Publications associées à Photocatalysis with organic dyes: facile access to reactive intermediates for synthesis

Development of remote C-H bond functionalization of redox-active alcohol derivatives and oxidative transformations under photoredox catalysis

The development of radical-based remote C(sp3)-H functionalizations of redox-active alcohol derivatives, oxidative cycloaddition and rearrangement transformations under visible light photocatalysis constitute the basis of this thesis. The first chapter des ...

EPFL2021

Coupled As and Mn Redox Transformations in an Fe(0) Electrocoagulation System: Competition for Reactive Oxidants and Sorption Sites

Sachiko Hirosue, Jasquelin Peña, Nathalie Manetti, Victor Carle Adrien Boureau

Iron electrocoagulation (EC) can be used for the decentralized treatment of arsenic(As)-contaminated groundwater. Iron EC involves the electrolytic dissolution of an Fe(0) electrode to Fe(II). This process produces reactive oxidants, which oxidize As(III) ...

AMER CHEMICAL SOC2020

Investigations of the Chemistry of 1-Alkynyltriazenes

Florian Gérald Abela

The chemistry of aromatic triazenes is well known, and has been explored for more than a century. These compounds have emerged as very useful intermediates, because of their unique reactivity. This functionality can notably be used to access many other fun ...

EPFL2018

Significance of pi-bridge contribution in pyrido[3,4-b]pyrazine featured D-A-pi-A organic dyes for dye-sensitized solar cells

Michael Graetzel, Shaik Mohammed Zakeeruddin, Yelin Hu, Fabrizio Giordano, Xiaoyu Zhang, Zhongjin Shen

The 3,4-ethylenedioxythiophene (EDOT) pi-bridge is one of the most commonly used building blocks for sensitizers in dye-sensitized solar cells (DSSCs). We investigated its influence on the molecular structure, the photophysical and electrochemical properti ...

Chinese Chemical Soc2017

Novel Blue Organic Dye for Dye-Sensitized Solar Cells Achieving High Efficiency in Cobalt-Based Electrolytes and by Co-Sensitization

Michael Graetzel, Shaik Mohammed Zakeeruddin, Ulf Anders Hagfeldt, Yasemin Saygili, Kazuteru Nonomura, Enrico Polanski, Anna Eriksson, Jiahuan Zhang, Yan Hao

Blue and green dyes as well as NIR-absorbing dyes have attracted great interest because of their excellent ability of absorbing the incident photons in the red and near-infrared range region. A novel blue D-pi-A dye (Dyenamo Blue), based on the diketopyrro ...

2016

A study of oligothiophene-acceptor dyes in p-type dye-sensitized solar cells

Ulf Anders Hagfeldt, Peng Liu, Lei Zhang

Two new dyes, E1 and E2, equipped with triphenylamine as the electron donor, oligothiophene as the linker and different electron acceptor groups, have been designed and synthesized as photosensitizers for p-type dye-sensitized solar cells (p-DSCs). A syste ...

Royal Soc Chemistry2016

Unraveling the Dual Character of Sulfur Atoms on Sensitizers in Dye-Sensitized Solar Cells

Jacques-Edouard Moser, Mohammad Khaja Nazeeruddin, Joël Teuscher, Thomas Moehl, Aswani Yella, Peng Gao, Sadig Aghazada

Cyclometalated ruthenium sensitizers have been synthesized that differ with number of thiophene units on the auxiliary ligands. Sensitizers possessing four (SA25, SA246, and SA285) or none (SA282) sulfur atoms in their structures, were tested in solar cell ...

Amer Chemical Soc2016

Synthetic chemistry with nitrous oxide

Kay Severin

This review article summarizes efforts to use nitrous oxide (N2O, ‘laughing gas’) as a reagent in synthetic chemistry. The focus will be on reactions which are carried out in homogeneous solution under (relatively) mild conditions. First, the utilization o ...

Royal Society of Chemistry2015

Influence of Dye Architecture of Triphenylamine Based Organic Dyes on the Kinetics in Dye-Sensitized Solar Cells

Ulf Anders Hagfeldt, Gunther Wittstock

The impact of the dye architecture on the kinetics in the dyesensitized solar cell (DSC) was investigated for two structurally similar organic dyes, adsorbed adsorbed to a mesoporous TiO2 film. Differences in the HOMO and LUMO levels of the triphenylamine ...

American Chemical Society2015

Molecular Engineering of Pyrido[3,4-b]pyrazine-Based Donor-Acceptor-pi- Acceptor Organic Sensitizers: Effect of Auxiliary Acceptor in Cobalt- and Iodine-Based Electrolytes

Michael Graetzel, Shaik Mohammed Zakeeruddin, Jean-David Décoppet, Fabrizio Giordano, Bo Liu

Due to the ease of tuning its redox potential, the cobalt-based redox couple has been extensively applied for highly efficient dye-sensitized solar cells (DSSCs) with extraordinarily high photovoltages. However, a cobalt electrolyte needs particular struct ...

Wiley-Blackwell2015

Synthesis and Reactivity of Mononuclear Iron Models of [Fe]-Hydrogenase that Contain an Acylmethylpyridinol Ligand

Xile Hu, Dafa Chen, Bowen Hu

[Fe]-hydrogenase has a single iron-containing active site that features an acylmethylpyridinol ligand. This unique ligand environment had yet to be reproduced in synthetic models; however the synthesis and reactivity of a new class of small molecule mimics ...

Wiley-V C H Verlag Gmbh2014

The cysteine desulfurase IscS of Mycobacterium tuberculosis is involved in iron sulfur cluster biogenesis and oxidative stress defence

Gaëlle Séraphine Kolly, Stewart Cole, Florence Pojer, Jeffrey Chen, Jan Lars Rybniker

The complex multiprotein systems for the assembly of protein-bound iron sulfur (Fe S) clusters are well defined in Gram-negative model organisms. However, little is known about Fe S cluster biogenesis in other bacterial species. The ISC (iron sulfur cluste ...

Portland Press2014

Molecular Engineering of Organic Dyes for Improved Recombination Lifetime in Solid-State Dye-Sensitized Solar Cells

Michael Graetzel, Thomas Moehl, Julian Burschka

A major limitation of solid-state dye-sensitized solar cells is a short electron diffusion length, which is due to fast recombination between electrons in the TiO2 electron-transporting layer and holes in the 2,2',7,7'-tetrakis(N,N-di-p-methoxyphenylamine) ...

American Chemical Society2013

Fine-tuning the Electronic Structure of Organic Dyes for Dye-Sensitized Solar Cells

Michael Graetzel, Mohammad Khaja Nazeeruddin, Hoi Nok Tsao, Peng Gao

A series of metal-free organic dyes exploiting different combinations of (hetero)cyclic linkers (benzene, thiophene, and thiazole) and bridges (4H-cyclopenta[2,1-b:3,4-b']dithiophene (CPDT) and benzodithiophene (BDT)) as the central pi-spacers were synthes ...

American Chemical Society2012

Kinetic and Mechanistic Investigations of the Oxidation of Tramadol by Ferrate and Ozone

Urs von Gunten, Saskia Gisela Zimmermann-Steffens

The kinetics and oxidation products (OPs) of tramadol (TRA), an opioid, were investigated for its oxidation with ferrate (Fe(VI)) and ozone (O-3). The kinetics could be explained by the speciation of the tertiary amine moiety of TRA, with apparent second-o ...

2012

Multicolor Single Molecule Tracking of Stochastically Active Synthetic Dyes

Julia Gunzenhäuser, Suliana Manley, Aleksandr Benke

Single particle tracking can reveal dynamic information at the scale of single molecules in living cells but thus far has been limited either in the range of potential protein targets or in the quality and number of tracks attainable. We demonstrate a new ...

American Chemical Society2012

Influence of Donor Groups of Organic D-pi-A Dyes on Open-Circuit Voltage in Solid-State Dye-Sensitized Solar Cells

Michael Graetzel, Mohammad Khaja Nazeeruddin, Thomas Moehl, Chenyi Yi, Amalie Dualeh, Filippo de Angelis

In solid-state dye-sensitized solar cells (ssDSCs), the poor pore filling of the mesoporous semiconductor and the short diffusion length of charge carriers, in the hole-transport material (HTM) have limited the mesoscopic titania layer to a thickness of 2- ...

American Chemical Society2012

Design and Development of Functionalized Cyclometalated Ruthenium Chromophores for Light-Harvesting Applications

Michael Graetzel, Mohammad Khaja Nazeeruddin, Thomas Baumgartner, Aswani Yella

The syntheses and the electrochemical spectroscopic properties of a suite of asymmetrical bistridentate cyclometalated Ru(II) complexes bearing terminal triphenylamine (TPA) substituents are reported. These complexes, which contain structural design elemen ...

2011

Dynamics of Electron Transfer Processes at the Surface of Dye-Sensitized Mesoporous Semiconductor Films

Joël Teuscher

Electron transfer reactions taking place at the surface of dye-sensitized semiconductors are key processes in dye-sensitized solar cells (DSSCs). After light absorption, the excited state of a dye injects an electron into a wide-bandgap semiconductor, usua ...

EPFL2010

Chemical probes shed light on fusion proteins

Kai Johnsson

Site-specific protein labeling with synthetic dyes is an emerging technique for live cell imaging. A protein or peptide tag fused to the protein of interest provides the means for attachment of a fluorophore or other small molecule probe, to allow non-inva ...

2007