A potential gradient along the layer-by-layer architecture for electron transfer rectification

AbstractHydrogenation of benzoic acid (BA) to cyclohexanecarboxylic acid (CCA) has important industrial and academic significance, however, the electron deficient aromatic ring and catalyst poisoning by carboxyl groups make BA hydrogenation a challenging transformation. Herein, we report that Pt/TiO2 is very effective for BA hydrogenation with, to our knowledge, a record TOF of 4490 h−1 at 80 °C and 50 bar H2, one order higher than previously reported results. Pt/TiO2 catalysts with electron-deficient and electron-enriched Pt sites are obtained by modifying the electron transfer direction between Pt and TiO2. Electron-deficient Pt sites interact with BA more strongly than electron-rich Pt sites, helping the dissociated H of the carboxyl group to participate in BA hydrogenation, thus enhancing its activity. The wide substrate scope, including bi- and tri-benzoic acids, further demonstrates the high efficiency of Pt/TiO2 for hydrogenation of BA derivatives.

Download Full-text

Control of electron transfer by the electrochemical potential gradient in cytochrome-c oxidase reconstituted into phospholipid vesicles.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(19)39396-2 ◽

1990 ◽

Vol 265 (10) ◽

pp. 5554-5560

Author(s):

P Sarti ◽

F Malatesta ◽

G Antonini ◽

B Vallone ◽

M Brunori

Keyword(s):

Electron Transfer ◽

Cytochrome C ◽

Cytochrome C Oxidase ◽

Potential Gradient ◽

Electrochemical Potential ◽

Phospholipid Vesicles

Download Full-text

Excess Electron Transfer Driven DNA Does Not Depend on the Transfer Direction

Angewandte Chemie ◽

10.1002/ange.200490053 ◽

2004 ◽

Vol 116 (18) ◽

pp. 2373-2373

Author(s):

Clemens Haas ◽

Katja Kräling ◽

Michaela Cichon ◽

Nicole Rahe ◽

Thomas Carell

Keyword(s):

Electron Transfer ◽

Excess Electron ◽

Transfer Direction

Download Full-text

Anatomy of a Natural Sunlight Driven CdS/CoTiO3/ZnO Ternary Photocatalyst for Efficient Optical Properties and Removal of Reactive Orange 30

Research Journal of Chemistry and Environment ◽

10.25303/258rjce100109 ◽

2021 ◽

Vol 25 (8) ◽

pp. 100-109

Author(s):

G. Divya ◽

D. Sakthi ◽

A. Priyadharsan ◽

S. Boobas ◽

S. Sivakumar

Keyword(s):

Electron Transfer ◽

Photocatalytic Activity ◽

Potential Gradient ◽

Spatial Separation ◽

Morphological Properties ◽

Photoexcited Electron ◽

Visible Absorption ◽

Potential Applications ◽

The Difference ◽

Reactive Orange

ZnO as a promising photocatalyst has gained much attention for the removal of organic pollutants from water. However, the main drawbacks of the relatively low photocatalytic activity and high recombination rate of photoexcited electron-hole pairs restrict its potential applications. Promoting the spatial separation of photoexcited charge carriers is of paramount significance for photocatalysis because the difference in the band positions makes the potential gradient at the composite boundary. In this work, binary CdS/ZnO and CoTiO3/ZnO are first prepared by dispersion method and then decorated with ZnO particles to construct CdS/CoTiO3/ZnO ternary composites. For this reason, the CdS/CoTiO3/ZnO ternary composites was effectively designed and analyzed for the crystalline structure, light absorption, photoexcitation behavior and surface morphological properties by X-ray diffraction, diffuse reflectance UV/visible absorption spectroscopy, photoluminescence spectroscopy and scanning electron micrograph respectively. The photocatalytic activity was examined by degradation of the dye solution spectrophotometrically. The results of photocatalytic degradation indicated that the CdS/CoTiO3/ZnO ternary composites are much higher than those of bare CdS, CoTiO3, ZnO and any binary composites such as CoTiO3/ZnO and ZnO/CdS. The enhanced activity could be attributed to the drop electron transfer from CdS to ZnO to CoTiO3 through the interfacial potential gradient in the ternary hybrid conduction bands. The enhanced electron transfer of CdS/CoTiO3/ZnO ternary composites was also applicable to degrade other reactive dyes.

Download Full-text