scispace - formally typeset
Search or ask a question
Topic

Oxygen

About: Oxygen is a research topic. Over the lifetime, 48149 publications have been published within this topic receiving 1113788 citations. The topic is also known as: O & Oxygen.


Papers
More filters
Journal ArticleDOI
TL;DR: In this article, the authors investigated the oxygen reduction reaction at the interface between a 50 μm radius platinum disk electrode and two solid polymer electrolyte membranes (Nafion® 117 and BAM® 407) over a range of temperatures (303 −343 K) and oxygen pressures (2 −5 atm absolute), at 100% relative humidity, using a solid-state electrochemical cell.

170 citations

Journal ArticleDOI
TL;DR: Evidence is presented of the effectiveness of bioremediation under mixed oxygen/nitrate conditions under some critical oxygen threshold, however high levels of oxygen inhibit denitrification.
Abstract: Bioremediation of aromatic hydrocarbons in groundwater and sediments is often limited by dissolved oxygen. Many aromatic hydrocarbons degrade very slowly or not at all under anaerobic conditions. Nitrate is a good alternative electron acceptor to oxygen, and denitrifying bacteria are commonly found in the subsurface and in association with contaminated aquifer materials. Providing both nitrate and microaerophilic levels of oxygen may result in oxidation of the stable benzene rings in aromatic contaminants and allow for the intermediates of this oxidation to degrade via denitrification. The effects of using mixed electron acceptors on biodegradation of subsurface contaminants is unclear. Below some critical oxygen threshold, aerobic biodegradation is inhibited, however high levels of oxygen inhibit denitrification. The mechanisms which regulate electron transfer to oxygen and nitrate are complex. This review: 1) describes the factors which may affect the utilization of oxygen and nitrate as dual electron acceptors during biodegradation; 2) summarizes the incidence of dual use of nitrate and oxygen (aerobic denitrification); and 3) presents evidence of the effectiveness of bioremediation under mixed oxygen/nitrate conditions.

170 citations

Journal ArticleDOI
TL;DR: In this article, the effect of morphology of α-MnO2 nanostructures on its catalytic activity for ozone decomposition was investigated, and it was found that the catalytic performance of the α-mnO2 is dependent on the amount of oxygen vacancies.

170 citations

Journal ArticleDOI
TL;DR: Li1-xNi1-yCoyO2-δ oxides have been synthesized for 0 ≤ x ≤ 1 and 0 ≤ y ≤ 1 by chemically extracting lithium at ambient temperature from LiNiNiO2 with an oxidizing agent NO2PF6 in acetonitrile medium.
Abstract: Li1-xNi1-yCoyO2-δ oxides have been synthesized for 0 ≤ x ≤ 1 and 0 ≤ y ≤ 1 by chemically extracting lithium at ambient temperature from LiNi1-yCoyO2 with an oxidizing agent NO2PF6 in acetonitrile medium. The samples have been characterized by X-ray diffraction, wet-chemical analyses to determine lithium and oxygen contents, and infrared spectroscopy. While the nickel-rich end members Ni1-yCoyO2-δ have the O3 structure similar to the initial LiNiO2, but with smaller lattice parameters, the cobalt-rich end members Ni1-yCoyO2-δ consist of a mixture of P3 and O1 phases that are formed from the initial O3 structure of LiCoO2 by a sliding of the oxide-ion layers. The nickel-rich phases Li1-xNi1-yCoyO2-δ have an oxygen content close to 2 with a negligible amount of oxygen vacancies, while the cobalt-rich phases have considerable amount of oxygen vacancies (δ = 0.33 in CoO2-δ). Fourier transform infrared spectroscopy indicates a semiconductor to metal transition in Li1-xCoO2-δ for (1 − x) < 0.77. On the other han...

170 citations

Journal ArticleDOI
TL;DR: In this paper, the adsorption and reactions of methanol, acetylene, water, and ethylene were investigated on clean and oxidized Au(110) surfaces by temperature-programmed reaction spectroscopy.
Abstract: The adsorption and reactions of methanol, acetylene, water, and ethylene were investigated on clean and oxidized Au(110) surfaces by temperature-programmed reaction spectroscopy. All of these molecules are only weakly and molecularly adsorbed on the clean Au(110) surface. Methanol, acetylene, and water, however, react with the oxidized surface. Methanol, activated by 0.25 monolayer of oxygen adatoms, reacts to form water, methyl formate, hydrogen, and carbon dioxide. A stable methoxy intermediate is identified in these reactions. Acetylene reacts to form water and carbon dioxide, and water is more strongly bonded to the Au(110) surface in the presence of oxygen adatoms. Ethylene is the only one of these molecules which does not react with oxygen adatoms on Au(110). This pattern of reactivity parallels that associated with the acidity of these molecules as measured in the gas phase which has been observed on Cu(110) and Ag(110) surfaces. These results complete the studies necessary to demonstrate the Broensted base character of oxygen adatoms on all of the group 1B metals.

170 citations


Network Information
Related Topics (5)
Electrolyte
124.6K papers, 2.3M citations
85% related
Carbon
129.8K papers, 2.7M citations
82% related
Hydrogen
132.2K papers, 2.5M citations
81% related
Oxide
213.4K papers, 3.6M citations
80% related
Aqueous solution
189.5K papers, 3.4M citations
78% related
Performance
Metrics
No. of papers in the topic in previous years
YearPapers
20233,516
20226,670
20211,229
20201,164
20191,190
20181,153