The Influence of Illumination on the Flat Band Potential of the Contact TiO2/CH3CN(+ H2O)

Schumacher, R.; Teschner, D. M.; Heinzel, A.

doi:10.1002/bbpc.198200058

Cited by 14 publications

(11 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The values are in line with the values reported by Redmond and Fitzmaurice and our previous results which are determined from Mott–Schottky analysis . We note that our value of E fb in dry CH 3 CN (−2.10 V) is comparable to those obtained by Schumacher , and Fitzmaurice . These potentials are significantly more negative than those reported for CH 3 CN in other literature studies. ,, If we take this value as E fb of the hybrid, the endergonic electron injection from ZnP into dry TiO 2 particles would be much slower.…”

Section: Resultssupporting

confidence: 92%

Collisional Electron Transfer Route between Homogeneous Porphyrin Dye and Catalytic TiO₂/Re(I) Particles for CO₂ Reduction

Choi

Kim

Baeg

et al. 2020

ACS Appl. Energy Mater.

View full text Add to dashboard Cite

Dye detachment issue in the TiO 2 -mediated dye-sensitized photocatalytic system engenders an electron injection route based on collisional quenching between the detached solution-phase dye and dispersed n-type TiO 2 particles, in addition to the general fast electron injection pathway from dye chemisorbed on TiO 2 . For porphyrinsensitized hetero-binary hybrids prepared by mixing a solution-phase Zn porphyrin sensitizer (ZnP) and heterogeneous Re(I) molecular catalystimmobilized TiO 2 particles (TiO 2 /Re(I)), we found that without any dye immobilization on the TiO 2 surface, the dissolved porphyrin dye can effectively transport its excited-state electrons to the heterogeneous catalytic TiO 2 /Re(I) particles via a collisional electron transfer pathway, which is relatively unstudied and thus an interesting topic in the dye-sensitized semiconductor photocatalytic system. The better light-harvesting ability of porphyrin in solution and the TiO 2induced stabilization of the molecular Re(I) catalyst raised the photochemical CO 2 -to-CO conversion activity of the semiheterogeneous system (porphyrin + TiO 2 /Re(I) catalyst) above that of the homogeneous system (porphyrin + Re(I) catalyst) and the heterogeneous ternary hybrid (porphyrin/TiO 2 /Re(I) catalyst).

show abstract

Section: Resultssupporting

confidence: 92%

Collisional Electron Transfer Route between Homogeneous Porphyrin Dye and Catalytic TiO₂/Re(I) Particles for CO₂ Reduction

Choi

Kim

Baeg

et al. 2020

ACS Appl. Energy Mater.

View full text Add to dashboard Cite

show abstract

“…−2 V) and after illumination (ca. 0 V vs NHE) of E fb of TiO 2 for single crystals vary in +2 V, , and there is a difference between the E fb from the photocurrent (−0.6 V) and Mott−Schottky methods (<−1 V); this could be due to the photo-oxidation of the electrolyte or traces of water that modified the liquid/TiO 2 interface or relaxation phenomena caused by surface states or traps that affect the impedance measurements . Redmond and Fitzmaurice found that Li + could change the E fb from −1.8 V, without Li + , to −0.6 V vs NHE with Li + ≥ 0.01 M .…”

Section: Resultsmentioning

confidence: 99%

Photoelectrochemical Study of the Band Structure of Zn₂SnO₄ Prepared by the Hydrothermal Method

2009

View full text Add to dashboard Cite

It is fundamentally interesting to study the photoelectrochemical properties of complex oxides for applications in photovoltaics and photocatalysis. In this paper, we study the band gap (E g ) and energetics of the conduction band (CB) and valence band (VB) for films of zinc stannate (Zn 2 SnO 4 ) nanoparticles (ca. 25 nm) of the inverse-spinel structure prepared by the hydrothermal method. UV-vis spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), electrochemistry, and photoelectrochemistry were used to study the films. The fundamental E g for Zn 2 SnO 4 is proposed to be 3.6-3.7 eV with a directforbidden transition. The position of the CB was approximated from the flat band potential, E fb , measured by the photocurrent onset potential. In aqueous and nonaqueous solutions the E fb of n-Zn 2 SnO 4 was found to be more positive than TiO 2 anatase in the electrochemical scale. In aqueous solutions E fb of Zn 2 SnO 4 was found to follow a 59 mV/pH slope with E fb extrapolated at pH 0 of 0.08 V vs NHE. In acetonitrile solutions that simulate the electrolyte for dye-sensitized solar cells (DSCs) the E fb of Zn 2 SnO 4 was found to be strongly dependent on electrolyte composition and more positive than TiO 2 vs the I -/I 3 couple. The reverse trend observed for the open-circuit voltage in certain DSC electrolytes is explained in terms of the higher rates of electron-triiodide recombination of TiO 2 despite the lower position of the Zn 2 SnO 4 CB in the vacuum scale.

show abstract

“…In the present systems, we assumed that or is the main oxidizing species, as given by eq 7, where has a flat band potential for the valence band ( E VB ) of about +2.1 V vs NHE …”

Section: Resultsmentioning

confidence: 99%

Photocatalytic Oxidation Reactivity of Holes in the Sulfur- and Carbon-Doped TiO₂ Powders Studied by Time-Resolved Diffuse Reflectance Spectroscopy

et al. 2004

View full text Add to dashboard Cite

The photocatalytic oxidation reactivities of the photogenerated holes (h+) during ultraviolet or visible laser flash photolysis of pure anatase and sulfur- and carbon-doped TiO2 powders were investigated using time-resolved diffuse reflectance (TDR) spectroscopy. The one-electron oxidation processes of substrates such as methanol and 4-(methylthio)phenyl methanol (MTPM) by h+ at the TiO2 surface were examined. The TDR spectra and time traces observed for charge carriers and the MTPM radical cation (MTPM•+) revealed that the oxidation reactions of substrates by h+ generated during the 355-nm laser photolysis of TiO2 powders increased in the order of pure TiO2 > S-doped TiO2 > C-doped TiO2. On the other hand, no one-electron oxidation reactions of the substrates were observed during the 430-nm laser photolysis of the S- and C-doped TiO2 powders, although the charge carriers were sufficiently generated upon excitation. The effects of the trapping and detrapping processes of h+ at the doping sites on the oxidation reactions during the laser flash photolyses of the TiO2 powders are discussed.

show abstract

The Influence of Illumination on the Flat Band Potential of the Contact TiO₂/CH₃CN(+ H₂O)

Cited by 14 publications

References 19 publications

Collisional Electron Transfer Route between Homogeneous Porphyrin Dye and Catalytic TiO₂/Re(I) Particles for CO₂ Reduction

Collisional Electron Transfer Route between Homogeneous Porphyrin Dye and Catalytic TiO₂/Re(I) Particles for CO₂ Reduction

Photoelectrochemical Study of the Band Structure of Zn₂SnO₄ Prepared by the Hydrothermal Method

Photocatalytic Oxidation Reactivity of Holes in the Sulfur- and Carbon-Doped TiO₂ Powders Studied by Time-Resolved Diffuse Reflectance Spectroscopy

Contact Info

Product

Resources

About

The Influence of Illumination on the Flat Band Potential of the Contact TiO2/CH3CN(+ H2O)

Cited by 14 publications

References 19 publications

Collisional Electron Transfer Route between Homogeneous Porphyrin Dye and Catalytic TiO2/Re(I) Particles for CO2 Reduction

Collisional Electron Transfer Route between Homogeneous Porphyrin Dye and Catalytic TiO2/Re(I) Particles for CO2 Reduction

Photoelectrochemical Study of the Band Structure of Zn2SnO4 Prepared by the Hydrothermal Method

Photocatalytic Oxidation Reactivity of Holes in the Sulfur- and Carbon-Doped TiO2 Powders Studied by Time-Resolved Diffuse Reflectance Spectroscopy

Contact Info

Product

Resources

About

The Influence of Illumination on the Flat Band Potential of the Contact TiO₂/CH₃CN(+ H₂O)

Collisional Electron Transfer Route between Homogeneous Porphyrin Dye and Catalytic TiO₂/Re(I) Particles for CO₂ Reduction

Collisional Electron Transfer Route between Homogeneous Porphyrin Dye and Catalytic TiO₂/Re(I) Particles for CO₂ Reduction

Photoelectrochemical Study of the Band Structure of Zn₂SnO₄ Prepared by the Hydrothermal Method

Photocatalytic Oxidation Reactivity of Holes in the Sulfur- and Carbon-Doped TiO₂ Powders Studied by Time-Resolved Diffuse Reflectance Spectroscopy