Ecole Polytechnique Federale De Lausanne

Heliatek Gmbh

Universitat Ulm

Universitaet Ulm

Peter Bäuerle

Michael Graetzel

Karl Leo

Martin Pfeiffer

Shaik Mohammed Zakeeruddin

Gunter Mattersteig

Dirk Hildebrandt

Olga Gerdes

Andre Weiss

Christian Uhrich

Daniel D'Souza

Roland Fitzner

Eduard Brier

Michael Bauer

Yuhang Liu

Annette Petrich

Rico Schüppel

Kerstin Schulze

Egon Reinold

Hannelore Kast

Amaresh Mishra

Astrid Vogt

Christoph Wenzel

Christopher Steck

Popovic Dusko

The organic small molecule 4,4',4&#x2033;,4&#x2032;&#x2033;-(5,5-dimethoxycyclopenta-1,3-diene-1,2,3,4-tetrayl)tetrakis(N,N-bis(4-methoxyhenyl)aniline (CPDA 1), shows electrochemical properties very close to spiro-OMeTAD indicating a high compatibility with PSC systems for its use as a hole transport material (HTM). The implementation of the cyclopentadiene dimethyl acetale core helps to red shift the absorption onset of the films as well as provide a flexible spatial configuration of the molecule, which is essential for optimum film forming properties. Transient and steady state emission analysis as well as hole mobility measurements indicate that the new HTM allows a better charge extraction, transport and separation than the spiro-OMeTAD reference compound. PSCs based on the new CPDA 1 show a PCE close to 23% with lower hysteresis than its analogue. Stability studies performed under ambient, heated and humid conditions all showed that CPDA 1 is over-performing spiro-OMeTAD. Furthermore the production cost of CPDA 1 is about 10 times lower than that of spiro-OMeTAD, contributing to render PSCs more affordable.

Hole transport material, synthesis thereof, and solar cell

The invention relates to an organic photoactive device, especially an organic photovoltaic cell, with a contact and a countercontact as well as with an organic region that is electrically connected to the contact and the countercontact, wherein a photoactive region with a photoactive bulk heterojunction or a flat heterojunction between an electron-conducting organic material and a hole-conducting organic material is formed in the organic region and wherein the hole-conducting organic material and/or the electron-conducting organic material is formed from oligomers according to any one of the following types: conjugated acceptor-donor-acceptor oligomer (A-D-A' oligomer) with an acceptor unit (A) and a further acceptor unit (A&#x2032;) that are each connected to a donor unit (D), and conjugated donor-acceptor-donor oligomer (D-A-D&#x2032; oligomer) with a donor unit (D) and a further donor unit (D&#x2032;) that are each connected to an acceptor unit (A).

Organic photoactive device

Growing community of inventors

Elchingen, Germany

Peter Bäuerle