Publications associées à Effect of Fe-enrichment on seismic properties of perovskite and post-perovskite in the deep lower mantle

Mixed ionic-electronic conduction in Ruddlesden-Popper and Dion-Jacobson layered hybrid perovskites with aromatic organic spacers

Michael Graetzel, Davide Moia, Joachim Maier, Jovana Milic, Algirdas Ducinskas, Mina Jung

The understanding of mixed ionic-electronic conductivity in hybrid perovskites has enabled major advances in the development of optoelectronic devices based on this class of materials. While recent investigations revealed the potential of using dimensional ...

Royal Society of Chemistry2024

New tools for phase segmentation and denoising of analytical STEM data for enhanced chemical sensitivity, applied to Earth mantle research

Hui Chen

This thesis is dedicated to developing innovative methodologies that improve elemental quantification in scanning transmission electron microscopy (STEM) using energy-dispersive X-ray spectroscopy (EDXS). The primary motivation stems from a geochemistry pr ...

EPFL2023

First-Principles Thermodynamics of CsSnI3

Nicola Marzari, Lorenzo Monacelli

CsSnI3 is a promising ecofriendly solution for energy harvesting technologies. It exists at room temperature in either a black perovskite polymorph or a yellow 1D double-chain, which irreversibly deteriorates in the air. In this work, we unveil the relativ ...

AMER CHEMICAL SOC2023

The Impact of Spacer Size on Charge Transfer Excitons in Dion–Jacobson and Ruddlesden–Popper Layered Hybrid Perovskites

Michael Graetzel, Jacques-Edouard Moser, Aaron Tomas Terpstra, Loï Charles Carbone, Jovana Milic, George Cameron Fish, Masaud Hassan S Almalki, Algirdas Ducinskas, Lukas Pfeifer

Organic materials can tune the optical properties in layered (2D) hybrid perovskites, although their impact on photophysics is often overlooked. Here, we use transient absorption spectroscopy to probe the Dion−Jacobson (DJ) and Ruddlesden−Popper (RP) 2D pe ...

2023

Synthesis and Characterization of Functionalized Spacer Cations for the Incorporation in Layered Perovskites

Simon Nussbaum

Layered hybrid organic-inorganic perovskite (LHOIP) materials are an emerging class of semiconductors endorsed as a more stable alternative compared to the more widely investigated 3D hybrid organic-inorganic halide perovskites (HOIP). Consisting of altern ...

EPFL2023

Materials engineering for improved stability of perovskite solar cells

Yeonju Kim

Halide perovskites have gained tremendous attention over the past decade, but the poor stability of perovskite solar cells (PSCs) under operating conditions hampers their practical application. This thesis investigates materials that can be used to enhance ...

EPFL2023

Nanoindentation of embedded particles

Andreas Mortensen, Alejandra Inés Slagter, Joris Pierre Everaerts

We address the effect of elastic inhomogeneity on elastic modulus and hardness determinations made by depth-sensing indentations performed on individual particles embedded within a matrix of different elastic modulus. Finite element simulations and nanoind ...

SPRINGER HEIDELBERG2023

Molecularly Tailored Surface Defect Modifier for Efficient and Stable Perovskite Solar Cells

Michael Graetzel, Shaik Mohammed Zakeeruddin, Yelin Hu, Miao Chen, Hongwei Zhu, Zhongjin Shen, Yinghui Wu, Jialin Wang

Surface defects cause non-radiative charge recombination and reduce the photovoltaic performance of perovskite solar cells (PSCs), thus effective passivation of defects has become a crucial method for achieving efficient and stable devices. Organic ammoniu ...

WILEY-V C H VERLAG GMBH2023

All-inorganic halide perovskites for air-processed "n-i-p" monolithic perovskite/organic hybrid tandem solar cells exceeding 23% efficiency

Mohammad Khaja Nazeeruddin

All-perovskite tandem solar cells recently surpassed 26% power conversion efficiency using a Sn(ii)-based halide perovskite rear subcell, which introduces several issues related to the chemical instability and the effectiveness of common, inexpensive inter ...

Royal Soc Chemistry2023

Tuning Napththalenediimide Cations for Incorporation into Ruddlesden–Popper-Type Hybrid Perovskites

Jacques-Edouard Moser, Jun Ho Yum, Kevin Sivula, Etienne Christophe Socie, Liang Yao, Simon Nussbaum

Layered hybrid organic−inorganic perovskite (LHOIP) materials constructed with low-band-gap chromophore-based organic spacer cations are anemerging class of materials that promise unique tunability of their optoelectronic properties. However, the large siz ...

2022

On the bulk compressibility of close-packed particles and their composites

Andreas Mortensen, Maria Gabriella Tarantino

The hydrostatic compaction of composites comprising a closely-packed particle-bed filled by a dense matrix is measured experimentally using a fluid-pressurization apparatus. A highly compliant polymer or pure aluminium are infiltrated into preforms of pack ...

ELSEVIER SCI LTD2022

Exploring new avenues for perovskite photovoltaics: Molecular functionalization of layered lead-halide perovskites and defect mitigation in lead-free double perovskites

Barbara Alexandra Primera Darwich

Halide perovskites have seen, over the past years, a tremendous increase in photovoltaic power conversion efficiencies as device working mechanisms are unveiled. Lead halide perovskites are at the forefront of halide perovskite research given their intrigu ...

EPFL2022

Investigation in Crystal Growth/Morphology and Interface Engineering of Perovskite Solar Cells by Different Deposition Methods

Nadja Isabelle Desiree Klipfel

A new and promising technology has emerged to compete with traditional silicon photovoltaic semiconductors. The low material and processing costs and high-power conversion efficiencies of organic-inorganic metal halide perovskites make these a promising te ...

EPFL2022

Anti-Jahn-Teller effect induced ultrafast insulator to metal transition in perovskite BaBiO3

Changpeng Lin, Ben Xu

The Jahn-Teller (JT) effect involves the ions M with a degenerate electronic state distorting the corner-sharing MO6 octahedra to lift the degeneracy, inducing strong coupling of electrons to lattice, and mediating the exotic properties in perovskite oxide ...

NATURE PORTFOLIO2022

Effect of different ions on dissolution rates of silica and feldspars at high pH

Karen Scrivener, Barbara Lothenbach, Mahsa Bagheri, Mahdieh Shakoorioskooie

The dissolution kinetics of silica-containing minerals in aggregates influences strongly the process of ASR in concrete. In this paper, the effect of different ions on the dissolution rates of SiO2 (amorphous and quartz) and feldspars at high pH values was ...

Pergamon-Elsevier Science Ltd2022

Hysteresis-Free Planar Perovskite Solar Module with 19.1% Efficiency by Interfacial Defects Passivation

Ulf Anders Hagfeldt, Bowen Yang, Jiajia Suo

In few years, perovskite solar devices have reached high efficiency on lab scale cells. Upscaling to module size, effective perovskite recipe and posttreatment are of paramount importance to the breakthrough of the technology. Herein this work, the develop ...

WILEY-V C H VERLAG GMBH2022

Composition and Pressure Effects on Partitioning of Ferrous Iron in Iron-Rich Lower Mantle Heterogeneities

Marco Cantoni, Philippe Gillet, Farhang Nabiei, Susannah McGregor Dorfman, James Badro, Charles-Edouard Boukaré

Both seismic observations of dense low shear velocity regions and models of magma ocean crystallization and mantle dynamics support enrichment of iron in Earth’s lowermost mantle. Physical properties of iron-rich lower mantle heterogeneities in the modern ...

2021

Investigating Magma Ocean Solidification on Earth Through Laser‐Heated Diamond Anvil Cell Experiments

Marco Cantoni, Cécile Hébert, Philippe Gillet, Farhang Nabiei, James Badro, Charles-Edouard Boukaré

We carried out a series of silicate fractional crystallization experiments at lower mantle pressures using the laser-heated diamond anvil cell. Phase relations and the compositional evolution of the cotectic melt and equilibrium solids along the liquid lin ...

2021

The Effects of Planetary and Stellar Parameters on Brittle Lithospheric Thickness

Marie Estelle Solange Violay, Michael Heap

The thicknesss of the brittle lithosphere—the outer portion of a planetary body that fails via fracturing— plays a key role in the geological processes of that body. The properties of both a planet and its host star can influence that thickness, and the po ...

2021

Layered Hybrid Formamidinium Lead Iodide Perovskites: Challenges and Opportunities

Michael Graetzel, Shaik Mohammed Zakeeruddin, Jovana Milic

Hybrid halide perovskite materials have become one of the leading candidates for various optoelectronic applications. They are based on organic-inorganic structures defined by the AMX(3) composition, were A is the central cation that can be either organic ...

AMER CHEMICAL SOC2021