Thomas Wesley Holcombe

À propos de ce résultat

Cette page est générée automatiquement et peut contenir des informations qui ne sont pas correctes, complètes, à jour ou pertinentes par rapport à votre recherche. Il en va de même pour toutes les autres pages de ce site. Veillez à vérifier les informations auprès des sources officielles de l'EPFL.

Unités associées (2)

Laboratoire de photonique et interfaces

Participants aux cours CL

Cours enseignés par cette personne

Aucun résultat

Domaines de recherche associés (5)

Cellule solaire à pigment photosensible

Une cellule solaire à pigment photosensible parfois appelée cellules Grätzel (en anglais, Dye-sensitized solar cell ou DSC) est un système photoélectrochimique inspiré de la photosynthèse végétale

Efficacité énergétique (thermodynamique)

En physique et ingénierie mécanique, l'efficacité énergétique (ou efficacité thermodynamique) est un nombre sans dimension, qui est le rapport entre ce qui peut être récupéré utilement de la machine

Énergie solaire photovoltaïque

L'énergie solaire photovoltaïque (ou énergie photovoltaïque ou EPV) est une énergie électrique produite à partir du rayonnement solaire grâce à des capteurs ou à des centrales solaires photovoltaïqu

Afficher plus

Publications associées (11)

Publications associées

Chargement

Personnes menant des recherches similaires (98)

Personnes menant des recherches similaires

Chargement

Efficient Blue-Colored Solid-State Dye-Sensitized Solar Cells: Enhanced Charge Collection by Using an in Situ Photoelectrochemically Generated Conducting Polymer Hole Conductor

Michael Graetzel, Ulf Anders Hagfeldt, Thomas Wesley Holcombe, Nikolaos Vlachopoulos, Jiahuan Zhang

A high power conversion efficiency (PCE) of 5.5% was achieved by efficiently incorporating a diketopyrrolopyrrole-based dye with a conducting polymer poly(3,4-ethylenediothiophene) (PEDOT) hole-transporting material (HTM) that was formed in situ, compared with a PCE of 2.9% for small molecular spiroOMeTAD-based solid-state dye solar cells (sDSCs). The high PCE for PEDOT-based sDSCs is mainly attributed to the significantly enhanced charge-collection efficiency, as a result of the three-order-of-magnitude higher hole conductivity (0.53 Scm(-1)) compared with that of the widely used low molecular weight HTM spiro-OMeTAD (3.5 x 10(-4) Scm(-1)).

Wiley-V C H Verlag Gmbh2016

Chargement

Diketopyrrolopyrole (dpp)-based sensitizers for electrochemical or optoelectronic devices

Michael Graetzel, Thomas Wesley Holcombe, Mohammad Khaja Nazeeruddin, Jun Ho Yum

The present invention relates to compounds of formula (I) based on DPP moiety being useful as metal-free organic sensitizers or dyes of type D-Pi-A in electrochemical or optoelectronic devices, their use as sensitizer or dye and an electrochemical or optoelectronic device comprising a compound of the invention.

2015

Chargement

Unravel the Impact of Anchoring Groups on the Photovoltaic Performances of Diketopyrrolopyrrole Sensitizers for Dye-Sensitized Solar Cells

Paramaguru Ganesan, Peng Gao, Michael Graetzel, Thomas Wesley Holcombe, Mohammad Khaja Nazeeruddin, Aswani Yella

Two D-pi-A dyes, one with a strong electron withdrawing cyanoacrylic acid DPP 20 and one with a weak acceptor carboxylic acid DPP 21 have been synthesized and characterized for their application in dye-sensitized solar cells. This allows us to understand the role of electron withdrawing strength of the acceptor anchoring groups on the optoelectronic properties of chromophoric pi spacer molecules, e.g., the diketopyrrolopyrrole (DPP) moiety. The low energy absorption maxima of DPP 20 is red-shifted by only 7 nm compared to DPP 21, implying a minimal role for the strong acceptor in the light harvesting properties of colored pi spacer molecules. Because of this small red shift, J(SC) of DPP 20 is marginally higher than that of DPP 21. However, because of the higher fill factor of DPP 21, the overall power conversion efficiency (PCE = 7.65%) is higher than that of DPP20 (7.34%). The data reveal that a weak acceptor is adequate to achieve good light harvesting as well as provide good photovoltaic efficiencies for colored pi spacer sensitizers.

Amer Chemical Soc2015

Chargement