Publications related to Oxygen cycle

Operando identification of a side-on nickel superoxide intermediate and the mechanism of oxygen evolution on nickel oxyhydroxide

The oxygen evolution reaction (OER) is a key electrochemical reac-tion relevant to energy storage. Ni-containing bimetallic oxyhydrox-ides are among the most active OER catalysts in alkaline medium, but the mechanism of OER on pure Ni oxyhydroxide remains ...

ELSEVIER2023

Genomic insights into the coupling of a Chlorella-like microeukaryote and sulfur bacteria in the chemocline of permanently stratified Lake Cadagno

Christel Sybille Hassler

Meromictic Lake Cadagno is a permanently stratified system with a persistent microbial bloom within the oxic-anoxic boundary called the chemocline. The association between oxygenic and anoxygenic photosynthesis within the chemocline has been known for at l ...

SPRINGERNATURE2023

Near-bed stratification controls bottom hypoxia in ice-covered alpine lakes

Damien Bouffard, Camille Roland Marie Minaudo, Tomy Doda, Hugo Nicolás Ulloa Sánchez, Hannah Elisa Chmiel, Janine Rüegg, Nicolas Thomas Georges Escoffier, Pascal Perolo

In ice-covered lakes, near-bottom oxygen concentration decreases for most of the wintertime, sometimes down to the point that bottom waters become hypoxic. Studies insofar have reached divergent conclusions on whether climate change limits or reinforces th ...

American Society of Limnology and Oceanography2023

Evidence that Pacific tuna mercury levels are driven by marine methylmercury production and anthropogenic inputs

Hélène Paule Angot

Pacific Ocean tuna is among the most-consumed seafood products but contains relatively high levels of the neurotoxin methylmercury. Limited observations suggest tuna mercury levels vary in space and time, yet the drivers are not well understood. Here, we m ...

National Academy of Sciences2022

Monomeric Fe Species in Square Planar Geometry Active for Low Temperature NH3-SCR of NO

Oliver Kröcher, Davide Ferri

Monomeric Fe species in zeolites are considered to be the active sites for the low temperature activity toward ammonia-assisted selective catalytic reduction of nitrogen oxides (NH3-SCR) in exhaust gases. Herein, we report on a preparation method to synthe ...

AMER CHEMICAL SOC2022

Model-based scale-up of a continuously operated consolidated bioprocess based on a microbial consortium for the production of ethanol

David Beat Dempfle

This work demonstrated that consolidated bioprocessing is a promising concept for conversion of lignocellulose to ethanol at industrial scale. CBP offers great cost saving potential, is feasible to be operated continuously and may be scaled up due to exten ...

EPFL2022

Role of OH Intermediates during the Au Oxide Electro-Reduction at Low pH Elucidated by Electrochemical Surface-Enhanced Raman Spectroscopy and Implicit Solvent Density Functional Theory

Nicola Marzari, Francesco Nattino

Molecular understanding of the electrochemical oxidation of metals and the electro-reduction of metal oxides is of pivotal importance for the rational design of catalyst-based devices where metal(oxide) electrodes play a crucial role. Operando monitoring a ...

AMER CHEMICAL SOC2020

Print-Light-Synthesis of Ni and NiFe-nanoscale catalysts for oxygen evolution

Hubert Girault, Emad Oveisi, Mounir Driss Mensi, Andreas Stephan Lesch, Victor Costa Bassetto

By hyphenating inkjet printing and flash light irradiation, Ni- and NiFe-nano-electrocatalysts of diameters below 2.5 nm with ultralow loadings below 2 µg·cm–2 are synthesized. To achieve this, nanoliter ink volumes containing Ni and Fe chlorides as cataly ...

2019

Reaction pathway of oxygen evolution on Pt(111) revealed through constant Fermi level molecular dynamics

Alfredo Pasquarello, Assil Bouzid, Patrick Gono

The pathway of the oxygen evolution reaction at the Pt(111)/water interface is disclosed through constant Fermi level molecular dynamics. Upon the application of a positive bias potential H2Oads and OHads adsorbates are found to arrange in a hexagonal latt ...

2019

IrOOH nanosheets as acid stable electrocatalysts for the oxygen evolution reaction

Filip Mateusz Podjaski

In solids, heterogeneous catalysis is inherently bound to reactions on the surface. Yet, atomically efficient preparation of specific surfaces and the characterization of their properties are impeding its applications towards a clean energy future. Here, w ...

Royal Society of Chemistry2018

Amorphous Cobalt Vanadium Oxide as a Highly Active Electrocatalyst for Oxygen Evolution

Xile Hu, Laurent Liardet

The water-splitting reaction provides a promising mechanism to store renewable energies in the form of hydrogen fuel. The oxidation half-reaction, the oxygen evolution reaction (OER), is a complex four-electron process that constitutes an efficiency bottle ...

2018

Sequestered Chloroplasts In The Benthic Foraminifer Haynesina Germanica: Cellular Organization, Oxygen Fluxes And Potential Ecological Implications

Charlotte Madeleine Nicole Lekieffre, Emmanuelle Geslin

Haynesina germanica is a coastal benthic foraminifer known to sequester chloroplasts from benthic pennate diatoms. This study investigates its cellular organization, as well as the oxygen consumption and production rates under dark and light conditions. Th ...

2017

Unraveling Thermodynamics, Stability, and Oxygen Evolution Activity of Strontium Ruthenium Perovskite Oxide

Nicola Marzari, Ivano Eligio Castelli, Xi Cheng

Extensive investigations in understanding the functional mechanisms of metal oxides behind oxygen evolution have been carried out since an electrolyzer has demonstrated promising possibilities as a device to produce hydrogen for electrochemical energy conv ...

Amer Chemical Soc2017

A Spotlight on the Compatibility between XFEL and Ab Initio Structures of the Oxygen Evolving Complex in Photosystem II

Daniele Narzi, Leonardo Guidoni

The Mn4CaO5 cluster of photosystem II promotes a crucial step in the oxygenic photosynthesis, namely, the water-splitting reaction. The structure of such cluster in the S-1 state of the Kok-Joliot's cycle has been recently resolved by femtosecond X-ray fre ...

Wiley-V C H Verlag Gmbh2017

Scaling oxygen microprofiles at the sediment interface of deep stratified waters

Alfred Johny Wüest, Damien Bouffard, Robert Vincent Schwefel, Miki Hondzo

Dissolved oxygen microprofiles at the sediment-water interface of Lake Geneva were measured concurrently with velocities 0.25 to 2m above the sediment. The measurements and scaling analyses indicate dissolved oxygen fluctuations and turbulent fluxes in exc ...

American Geophysical Union2017

Oxygen depletion in stratified lakes - why shallow and deep lakes react differently

Alfred Johny Wüest, Robert Vincent Schwefel

Oxygen is the most important element in natural waters for any higher aquatic life, such as fish. As with humans, almost all members of aquatic ecosystems need oxygen to breathe. Building on this, treatment of drinking water is easier for oxic than for ano ...

2016

A nickel iron diselenide-derived efficient oxygen-evolution catalyst

Xile Hu, Fang Song, Xiang Xu

Efficient oxygen-evolution reaction catalysts are required for the cost-effective generation of solar fuels. Metal selenides have been reported as promising oxygen-evolution catalysts; however, their active forms are yet to be elucidated. Here we show that ...

Nature Publishing Group2016

Efficient Water Splitting Catalyzed by Cobalt Phosphide-Based Nanoneedle Arrays Supported on Carbon Cloth

Xile Hu, Peng Wang, Fang Song

Efficient and low-cost electrocatalysts for water splitting are essential for solar fuel production. Herein, we report that nanoarrays of CoP supported on carbon cloth are an efficient bifunctional catalyst for overall water splitting. The catalyst exhibit ...

Wiley-VCH Verlag Berlin2016

Investigation of 2R-Cell Degradation under Thermal Cycling and RedOx Cycling Conditions by Electrochemical Impedance Spectroscopy

Jan Van Herle, Stefan Diethelm, Vaibhav Singh

A 2R-cell with a 10 cm2 active area LSCF cathode on a CGO buffer layer was tested at 780°C under thermal and RedOx cycling conditions; 20 thermal cycles were performed between 780°C and 100°C, using 200°C/h heating ramps and natural cooling, followed by 20 ...

2015

Optimizing turbine withdrawal from a tropical reservoir for improved water quality in downstream wetlands

Alfred Johny Wüest, Bernhard Wehrli

Large reservoirs in the tropics act as efficient nutrient traps and often develop hypoxic conditions in the hypolimnion. Both effects may have severe implications for aquatic ecosystems, such as limited primary production in downstream riparian agriculture ...

American Geophysical Union2013