Publications associées à White-light phosphorescence emission from a single molecule: application to OLED

Single molecule fluorescence and phosphorescence studies using a scanning tunneling microscope

This thesis investigates novel single-molecule luminescence phenomena at their inherent, sub-molecular length scale. The microscopic understanding of luminescence processes will be crucial for the continued improvement of organic optoelectronic and semicon ...

EPFL2022

Delineating Conformation Control in the Photophysical Behaviour of a Molecular Donor-Acceptor-Donor Triad

Shubhajit Das

Mechanochromic luminescent materials, exhibiting a change in luminescence behavior under external stimuli have emerged as one of the promising candidates for upcoming efficient OLEDs. Recently mechanochromic luminescence was reported in a donor-acceptor-do ...

WILEY-V C H VERLAG GMBH2021

Ion and Trap Induced Dynamic Phenomena in Salt Semiconductor Devices

Matthias Diethelm

State-of-the-art organic light-emitting diodes (OLEDs) used in commercial display technology are complex multilayer structures. In contrast, the light-emitting electrochemical cell (LEC) can be built from a single emissive layer sandwiched between two elec ...

EPFL2021

A general framework for non-exponential delayed fluorescence and phosphorescence decay analysis, illustrated on Protoporphyrin IX

Georges Wagnières, Aurelien Stephen Arnaud Gregor, Emmanuel Louis Arthur Gerelli, Jaroslava Joniová

Delayed fluorescence (DF) is a long-lived luminescence process used in a variety of applications ranging from oxygen sensing in biological tissues to organic Light Emitting Diodes. In common cases, DF results from the deexcitation of the first excited trip ...

2020

Nanoscale Lithography and Thermometry with Thermal Scanning Probes

Samuel Tobias Howell, Samuel Zimmermann

Thermal scanning probe lithography (t-SPL) is an advanced lithography technique in which a heated atomic force microscope tip locally modifies a sample material. Due to the nanometer-sized tip apex diameter, t-SPL enables patterning of sub-10 nm structures ...

EPFL2018

Phosphorescent Neutral Iridium (III) Complexes for Organic Light-Emitting Diodes

Mohammad Khaja Nazeeruddin, Aron Joel Huckaba

The development of transition metal complexes for application in light-emitting devices is currently attracting significant research interest. Among phosphorescent emitters, those involving iridium (III) complexes have proven to be exceedingly useful due t ...

Springer Verlag2017

Dual Luminescence, Interligand Decay, and Nonradiative Electronic Relaxation of Cyclometalated Iridium Complexes in Solution

Majed Chergui, Olivier Christian Bräm, Andrea Cannizzo, Mahsa Silatani, Enrico Pomarico

Femtosecond broadband photoluminescence studies are presented for Ir(ppy)(3) (Ir1), Ir(ppy)(2)(pic) (Ir2), Ir(ppy)(2)(bpy)(PF6) (Ir3), Ir(ppz)(3) (Ir4), and Ir(ppz)(2)dipy (Ir5) (where ppy = 2-phenylpyridine, pic = picolinate, bpy = 2,2'-bipyridine, ppz = ...

American Chemical Society2016

Ruthenium phenanthroimidazole complexes for near infrared light-emitting electrochemical cells

Mohammad Khaja Nazeeruddin, Cristina Roldán Carmona

By adding different electron donor moieties to the ancillary ligand in ruthenium(II) phenanthroimidazole complexes, we successfully designed near infrared light emitting complexes suitable for light emitting electro-chemical cells (LECs). By using a single ...

Royal Society of Chemistry2016

Gold nanoparticles: BSA (Bovine Serum Albumin) coating and X-ray irradiation produce variable-spectrum photoluminescence

Giorgio Margaritondo

We show that by using different x-ray irradiation times of BSA-coated Au nanoparticles (NPs) we can change their ultraviolet-stimulated photoluminescence and shift the spectral weight over the visible spectral range. This is due to the interplay of two emi ...

Elsevier Science Sa2015

Extreme Tuning of Redox and Optical Properties of Cationic Cyclometalated Iridium(III) Isocyanide Complexes

Michael Graetzel, Mohammad Khaja Nazeeruddin, Rosario Scopelliti

We report seven heteroleptic cationic iridium(III) complexes with cyclometalating N-arylazoles and alkyl/aryl isocyanides, ((CN)-N-boolean AND)(2)Ir(CNR)(2), and characterize two of them by crystal structure analysis. The complexes are air- and m ...

American Chemical Society2013

Charged Bis-Cyclometalated Iridium(III) Complexes with Carbene-Based Ancillary Ligands

Mohammad Khaja Nazeeruddin, Rosario Scopelliti, Julien Edouard Frey

Charged cydometalated (CN) iridium(III) complexes with carbene-based ancillary ligands are a promising family of deep-blue phosphorescent compounds. Their emission properties are controlled primarily by the main CN ligands, in contrast to the classic ...

American Chemical Society2013

The luminescence of NaxEu3+(2−x)/3MoO4 scheelites depends on the number of Eu-clusters occurring in their incommensurately modulated structure

Jean-Claude Bünzli, Gervais Chapuis, Alla Arakcheeva, Philip Pattison, Dmitry Logvinovich, Svetlana Eliseeva

Scheelite related compounds with general formula Mn(XO4)m are of interest owing to their optical properties, stability and relatively simple preparation. Eu3+-containing scheelites are considered as red emitting phosphors and the main factors affecting the ...

2012

Bright Blue Phosphorescence from Cationic Bis-Cyclometalated Iridium(III) Isocyanide Complexes

Michael Graetzel, Mohammad Khaja Nazeeruddin, Rosario Scopelliti

We report new bis-cyclometalated cationic indium(III) complexes ((CN)-N-boolean AND)(2)Ir(CN-tert-Bu)(2) that have tert-butyl isocyanides as neutral auxiliary ligands and 2-phenylpyridine or 2-(4'-fluoropheny1)-R-pyridines (where R is 4-methoxy, ...

2012

Blue Phosphorescence of Trifluoromethyl- and Trifluoromethoxy-Substituted Cationic Iridium(III) Isocyanide Complexes

Michael Graetzel, Mohammad Khaja Nazeeruddin, Rosario Scopelliti

We report the first comprehensive comparative synthetic, structural, electrochemical, and spectroscopic study of an extended series of fluorocarbon-modified iridium(III) complexes. We prepared seven new cationic Ir(III) complexes with tert-butyl isocyanide ...

American Chemical Society2012

Synthesis of authenticable halftone images with non-luminescent halftones illuminated by a luminescent emissive layer

Roger Hersch, Julien Alexandre Andres

A method and computing system are proposed for producing an authenticable security device with two sides. The verso side is covered with a luminescent emissive variable intensity layer formed for example by invisible luminescent ink halftones and the recto ...

2012

Near-UV to red-emitting charged bis-cyclometallated iridium(III) complexes for light-emitting electrochemical cells

Michael Graetzel, Mohammad Khaja Nazeeruddin, Davide Di Censo, Rosario Scopelliti

Herein we report a series of charged iridium complexes emitting from near-UV to red using carbene-based (NC)-C-boolean AND: ancillary ligands. Synthesis, photophysical and electrochemical properties of this series are described in detail together with X-ra ...

Royal Society of Chemistry2012

Photosensitivity and luminescence of chromium and bismuth doped fibers

Christian Ban

Optical fiber materials with broad-band gain in the visible or in the telecommunication window are of great interest for optical communication or the biomedical domain in order to built integrated tunable lasers, amplifiers, ultra-short pulse lasers, or br ...

EPFL2009

New Opportunities for Lanthanide Luminescence

Jean-Claude Bünzli, Caroline Vandevyver, Steve Comby, Anne-Sophie Chauvin

Trivalent lanthanide ions display fascinating optical properties. The discovery of the corresponding elements and their fist industrial uses were intimately linked to their optical properties. This relationship has been kept alive until today when many hig ...

2007

Single molecule detection and fluorescence correlation spectroscopy on surfaces

Kai Hassler

In this thesis a new approach for single molecule detection and analysis is explored. This approach is based on the combination of two well established methods, fluorescence correlation spectroscopy (FCS) and total internal reflection fluorescence microsco ...

EPFL2006