Search results for "photocatalysi"
showing 10 items of 626 documents
Solid State Fluorination on the Minute Scale: Synthesis of WO 3− x F x with Photocatalytic Activity
2020
Combination of ozonation and photocatalysis for purification of aqueous effluents containing formic acid as probe pollutant and bromide ion
2014
The treatment by advanced oxidation processes (AOPs) of waters contaminated by organic pollutants and containing also innocuous bromide ions may generate bromate ions as a co-product. In the present work heterogeneous photocatalysis and ozonation have individually been applied and in combination (integrated process) to degrade the organic compounds in water containing also bromide anions. The results show that: i) the sole photocatalysis does not produce bromate ions and in the case of its presence, it is able to reduce bromate to innocuous bromide ions; ii) the integration of photocatalysis and ozonation synergistically enhances the oxidation capabilities; and iii) in the integrated proces…
High Activity of Brookite TiO2 Nanopowders in the Photocatalytic Abatement of Ammonia in Water
2014
A Solar Photothermocatalytic approach for the CO2 conversion: Investigation of different synergisms on CoO-CuO/Brookite TiO2-CeO2 catalysts
2022
Abstract The photoactive features of the least common polymorph of TiO2, i.e. brookite, were combined with the thermocatalytic redox ones of cerium oxide, focusing on the effects of the addition of small amounts of Co-Cu oxides for the solar CO2 conversion. By considering the characterization data, a surface segregation of the hosted metal oxides on the TiO2-CeO2 composite was evidenced, and their presence increased the amount of oxygen vacancies and improved the charge carriers separation. The bimetallic oxides-based sample was the most performing one in the photocatalytic carbon dioxide reduction at room temperature. The formation of carbon monoxide and methane was 5 and 0.5 μmol g−1h−1, …
2-propanol formation by propene hydration: Catalytic and catalytic photo- assisted reaction using H3PW12O40 supported on TiO2 and SiO2.
2012
Comparison between catalytic and catalytic photo-assisted propene hydration by using supported polyoxometalate.
2012
A study on the catalytic perfomances of H3PW12O40 supported on TiO2 and SiO2 for propene hydration in the presence and in the absence of UV light
2012
Photocatalytic CO 2 Valorization by Using Ti O2 , ZrO2 and Graphitic Based Semiconductors
2018
In this century, a broad scientific interest has been devoted to fulfill sustainable industrial processes and climatic change remediation. In this prospective, various green technologies have been studied to valorize CO 2• The aim of this research is the CO 2 reduction in presence of water by using the photocatalytic technology with nanomaterials as the photocatalysts. The present work overviews the main outcomes obtained by using graphitic and oxide based photocatalysts both in gas/solid and liquid/solid batch reactors under simulated solar light. In all gas/solid regime tests the major products detected were methane, carbon monoxide, and acetaldehyde.
Photoreduction of carbon dioxide to formic acid in aqueous suspension: a comparison between phthalocyanine/TiO2 and porphyrin/TiO2 catalysed processes
2014
Composite materials prepared by loading polycrystalline TiO2 powders with lipophilic highly branched Cu(II)- and metal-free phthalocyanines or porphyrins, which have been used in the past as photocatalysts for photodegradative processes, have been successfully tested for the efficient photoreduction of carbon dioxide in aqueous suspension affording significant amounts of formic acid. The results indicated that the presence of the sensitizers is beneficial for the photoactivity, confirming the important role of Cu(II) co-ordinated in the middle of the macrocycles. A comparison between Cu(II) phthalocyanines and Cu(II) porphyrins indicated that the Cu(II)- phthalocyanine sensitizer was more e…
Highly Efficient Electron Transfer in a Carbon Dot–Polyoxometalate Nanohybrid
2020
Using solar radiation to fuel catalytic processes is often regarded as the solution to our energy needs. However, developing effective photocatalysts that are active under visible light has proven to be difficult, often due to the toxicity, instability, and high cost of suitable catalysts. We engineered a novel photoactive nanomaterial obtained by the spontaneous electrostatic coupling of carbon nanodots with [P2W18O62]6-, a molecular catalyst belonging to the class of polyoxometalates. While the former are used as photosensitizers, the latter was chosen for its ability to catalyze reductive reactions such as dye decomposition and water splitting. We find the electron transfer within the na…