, West Bank, Palestine
Current Affiliation: 
Department Of Chemistry, An-Najah N. University, Nablus, PO Box 7, West Bank, Palestine
L.Z. Majjad
N. Zaatar
Department Of Chemistry, An-Najah N. University, Nablus, PO Box 7, West Bank, Palestine
A. El-Hamouz
Department Of Chemical Engineering, An-Najah N. University, PO Box 7, University Street, Nablus, West Bank, Palestine
Preferred Abstract (Original): 

Anatase TiO2 surfaces have been treated with 2,4,6-triphenylpyrilium hydrogen sulfate (TPPHS) dye to yield the modified TiO2/TPPHS surface. The modified TiO2/TPPHS surface was then supported onto activated carbon (AC) surfaces to yield a new class of catalytic system AC/TiO2/TPPHS. The catalytic activities of naked TiO2, TPPHS solution, TiO2/TPPHS and AC/TiO2/TPPHS systems were examined in photo-degradation of phenol and benzoic acid in water, using both UV and visible regions. All studied systems showed low catalytic activity when used in the visible region. In UV, the AC/TiO2/TPPHS showed highest activity, whereas the naked TiO2 and TPPHS solutions were the least active systems. The dye role, in enhancing activity of modified surfaces in UV degradation of contaminants, is understandable by a charge-transfer catalytic effect rather than a sensitizing effect. AC role is explainable by its ability to adsorb contaminant molecules and bringing them closer to catalytic sites.

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