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Concept

Ammonium

Publications associées (26)

Probing structural and dynamic properties of MAPbCl3 hybrid perovskite using Mn2+ EPR

Michael Allan Hope, Yuxuan Zhang

Hybrid methylammonium (MA) lead halide perovskites have emerged as materials exhibiting excellent photovoltaic performance related to their rich structural and dynamic properties. Here, we use multifrequency (X-, Q-, and W-band) electron paramagnetic reson ...

Royal Soc Chemistry2024

Investigations about the Chemistry of Tetraarylethene- and Iridium-Based Luminophores

Anastasia Gitlina

The work described in this thesis focuses on two classes of luminophores: tetraarylethene-based polymers and Ir(III) complexes with orthometalated ligands. Tetraarylethene-based polymers show aggregation-induced emission (AIE) and they are of interest for ...

EPFL2024

Bulk size-resolved chemical composition and mass concentration of non-refractory submicron aerosols measured in the Swiss container during MOSAiC 2019/2020

Julia Schmale, Ivo Fabio Beck, Hélène Paule Angot, Lubna Dada, Benjamin Jérémy Laurent Heutte

This dataset contains the bulk size-resolved chemical composition and mass concentration of non-refractory submicron aerosols (NR-PM1) measured during the MOSAiC expedition from October 2019 to July 2020. These include the mass concentrations of sulfate (S ...

Zenodo2023

Seasonal Aerosol Acidity, Liquid Water Content and Their Impact on Fine Urban Aerosol in SE Canada

Athanasios Nenes, Andrea Mario Arangio

This study explores the drivers of aerosol pH and their impact on the inorganic fraction and mass of aerosol in the S.E. Canadian urban environments of Hamilton and Toronto, Ontario. We find that inter-seasonal pH variability is mostly driven by temperatur ...

MDPI2022

Oxidase-Type C-H/C-H Coupling Using an Isoquinoline-Derived Organic Photocatalyst

Xile Hu, Lei Zhang

Oxidase-type oxidation is an attractive strategy in organic synthesis due to the use of O-2 as the terminal oxidant. Organic photocatalysis can effect metal-free oxidase chemistry. Nevertheless, current methods are limited in reaction scope, possibly due t ...

Wiley-VCH Verlag GmbH2022

Structure-property relationships and mixed conductivity in layered hybrid perovskites based on phenyl-derived spacers

Algirdas Ducinskas

Hybrid halide perovskites are currently one of the most studied semiconductors. However, due to poor intrinsic and extrinsic stability, further developments to commercialize devices based on hybrid halide perovskites are limited. Many different strategies ...

EPFL2022

Surface Reconstruction Engineering with Synergistic Effect of Mixed‐Salt Passivation Treatment toward Efficient and Stable Perovskite Solar Cells

Michael Graetzel, Shaik Mohammed Zakeeruddin, Ulf Anders Hagfeldt, Bowen Yang, Hui-Seon Kim, Jiajia Suo, Yeonju Kim

Surface passivation treatment is a widely used strategy to resolve trap-mediated nonradiative recombination toward high-efficiency metal-halide perovskite photovoltaics. However, a lack of passivation with mixture treatment has been investigated, as well a ...

2021

Constraining the response factors of an extractive electrospray ionization mass spectrometer for near-molecular aerosol speciation

Julia Schmale

Online characterization of aerosol composition at the near-molecular level is key to understanding chemical reaction mechanisms, kinetics, and sources under various atmospheric conditions. The recently developed extractive electrospray ionization time-of-f ...

2021

Cluster Catalysis with Lattice Oxygen: Tracing Oxygen Transport from a Magnetite (001) Support onto Small Pt Clusters

Wolfgang Harbich, Giulia Elisabetta Pacchioni, Ke Zhang

Oxidation catalysis on reducible oxide-supported small metal clusters often involves lattice oxygen. The present work aims at differentiating whether the reaction takes place at the cluster/support interface or on the cluster. To that purpose, we trace the ...

AMER CHEMICAL SOC2021

High-resolution hybrid inversion of IASI ammonia columns to constrain US ammonia emissions using the CMAQ adjoint model

Athanasios Nenes

Ammonia (NH3) emissions have large impacts on air quality and nitrogen deposition, influencing human health and the well-being of sensitive ecosystems. Large uncertainties exist in the "bottom-up" NH3 emission inventories due to limited source information ...

Copernicus GmbH2021

A polymeric ionic liquid catalyst for the N-formylation and N-methylation of amines using CO2/PhSiH3

Paul Joseph Dyson, Andreas Züttel, Zhaofu Fei, Kyriakos Stylianou, Arunraj Chidambaram, Aswin Gopakumar, Dmitry Vasilyev, Serhii Shyshkanov

We describe a polymeric ionic liquid (PIL) derived from trimethyl(p-vinylbenzyl)ammonium chloride ([VBTAm]Cl) that efficiently catalyzes the N-formylation of amines employing CO2 and PhSiH3 at room temperature with low catalyst loadings in near-quantitativ ...

2020

Ammonium is the preferred source of nitrogen for planktonic foraminifer and their dinoflagellate symbionts

Anders Meibom, Emmanuelle Geslin, Charlotte Madeleine Nicole Lekieffre

The symbiotic planktonic foraminiferaOrbulina universainhabits open ocean oligotrophic ecosystems where dissolved nutrients are scarce and often limit biological productivity. It has previously been proposed thatO. universameets its nitrogen (N) requiremen ...

ROYAL SOC2020

Using High-Temporal-Resolution Ambient Data to Investigate Gas-Particle Partitioning of Ammonium over Different Seasons

Athanasios Nenes

Ammonium is one of the dominant inorganic water-soluble ions in fine particulate matter (PM2.5). In this study, source apportionment and thermodynamic equilibrium models were used to analyze the relationship between pH and the partitioning of ammonium (eps ...

AMER CHEMICAL SOC2020

Heterotrophic Foraminifera Capable of Inorganic Nitrogen Assimilation

Anders Meibom, Emmanuelle Geslin, Charlotte Madeleine Nicole Lekieffre

Nitrogen availability often limits biological productivity in marine systems, where inorganic nitrogen, such as ammonium is assimilated into the food web by bacteria and photoautotrophic eukaryotes. Recently, ammonium assimilation was observed in kleptopla ...

Frontiers Media SA2020

Evolution of nitrogen concentration and ammonia production in N-2-seeded H-mode discharges at ASDEX Upgrade

Olivier Sauter, Basil Duval, Richard Pitts, Timothy Goodman, Stefano Coda, Yann Camenen, Marco Wischmeier, Nicola Vianello, Federico Alberto Alfredo Felici, Cristian Sommariva, Laurie Porte, Alberto Bottino, Emiliano Fable, Antoine Pierre Emmanuel Alexis Merle, Andrea Scarabosio, Doohyun Kim, Haomin Sun, Dávid Wágner, Thomas Binderup Jensen

Ammonia formation was studied in a series of dedicated nitrogen seeded H-mode discharges at ASDEX Upgrade. The evolution of ammonia formation was investigated with a reference phase before the seeding, and a long, stable flat-top nitrogen-seeded phase. It ...

IOP Publishing Ltd2019

Specific Ion Effects at the Interface of Nanometer-Sized Droplets in Water: Structure and Stability

Sylvie Roke, Halil Ibrahim Okur, Evangelia Zdrali

The interaction of ions with interfaces influences numerous processes in chemistry, physics, and biology, while different ion species behave differently at hydrophobic or hydrophilic interfaces. Despite its importance, ion specificity and its relation to s ...

2019

Catalyst Proximity-Induced Functionalization of h-BN with Quat Derivatives

Magalí Alejandra Lingenfelder, Bart Willem Stel, Gabriele Tocci, Huanyao Cun

Inert single-layer boron nitride (h-BN) grown on a catalytic metal may be functionalized with quaternary ammonium compounds (quats) that are widely used as nonreactive electrolytes. We observe that the quat treatment, which facilitates the electrochemical ...

2019

Atomic-level passivation mechanism of ammonium salts enabling highly efficient perovskite solar cells

Michael Graetzel, Shaik Mohammed Zakeeruddin, David Lyndon Emsley, Jacques-Edouard Moser, Jingshan Luo, Dominik Józef Kubicki, Fabrizio Giordano, Brennan James Walder, Andrés Burgos Caminal, Essa Awadh R Alharbi, Anwar Qasem M Alanazi, Alexander Roland Uhl

The high conversion efficiency has made metal halide perovskite solar cells a real break-through in thin film photovoltaic technology in recent years. Here, we introduce a straight-forward strategy to reduce the level of electronic defects present at the i ...

Nature Research2019

Mixed cation perovskite solid state solar cell and fabrication thereof

Michael Graetzel, Shaik Mohammed Zakeeruddin, Wolfgang Richard Tress, Michael Saliba, Konrad Domanski, Jiyoun Seo

A perovskite material including an organic-inorganic perovskite structure of formula (I), AnMX3 (I), n being the number of cation A and an integer >4, A being a monovalent cation selected from inorganic cations Ai and/or from organic cations Ao, M being a ...

2018

The underappreciated role of nonvolatile cations in aerosol ammonium-sulfate molar ratios

Athanasios Nenes, Hairun Guo

Overprediction of fine-particle ammonium-sulfate molar ratios (R) by thermodynamic models is suggested as evidence for interactions with organic constituents that inhibit the equilibration of gas-phase ammonia with aerosol sulfate and questions the equilib ...

Copernicus Publications2018