Английская Википедия:Cerium(III) oxide
Cerium(III) oxide, also known as cerium oxide, cerium trioxide, cerium sesquioxide, cerous oxide or dicerium trioxide, is an oxide of the rare-earth metal cerium. It has chemical formula Шаблон:Chem2 and is gold-yellow in color.
Applications
Engine and exhaust catalysts
Cerium oxide is used as a catalytic converter for the minimisation of CO emissions in the exhaust gases from motor vehicles.
When there is a shortage of oxygen, cerium(IV) oxide is reduced by carbon monoxide to cerium(III) oxide:
When there is an oxygen surplus, the process is reversed and cerium(III) oxide is oxidized to cerium(IV) oxide:
Major automotive applications for cerium(III) oxide are as a catalytic converter for the oxidation of CO and [[NOx|Шаблон:Chem2]] emissions in the exhaust gases from motor vehicles,[1][2] and secondly, cerium oxide finds use as a fuel additive to diesel fuels, which results in increased fuel efficiency and decreased hydrocarbon derived particulate matter emissions,[3] however the health effects of the cerium oxide bearing engine exhaust is a point of study and dispute.[4][5][6]
Water splitting
The cerium(IV) oxide–cerium(III) oxide cycle or Шаблон:Chem2 cycle is a two step thermochemical water splitting process based on cerium(IV) oxide and cerium(III) oxide for hydrogen production.[7]
Photoluminescence
Cerium(III) oxide combined with tin(II) oxide (SnO) in ceramic form is used for illumination with UV light. It absorbs light with a wavelength of 320 nm and emits light with a wavelength of 412 nm.[8] This combination of cerium(III) oxide and tin(II) oxide is rare, and obtained only with difficulty on a laboratory scale.Шаблон:Citation needed
Production
Cerium(III) oxide is produced by the reduction of cerium(IV) oxide with hydrogen at approximately Шаблон:Convert. Samples produced in this way are only slowly air-oxidized back to the dioxide at room temperature.[9]
References
External links
Шаблон:Cerium compounds Шаблон:Oxides
- ↑ Bleiwas, D.I. (2013). Potential for Recovery of Cerium Contained in Automotive Catalytic Converters. Reston, Va.: U.S. Department of the Interior, U.S. Geological Survey.
- ↑ Шаблон:Cite web
- ↑ Шаблон:Cite web
- ↑ Шаблон:Cite web
- ↑ Шаблон:Cite journal
- ↑ Шаблон:Cite web
- ↑ Hydrogen production from solar thermochemical water splitting cycles Шаблон:Webarchive
- ↑ Шаблон:Cite journal
- ↑ Шаблон:Cite book
