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Concept

Photosensitizer

Publications associées (32)

Plasmonic Nanostructures for Photocatalysis: Material, Photonic and Electronic Effects

Fateme Kiani Shahvandi

Plasmonic photochemistry has a large potential to replace energy-intensive chemical processes with low-temperature, low-pressure light-driven chemical reactions. Plasmonic nanostructures have emerged as promising photocatalysts with exceptional and tunable ...

EPFL2024

Impact of chlorination and ozonation of dissolved organic matter on its photo-induced production of long-lived photooxidants and excited triplet states

Urs von Gunten, Stephanie Christa Remke, Joanna Maria Houska

Recent studies suggested that long-lived photooxidants (LLPO), which are reactive intermediates formed during irradiation of dissolved organic matter (DOM), may consist of phenoxyl radicals derived from phenolic moieties of the DOM. Besides the well-studie ...

PERGAMON-ELSEVIER SCIENCE LTD2023

Symmetry and Rigidity for Boosting Erbium-Based Molecular Light-Upconversion in Solution

Jean-Claude Bünzli

Previously limited to highly symmetrical homoleptic triple-helical complexes [Er(Lk)3]3+, where Lk are polyaromatic tridentate ligands, single-center molecular-based upconversion using linear optics and exploiting the excited-state absorption mechanism (ES ...

Wiley-VCH Verlag GmbH2023

Symmetry-Induced Singlet-Triplet Inversions in Non-Alternant Hydrocarbons

Anne-Clémence Corminboeuf, Jacob Terence Blaskovits, Marc Hamilton Folkmann Garner

Molecules with inversion of the singlet and triplet excited-state energies are highly promising for the development of organic light-emitting diodes (OLEDs). To date, azaphenalenes are the only class of molecules where these inversions have been identified ...

Wiley-VCH Verlag GmbH2023

Selectively Exciting and Probing Radiative Plasmon Modes on Short Gold Nanorods by Scanning Tunneling Microscope-Induced Light Emission

Olivier Martin

We study the plasmon modes of gold nanorods (as short as similar to 100 nm) on a nonmetallic conductive substrate using scanning tunneling microscope-induced light emission (STM-LE) with a nonplasmonic tungsten tip at room temperature in high vacuum (10-7 ...

AMER CHEMICAL SOC2023

Photochemical oxidation of phenols and anilines mediated by phenoxyl radicals in aqueous solution

Urs von Gunten, Stephanie Christa Remke

Reactive intermediates formed upon irradiation of chromophoric dissolved organic matter (CDOM) contribute to the degradation of various organic contaminants in surface waters. Besides well-studied "short-lived" photo oxidants, such as triplet state CDOM (3 ...

PERGAMON-ELSEVIER SCIENCE LTD2022

Donor-Acceptor-Donor "Hot Exciton" Triads for High Reverse Intersystem Crossing in OLEDs

Anne-Clémence Corminboeuf, Sergio Vela Llausi, Maria Fumanal Quintana

Hot exciton materials have the potential to improve the quantum efficiency of organic light-emitting diodes (OLEDs) by promoting high reversed intersystem crossing (hRISC) between a high-lying triplet (T-n, n >= 2) and a radiative singlet (S-m). In recent ...

WILEY-V C H VERLAG GMBH2022

Phototransformation of Organic Contaminants in Aquatic Systems: Characterization of Long-Lived Photooxidants Derived from Dissolved Organic Matter

Stephanie Christa Remke

The increasing interest in the fate of organic contaminants in the aquatic environment requires the elucidation of relevant abiotic transformation processes. These processes often involve the ubiquitous dissolved organic matter (DOM), a complex mixture of ...

EPFL2021

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

Block Copolymer Stabilized Liquid Nanodroplets Facilitate Efficient Triplet Fusion-Based Photon Upconversion in Solid Polymer Matrices

Felipe Andres Saenz Padilla

Sensitized triplet-triplet annihilation-based photon upconversion is a photo-physical process that affords anti-Stokes-shifted emission after annihilation of two metastable triplet excitons of an emitter dye and the formation of a fluorescent singlet state ...

AMER CHEMICAL SOC2021

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

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

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

Copper(I) Based Photoredox Chemistry

Murat Alkan

Photoredox catalysis has become a powerful tool for chemists. However, the reliance on expensive Ir and Ru based photoredox catalysts (PC) motivates research for more sustainable options. Copper complexes based on favorable photophysical properties, high a ...

EPFL2020

Catechin reduces phototoxic effects induced by protoporphyrin IX-based photodynamic therapy in the chick embryo chorioallantoic membrane

Georges Wagnières, Jaroslava Joniová

Significance: Side effects of many cancer treatments are associated with the production of reactive oxygen species (ROS) in normal tissues. This explains why patients treated by photodynamic therapy (PDT) often suffer from skin photosensitization, whereas ...

SPIE Society of Photo-optical Instrumentation Engineers2020

Mixed scalar-current bootstrap in three dimensions

Alessandro Vichi, Marten Jan Reehorst

We study the mixed system of correlation functions involving a scalar field charged under a global U(1) symmetry and the associated conserved spin-1 current J(mu). Using numerical bootstrap techniques we obtain bounds on new observables not accessible in t ...

Springer Nature2020

Photoprotective effect of catechin during ALA-PDT

Georges Wagnières, Jaroslava Joniová

The production of reactive oxygen species (ROS) in normal tissues is associated with side effects of many cancer treatments. This is, in particular, the case for the skin photosensitization experienced by certain patients subjected to PDT based on a system ...

SPIE-INT SOC OPTICAL ENGINEERING2019

Laser flash photolysis study of the photoinduced oxidation of 4-(dimethylamino)benzonitrile (DMABN)

Urs von Gunten, Frank Jonathan Leresche

Aromatic amines are aquatic contaminants for which phototransformation in surface waters can be induced by excited triplet states of dissolved organic matter ((DOM)-D-3*). The first reaction step is assumed to consist of a one-electron oxidation process of ...

ROYAL SOC CHEMISTRY2019

Photoredox-Catalyzed Decarboxylation for the Transfer of Alkynes and Nitriles Using Hypervalent Iodine Reagents

Franck Le Vaillant

Aliphatic alkynes and nitriles are privileged motifs in organic chemistry. Therefore, alkynes and nitriles have played a central role for the exploration and development of novel strategies to forge C-C bonds in efficient manner. They are broadly used as v ...

EPFL2019

Blocking the Charge Recombination with Diiodide Radicals by TiO2 Compact Layer in Dye-Sensitized Solar Cells

Ulf Anders Hagfeldt, Nikolaos Vlachopoulos, Kazuteru Nonomura

The addition of a compact titanium dioxide (TiO2) layer between the fluorine-doped tin oxide (FTO) coated glass substrate and the mesoporous TiO2 layer in the dye-sensitized solar cell (DSC) based on the iodide/triiodide redox couple (I-/I-3(-)) is known t ...

ELECTROCHEMICAL SOC INC2019

Efficient intersystem crossing in 2-aminopurine riboside probed by femtosecond time-resolved transient vibrational absorption spectroscopy

Rebecca Ann Ingle, Hugo Jean Baptiste Marroux

The photophysical dynamics of 2-aminopurine riboside (2APr) in CHCl3 have been studied following excitation at (pump) = 310 nm by means of femtosecond transient vibrational absorption spectroscopy (TVAS) aided by quantum chemical density functional theory ...

ROYAL SOC CHEMISTRY2018

Photophysical Heavy-Atom Effect in Iodinated Metallocorroles: Spin-Orbit Coupling and Density of States

Majed Chergui, Enrico Pomarico, Marine Eva Fedora Bouduban

Excited-state dynamics and electronic structures of Al and Ga corrole complexes were studied as a function of the number of beta-pyrrole iodine substituents. Using spectrally broad-band femtosecond-resolved fluorescence upconversion, we determined the kine ...

AMER CHEMICAL SOC2018