École Polytechnique Fédérale de Lausanne

About: École Polytechnique Fédérale de Lausanne is a facility organization based out in Lausanne, Switzerland. It is known for research contribution in the topics: Population & Catalysis. The organization has 44041 authors who have published 98296 publications receiving 4372092 citations. The organization is also known as: EPFL & ETHL.

Transition Metal Oxides as Electrocatalysts for the Oxygen Evolution Reaction in Alkaline Solutions: An Application-Inspired Renaissance

Abstract: Water splitting is the essential chemical reaction to enable the storage of intermittent energies such as solar and wind in the form of hydrogen fuel. The oxygen evolution reaction (OER) is often considered as the bottleneck in water splitting. Though metal oxides had been reported as OER electrocatalysts more than half a century ago, the recent interest in renewable energy storage has spurred a renaissance of the studies of transition metal oxides as Earth-abundant and nonprecious OER catalysts. This Perspective presents major progress in several key areas of the field such as theoretical understanding, activity trend, in situ and operando characterization, active site determination, and novel materials. A personal overview of the past achievements and future challenges is also provided.

High-Efficiency Organic-Dye-Sensitized Solar Cells Controlled by Nanocrystalline-TiO2 Electrode Thickness

Abstract: Reference LPI-ARTICLE-2006-008doi:10.1002/adma.200502540View record in Web of Science Record created on 2006-05-03, modified on 2016-08-08

In Vivo Fluorescence Spectroscopy and Imaging for Oncological Applications

Abstract: Keywords: Photomedicine group Reference LPAS-ARTICLE-1998-003View record in Web of Science Record created on 2007-07-20, modified on 2016-08-08

Improved performance and stability of perovskite solar cells by crystal crosslinking with alkylphosphonic acid ω-ammonium chlorides.

Abstract: In the past few years, organic-inorganic halide perovskites have rapidly emerged as promising materials for photovoltaic applications, but simultaneously achieving high performance and long-term stability has proved challenging. Here, we show a one-step solution-processing strategy using phosphonic acid ammonium additives that results in efficient perovskite solar cells with enhanced stability. We modify the surface of methylammonium lead triiodide (CH3NH3PbI3) perovskite by spin-coating its precursor solution in the presence of butylphosphonic acid 4-ammonium chloride. Morphological, structural and elemental analyses show that the phosphonic acid ammonium additive acts as a crosslink between neighbouring grains in the perovskite structure, through strong hydrogen bonding of the -PO(OH)2 and -NH3(+) terminal groups to the perovskite surface. The additives facilitate the incorporation of the perovskite within a mesoporous TiO2 scaffold, as well as the growth of a uniform perovskite layer at the surface, enhancing the material's photovoltaic performance from 8.8 to 16.7% as well as its resistance to moisture.

Materials interface engineering for solution-processed photovoltaics

Abstract: Advances in solar photovoltaics are urgently needed to increase the performance and reduce the cost of harvesting solar power. Solution-processed photovoltaics are cost-effective to manufacture and offer the potential for physical flexibility. Rapid progress in their development has increased their solar-power conversion efficiencies. The nanometre (electron) and micrometre (photon) scale interfaces between the crystalline domains that make up solution-processed solar cells are crucial for efficient charge transport. These interfaces include large surface area junctions between photoelectron donors and acceptors, the intralayer grain boundaries within the absorber, and the interfaces between photoactive layers and the top and bottom contacts. Controlling the collection and minimizing the trapping of charge carriers at these boundaries is crucial to efficiency.