Enhanced Photoreduction Activity of Carbon Dioxide over Co3O4/CeO2Catalysts under Visible Light Irradiation

There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

Abstract

A series of new two semiconductor catalysts, Co ₃O ₄/CeO ₂, were prepared by glycine-nitrate combustion method for photocatalytic reduction of carbon dioxide to produce methanol and ethanol under visible light ( $λ > 400$ nm) irradiation. The catalysts were characterized by BET, UV-vis spectra, XRD, SEM, PL, and XPS and the results indicated that the catalyst with 5 wt.% of Co ₃O ₄has the highest yield among all kinds of tests with the methanol yield of 1.52 μmol·g ⁻¹·h ⁻¹and the ethanol yield of 4.75 μmol·g ⁻¹·h ⁻¹, which are about 2.34 and 1.71 times as large as those of CeO ₂. However, methanol and ethanol can hardly be detected for Co ₃O ₄under the same condition because of its too narrow band gap. The improvement of the photoreduction activity of Co ₃O ₄doped CeO ₂was caused by the separation of electron-hole pairs of Co ₃O ₄/CeO ₂and charge transfer between Co ₃O ₄and CeO ₂, mimicking the Z-scheme in photosynthesis.

Related collections

Most cited references 43

Record: found
Abstract: found
Article: not found

Reduced graphene oxide for catalytic oxidation of aqueous organic pollutants.

Hongqi Sun, Shizhen Liu, Guanliang Zhou … (2012)

We discovered that chemically reduced graphene oxide, with an I(D)/I(G) >1.4 (defective to graphite) can effectively activate peroxymonosulfate (PMS) to produce active sulfate radicals. The produced sulfate radicals (SO(4)(•-)) are powerful oxidizing species with a high oxidative potential (2.5-3.1 vs 2.7 V of hydroxyl radicals), and can effectively decompose various aqueous contaminants. Graphene demonstrated a higher activity than several carbon allotropes, such as activated carbon (AC), graphite powder (GP), graphene oxide (GO), and multiwall carbon nanotube (MWCNT). Kinetic study of graphene catalyzed activation of PMS was carried out. It was shown that graphene catalysis is superior to that on transition metal oxide (Co(3)O(4)) in degradation of phenol, 2,4-dichlorophenol (DCP) and a dye (methylene blue, MB) in water, therefore providing a novel strategy for environmental remediation.

0 comments Cited 150 times – based on 0 reviews      Review now

Bookmark

Record: found
Abstract: found
Article: not found

Efficient photocatalytic degradation of phenol over Co3O4/BiVO4 composite under visible light irradiation.

Mingce Long, Weimin Cai, Jun Cai … (2006)

Co3O4/BiVO4 composite photocatalyst with a p-n heterojunction semiconductor structure has been synthesized by the impregnation method. The physical and photophysical properties of the composite photocatalyst have been characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transimission electron microscopy (TEM), BET surface area, and UV-visible diffuse reflectance spectra. Co is present as p-type Co3O4 and disperses on the surface of n-type BiVO4 to constitute a heterojunction composite. The photocatalyst exhibits enhanced photocatalytic activity for phenol degradation under visible light irradiation. The highest efficiency is observed when calcined at 300 degrees C with 0.8 wt % cobalt content. On the basis of the calculated energy band positions and PL spectra, the mechanism of enhanced photocatalytic activity has been discussed.