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David Lyndon Emsley

Cette personne a quitté l’EPFL

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Publications associées (166)

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Structure determination of an amorphous drug through large-scale NMR predictions

Manuel Cordova, David Lyndon Emsley, Albert Hofstetter, Federico Maria Paruzzo, Martins Balodis, Pierrick Berruyer, Bruno Simões de Almeida

Knowledge of the structure of amorphous solids can direct, for example, the optimization of pharmaceutical formulations, but atomic-level structure determination in amorphous molecular solids has so far not been possible. Solid-state nuclear magnetic reson ...

Nature Research2021

Iron incorporation in synthetic precipitated calcium silicate hydrates

Paul Bowen, Jirawan Siramanont, David Lyndon Emsley, Brennan James Walder

Effect of Fe3+ on the precipitation of synthetic calcium silicate hydrates (C-S-H) under controlled conditions has been evaluated. Using extremely basic either initial calcium nitrate or sodium silicate solutions (pH > 11), incipient formation of ferrihydr ...

Pergamon-Elsevier Science Ltd2021

Imaging Radial Distribution Functions of Complex Particles by Relayed Dynamic Nuclear Polarization

Arthur César Pinon, David Lyndon Emsley, Pierrick Berruyer

The physical properties of many modern multi-component materials are determined by their internal microstructure. Tools capable of characterizing complex nanoscale architectures in composite materials are, therefore, essential to design materials with targ ...

2023

Cd-113 Solid-State NMR at 21.1 T Reveals the Local Structure and Passivation Mechanism of Cadmium in Hybrid and All-Inorganic Halide Perovskites

Dominik Józef Kubicki, David Lyndon Emsley, Albert Hofstetter, Brennan James Walder, Daniel Prochowicz

Cadmium doping has recently emerged as an efficacious strategy for defect suppression and band gap tuning in hybrid as well as all-inorganic halide perovskites. However, the cadmium speciation in these materials is unknown. Here, we use high-field cadmium- ...

2020

Structure of Lipid Nanoparticles Containing siRNA or mRNA by Dynamic Nuclear Polarization-Enhanced NMR Spectroscopy

Arthur César Pinon, David Lyndon Emsley, Aaron James Rossini, Jasmine Viger-Gravel

Here, we show how dynamic nuclear polarization (DNP) NMR spectroscopy experiments permit the atomic level structural characterization of loaded and empty lipid nanoparticles (LNPs). The LNPs used here were synthesized by the microfluidic mixing technique a ...

2018

Optically Enhanced Solid-State H-1 NMR Spectroscopy

Jean-Philippe Ansermet, Jonas Milani, Dominik Józef Kubicki, David Lyndon Emsley, Aaron James Rossini, Claudia Esther Avalos, Gabriele Stevanato, Aditya Mishra, Michael Allan Hope, Federico De Biasi, Saumya Badoni

Low sensitivity is the primary limitation to extendingnuclearmagnetic resonance (NMR) techniques to more advanced chemical andstructural studies. Photochemically induced dynamic nuclear polarization(photo-CIDNP) is an NMR hyperpolarization technique where ...

AMER CHEMICAL SOC2023

Endogenous O-17 Dynamic Nuclear Polarization of Gd-Doped CeO2 from 100 to 370 K

David Lyndon Emsley, Snaedis Björgvinsdóttir, Michael Allan Hope

O-17 NMR is an invaluable tool to study the structure and dynamics of oxide materials but remains challenging to apply in many systems. Even with isotopic enrichment, studies of samples with low masses and/or concentrations of the active species, such as t ...

2021

Atomistic origins of the limited phase stability of Cs+-rich FAxCs(1-x)PbI3 mixtures

Michael Graetzel, Ursula Röthlisberger, Simone Meloni, Dominik Józef Kubicki, David Lyndon Emsley, Ariadni Boziki, Aditya Mishra

Mixed cation perovskites, [HC(NH2)2]xCs(1-x)PbI3, (FAxCs(1-x)PbI3) with x=0.8 achieve high solar cell power conversion efficiencies (PCEs) while exhibiting long-term stability under ambient conditions. In this work, we perform density functional theory (DF ...

2020

Crown Ether Modulation Enables over 23% Efficient Formamidinium-Based Perovskite Solar Cells

Michael Graetzel, Shaik Mohammed Zakeeruddin, Mounir Driss Mensi, Ursula Röthlisberger, Ulf Anders Hagfeldt, Jun Ho Yum, Kevin Sivula, Marko Mladenovic, David Lyndon Emsley, Farzaneh Jahanbakhshi, Jovana Milic, Dan Ren, Aditya Mishra, Felix Thomas Eickemeyer, Hong Zhang, Michael Allan Hope, Jun Li, Anurag Krishna, Olivier Ouellette, Zhiwen Zhou

The use of molecular modulators to reduce the defect density at the surface and grain boundaries of perovskite materials has been demonstrated to be an effective approach to enhance the photovoltaic performance and device stability of perovskite solar cell ...

2020

Supramolecular Engineering for Formamidinium-Based Layered 2D Perovskite Solar Cells: Structural Complexity and Dynamics Revealed by Solid-State NMR Spectroscopy

Michael Graetzel, Shaik Mohammed Zakeeruddin, Amita Ummadisingu, Mohammad Ibrahim Dar, Dominik Józef Kubicki, Jeong-Hyeok Im, David Lyndon Emsley, Jiyoun Seo, Yang Li, Jovana Milic, Marco Alejandro Ruiz Preciado

Perovskite solar cells are one of the most promising photovoltaic technologies, although their molecular level design and stability toward environmental factors remain a challenge. Layered 2D Ruddlesden-Popper perovskite phases feature an organic spacer bi ...

WILEY-V C H VERLAG GMBH2019

Phase Segregation in Cs-, Rb- and K-Doped Mixed-Cation (MA)(x)(FA)(1-x)Pbl(3) Hybrid Perovskites from Solid-State NMR

Michael Graetzel, Shaik Mohammed Zakeeruddin, Dominik Józef Kubicki, David Lyndon Emsley, Albert Hofstetter, Daniel Prochowicz

Hybrid (organic-inorganic) multication lead halide perovskites hold promise for a new generation of easily processable solar cells. Best performing compositions to date are multiple-cation solid alloys of formamidinium (FA), methylammonium (MA), cesium, an ...

American Chemical Society2017

Formamidinium Incorporates into Rb-based Non-Perovskite Phases in Solar Cell Formulations

Michael Graetzel, David Lyndon Emsley, Michael Allan Hope, Lukas Pfeifer, Ümmügülsüm Günes, Yuxuan Zhang, Likai Zheng

Organic-inorganic hybrid perovskite materials, such as formamidinium lead iodide (FAPbI3), are among the most promising emerging photovoltaic materials. However, the spontaneous phase transition from the photoactive perovskite phase to an inactive non-pero ...

Wiley-VCH Verlag GmbH2024

Strain-induced rubidium incorporation into wide-bandgap perovskites reduces photovoltage loss

Michael Graetzel, Shaik Mohammed Zakeeruddin, Mounir Driss Mensi, Ursula Röthlisberger, David Lyndon Emsley, Pascal Alexander Schouwink, Jing Gao, Felix Thomas Eickemeyer, Michael Allan Hope, Lukas Pfeifer, Nikolaos Lempesis, Virginia Carnevali, Ümmügülsüm Günes, Lorenzo Agosta, Yuxuan Zhang, Likai Zheng, Vladislav Slama, Francesco Biasoni

A-site cation mixing can enhance the photovoltaic performance of a wide-bandgap (WBG) perovskite, but rubidium (Rb) cation mixing generally forms a nonperovskite phase. We report that lattice strain locks Rb ions into the α-phase of the lattice of a triple ...

American Association for the Advancement of Science (AAAS)2025

Design Principles for the Development of Gd(III) Polarizing Agents for Magic Angle Spinning Dynamic Nuclear Polarization

Anne-Sophie Chauvin, Marinella Mazzanti, David Lyndon Emsley, Gabriele Stevanato, Chad Thomas Palumbo, Yu Rao, Megan Renee Keener, Amrit Venkatesh

Nuclear magnetic resonance suffers from an intrinsically low sensitivity, which can be overcome by dynamic nuclear polarization (DNP). Gd(III) complexes are attractive exogenous polarizing agents for magic angle spinning (MAS) DNP due to their high chemica ...

2022

Theory and simulations of homonuclear three-spin systems in rotating solids

David Lyndon Emsley, Gabriele Stevanato, Pinelopi Moutzouri, Bruno Simões de Almeida

The homonuclear dipolar coupling is the internal spin interaction that contributes the most to the line shapes in magic-angle-spinning (MAS) H-1 NMR spectra of solids, and linewidths typically extend over several hundred Hertz, limiting the H-1 resolution. ...

2021

Homonuclear Decoupling in H-1 NMR of Solids by Remote Correlation

David Lyndon Emsley, Federico Maria Paruzzo, Gabriele Stevanato, Pinelopi Moutzouri, Bruno Simões de Almeida

The typical linewidths of H-1 NMR spectra of powdered organic solids at 111 kHz magic-angle spinning (MAS) are of the order of a few hundred Hz. While this is remarkable in comparison to the tens of kHz observed in spectra of static samples, it is still th ...

Wiley-VCH Verlag GmbH2020

Guanine‐Stabilized Formamidinium Lead Iodide Perovskites

Shaik Mohammed Zakeeruddin, Ursula Röthlisberger, Ulf Anders Hagfeldt, Amita Ummadisingu, Marko Mladenovic, Dominik Józef Kubicki, David Lyndon Emsley, Linfeng Pan, Paramvir Ahlawat, Yuhang Liu, Jovana Milic, Dan Ren, Marco Alejandro Ruiz Preciado

Formamidinium (FA) lead iodide perovskite materials feature promising photovoltaic performances and superior thermal stabilities. However, conversion of the perovskite α‐FAPbI3 phase to the thermodynamically stable yet photovoltaically inactive δ‐FAPbI3 ph ...

2020

Ba-induced phase segregation and band gap reduction in mixed-halide inorganic perovskite solar cells

Michael Graetzel, Ulf Anders Hagfeldt, Dominik Józef Kubicki, Wolfgang Richard Tress, Jingshan Luo, David Lyndon Emsley, Albert Hofstetter, Zaiwei Wang

All-inorganic metal halide perovskites are showing promising development towards efficient long-term stable materials and solar cells. Element doping, especially on the lead site, has been proved to be a useful strategy to obtain the desired film quality a ...

Nature Research2019

Line narrowing in H-1 NMR of powdered organic solids with TOP-CT-MAS experiments at ultra-fast MAS

David Lyndon Emsley, Brennan James Walder, Federico Maria Paruzzo

The residual broadening observed in H-1 spectra of rigid organic solids at natural abundance under 111 kHz magic angle spinning (MAS) is typically a few hundred Hertz. Here we show that refocusable and non-refocusable interactions contribute roughly equall ...

Academic Press Inc - Elsevier Science2019

Core-Shell Structure of Organic Crystalline Nanoparticles Determined by Relayed Dynamic Nuclear Polarization NMR

Arthur César Pinon, David Lyndon Emsley, Jasmine Viger-Gravel

The structure of crystalline nanoparticles (CNPs) is determined using dynamic nuclear polarization (DNP) enhanced NMR spectroscopy experiments. The CNPs are composed of a crystalline core containing an active pharmaceutical ingredient (compound P), coated ...

AMER CHEMICAL SOC2018