Keywords: energy (310) solar energy (245) HZB own research (99)

Science Highlight    23.11.2018

Molecules that self-assemble into monolayers for efficient perovskite solar cells

The molecule organises itself on the electrode surface until a dense, uniform monolayer is formed.
Copyright: Saule Magomedoviene / HZB

“Self‐Assembled Hole Transporting Monolayer for Highly Efficient Perovskite Solar Cells”. Cover of current issue of Advanced Energy Materials.
Copyright: Wiley/VCH

A team at the HZB has discovered a new method for producing efficient contact layers in perovskite solar cells. It is based on molecules that organise themselves into a monolayer. The study was published in Advanced Energy Materials and appeared on the front cover of the journal.

In recent years, solar cells based on metal halide perovskites have achieved an exceptional increase in efficiency. These materials promise cost-effective and flexible solar cells, and can be combined with conventional PV materials such as silicon to form particularly efficient tandem solar cells. An important step towards mass production is the development of efficient electrical contact layers that would allow deposition of perovskite layers on various substrates.

Molecules form monolayer

Now the HZB Young Investigator Group headed by physicist Dr. Steve Albrecht, in collaboration with former DAAD exchange student Artiom Magomedov from Kaunas University of Technology (KTU) in Lithuania, has synthesized a novel molecule that self-assembles into a monolayer (SAM). The team successfully used this new material as a hole-conducting layer in perovskite solar cells. The molecule is carbazole-based and bonds to the oxide of the transparent electrode via a phosphonic acid anchoring group. Due to the anchoring fragment, this molecule organises itself on the electrode surface until a dense, uniform monolayer is formed. The ultra-thin layer exhibits no optical losses and, thanks to its self-organising property, could conformally cover any surface – including textured silicon in tandem solar-cell architectures.

Adaption possible

Extremely low material consumption is achieved with this technique, and the chemical structure of the SAMs can be adapted to the desired application. Thus, SAMs could also serve as a model system for future investigations of the properties of perovskite interfaces and growth.

New generation to be developed at HySPRINT Lab

The work took place at the HySPRINT laboratory of the HZB where Albrecht's group is now conducting research on a new generation of self-assembling molecules, which already enable solar cells with efficiencies of over 21 %.

Patent application filed

Since this approach to perovskite solar cells has never been considered before and can potentially play a role in industrial processes, the HZB and KTU teams have filed a patent application on the molecule and its use. As the scientific interest for this new contact material class is enormous, the journal has displayed an illustration from the paper on the front cover of the current issue.

Published in Advanced Energy Materials 2018: “Self‐Assembled Hole Transporting Monolayer for Highly Efficient Perovskite Solar Cells”. Artiom Magomedov, Amran Al‐Ashouri, Ernestas Kasparavičius, Simona Strazdaite, Gediminas Niaura, Marko Jošt, Tadas Malinauskas, Steve Albrecht and Vytautas Getautis.

Doi: 10.1002/aenm.201870139

Autor: Amran Al Ashouri, PhD student and shared first author of the publication


           



You might also be interested in
  • <p>HZB-Teams are exploring and developing new technologies for perovskite based solar cells in the innovation lab HySPRINT.</p>NEWS      16.05.2019

    LAUNCH OF EPKI: European Perovskite Initiative for the development of Perovskite based solar technology

    Perovskite based solar cells have made tremendous progress over the last decade achieving lab-scale efficiencies of 24.2% early 2019 in single-junction architecture and up to 28% in tandem (perovskite associated with crystalline silicon), turning it into the fastest-advancing solar technology to date. With the HySPRINT project and the recruitment of highly talented young scientists, Helmholtz-Zentrum Berlin has built up a considerable research capacity in the field of perovskite materials in recent years and is participating in the European Perovskite Initiative EPKI that has now been launched. [...]


  • NEWS      15.05.2019

    The HZB at INTERSOLAR in Munich

    The Helmholtz-Zentrum Berlin (HZB) will present itself from 15 to 17 May at INTERSOLAR in Munich, the world's largest solar trade fair. The HZB is one of the world's leading research centres in the field of solar energy and presents the latest developments in photovoltaics and solar fuels. The HZB offers a wide range of cooperation opportunities for companies - from contract research to joint research projects. [...]


  • NEWS      14.05.2019

    Bernd Stannowski is Professor at the Beuth University of Applied Sciences Berlin

    Prof. Dr. Bernd Stannowski has received and accepted a call for a joint S-Professorship for "Photovoltaics" at the Beuth University of Applied Sciences Berlin. The physicist heads the working group "Silicon Photovoltaics" at the Competence Center Thin Film and Nanotechnology for Photovoltaics Berlin (PVcomB) of the HZB. [...]




Newsletter