Publications associées à Nodule polymétallique

Microstructure - Electrochemical Surface Reactivity Relationship of Electrochemically Grown Manganese Oxides Films

This Thesis provides a comprehensive and correlative investigation of the microstructure, chemical state, and electrochemical reactivity of manganese oxide (MnOx) films, aiming to gain a deeper understanding of the deposition and dissolution mechanism of M ...

EPFL2024

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

Xile Hu, Lichen Bai, Seunghwa Lee

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

Diffusion timescale conundrum in contact metamorphism: Oxygen isotope and trace element profiles in dolomite

Anders Meibom, Stéphane Laurent Escrig, Lukas Baumgartner, Florence Bégué

Successful application of diffusion chronometry is based on detailed knowledge of diffusion parameters obtained from laboratory experiments, which also need to be upscaled to be applied to natural samples. While generally applicable, several examples of di ...

PERGAMON-ELSEVIER SCIENCE LTD2023

First paleoproteome study of fossil fish otoliths and the pristine preservation of the biomineral crystal host

Anders Meibom, Jaroslaw Hubert Stolarski, Jinming Guo

Otoliths are calcium carbonate components of the stato-acoustical organ responsible for hearing and maintenance of the body balance in teleost fish. During their formation, control over, e.g., morphology and carbonate polymorph is influenced by complex ins ...

Nature Portfolio2023

An innovative autonomous robotic system for on-site detection of heavy metal pollution plumes in surface water

Bhawna Nagar, Alexander Haider, Qiuyue Yang

Smart monitoring has been studied and developed in recent years to create faster, cheaper, and more user-friendly on-site methods. The present study describes an innovative technology for investigative monitoring of heavy metal pollution (Cu and Pb) in sur ...

SPRINGER2022

Tailoring the redox-active transition metal content to enhance cycling stability in cation-disordered rock-salt oxides

Corsin Battaglia, Chunyang Zhang, Yong Yang, Yining Li

Lithium-excess cation-disordered rock-salt oxides (DRXs) are investigated intensively as cathode materials for future lithium-ion batteries combining cationic and anionic redox reactions. However, the lattice oxygen redox can cause severe oxygen release re ...

ELSEVIER2021

Permanganate Reduction by Hydrogen Peroxide: Formation of Reactive Manganese Species and Superoxide and Enhanced Micropollutant Abatement

Urs von Gunten, Ke Xu

Permanganate (MnO4-, Mn(VII)) is widely applied at the initial stage of water treatment to, e.g., abate taste and odor compounds, Mn(II) and Fe(II). However, its selectivity limits its application for micropollutant abatement. Hydrogen peroxide (H2O2), whi ...

AMER CHEMICAL SOC2021

Deciphering Iron-Dependent Activity in Oxygen Evolution Catalyzed by Nickel-Iron Layered Double Hydroxide

Xile Hu, Lichen Bai, Seunghwa Lee

Nickel iron oxyhydroxide is the benchmark catalyst for the oxygen evolution reaction (OER) in alkaline medium. Whereas the presence of Fe ions is essential to the high activity, the functions of Fe are currently under debate. Using oxygen isotope labeling ...

Wiley-VCH Verlag GmbH2020

Construction of MOF/Polymer Composites for Metal Ion Capture

Daniel Teav Sun

Metal ion capture is of environmental and economic significance. The industrial revolutions have discharged increasing amounts of heavy and precious metals into complex water sources. The key is that these types of metal ions tend to be at trace amounts in ...

EPFL2020

Mechanism of Oxygen Evolution Catalyzed by Cobalt Oxyhydroxide: Cobalt Superoxide Species as a Key Intermediate and Dioxygen Release as a Rate-Determining Step

Xile Hu, Seunghwa Lee, Aliki Moysiadou

The oxygen evolution reaction (OER) is the performance-limiting half reaction of water splitting, which can be used to produce hydrogen fuel using renewable energies. Whereas a number of transition metal oxides and oxyhydroxides have been developed as prom ...

2020

Phyllomanganate vein-infillings in faulted and Al-poor regoliths of the New Caledonian ophiolite: periodic and sequential crystallization of Ni-asbolane, Alk-birnessite and H-birnessite

Gabrielle Dublet

Mineralogy, chemistry and spatial distribution of phyllomanganates, found in abundance at the bottom of thick Ni-laterite deposits, were established on dislocated vein-infillings showing banded and fibrous patterns (i.e. colloforms with rows of tiny boxwor ...

2019

A catalytically active [Mn]-hydrogenase incorporating a non-native metal cofactor

Xile Hu, Farzaneh Fadaei Tirani, Matthew Wodrich, Huijie Pan

Nature carefully selects specific metal ions for incorporation into the enzymes that catalyse the chemical reactions necessary for life. Hydrogenases, enzymes that activate molecular H-2, exclusively utilize Ni and Fe in [NiFe]-, [FeFe]- and [Fe]-hydrogean ...

2019

Manganese-mediated reductive amidation of esters with nitroarenes

Xile Hu, Chi Wai Cheung, Peng Wang, Ning Shen

Amides are ubiquitous molecules in nature and in synthetic chemistry. Here we report a convenient and efficient method to synthesize N-aryl amides via amidation of esters with nitroarenes. In the presence of manganese metal, this amidation proceeded smooth ...

ROYAL SOC CHEMISTRY2019

Manganese-Mediated Reductive Transamidation of Tertiary Amides with Nitroarenes

Xile Hu, Chi Wai Cheung

Amides are an important class of organic compounds, which have widespread industrial applications. Transamidation of amides is a convenient method to generate new amides from existing ones. Tertiary amides, however, are challenging substrates for transamid ...

2018

Interface microstructure formation of dissimilar Fe/Fe-Mn-C steel RSW joints

Léa Deillon

An experiment was developed to simulate the interface between liquid high manganese carbon steel and solid ultra-low alloyed steel in a thermal gradient, corresponding to the nugget/sheet interface of resistance spot welds. Despite the large difference in ...

Elsevier Science Sa2018

Building Composite Iron-Manganese Oxide Flowerlike Nanostructures: A Detailed Magnetic Study

Davide Deiana

Here we show that it is possible to produce different magnetic core multiple shell heterostructures from monodisperse Fe3O4 spherical magnetic seeds by finely controlling the amount of a manganese precursor and using, in a smart and simple way, a cation-ex ...

Amer Chemical Soc2017

Syntheses, structures and properties of cobalt and manganese complexes based on pyridine-2,3,5,6-tetracarboxylic acid

Chi Wai Cheung, Weijin Wang, Hong-Ling Gao

Two new complexes based on pyridine-2,3,5,6-tetracarboxylic acid(H(4)pdtc) as ligand, {[Co-2(pdtc)(H2O)(4)]center dot H2O}(n) (1) and {Mn-2(pdtc)(H2O)(4)}(n) (2), have been obtained by hydrothermal syntheses and characterized by IR, elemental analysis, X-r ...

Elsevier Science Bv2015

Phase-based manganese enhanced MRI, a new methodology to enhance brain cytoarchitectural contrast and study manganese uptake

Rolf Gruetter, José Pedro Rebelo Ferreira Marques, Rajika Maddage

Purpose As the magnetic susceptibility induced frequency shift increases linearly with magnetic field strength, the present work evaluates manganese as a phase imaging contrast agent and investigates the dose dependence of brain enhancement in comparison t ...

Wiley-Blackwell2014

Impact of microbial Mn oxidation on the remobilization of bioreduced U(IV)

Rizlan Bernier-Latmani, Kelly Lee Plathe

Effects of Mn redox cycling on the stability of bioreduced U(IV) are evaluated here. U(VI) can be biologically reduced to less soluble U(IV) species and the stimulation of biological activity to that end is a salient remediation strategy; however, the stab ...

American Chemical Society2013

Manganese in dwarf spheroidal galaxies

Pascale Jablonka, Pierre North

We provide manganese abundances (corrected for the effect of the hyperfine structure) for a large number of stars in the dwarf spheroidal galaxies Sculptor and Fornax, and for a smaller number in the Carina and Sextans dSph galaxies. Abundances had already ...

2012