Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

High Durability and Efficiency of 1 cm2 Size Perovskite Solar Cells

16.11.2015

A research group led by National Institute for Materials Science, Japan, improved the power conversion efficiency of perovskite solar cells to over 16% while employing cells that were greater than 1 cm2.

The cells have passed 1,000 Hours of Light Soaking (AM 1.5G, 100 mW/cm2) test, which is considered to be a basic criterion for practical use. These achievements were made by replacing the conventional organic materials with heavily doped inorganic metal oxide materials as the electron and hole extraction layers of the cells.


Distribution of power conversion efficiencies (PCEs) obtained from the perovskite solar cells fabricated by the research group.

Copyright : NIMS


Results of continuous exposure of perovskite solar cells to solar light (light intensity: 100 mW/cm2). The black line represents cells that were not exposed to light while the red line represents cells that were exposed to light.

Copyright : NIMS

A research group led by Dr. Liyuan Han, Director of the Photovoltaic Materials Unit, National Institute for Materials Science (NIMS), Japan, improved the power conversion efficiency (PCE) of perovskite solar cells to over 16% while employing cells that were greater than 1 cm2.

The high efficiency cells also passed the durability test (exposure to AM 1.5G 100 mW/cm2 sunlight for 1,000 hours), which is considered to be a basic criterion for practical use. These achievements were made by replacing the conventional organic materials with inorganic materials as the electron and hole extraction layers of the solar cells.

There are high expectations for perovskite solar cells as they may be produced at lower cost than silicon solar cells. However, high efficiency perovskite solar cells have often been reached with poor stability and small area typically less than 0.1 cm2.

As such a small device size is prone to induce measurement errors, an obligatory minimum cell area of >1 cm2 is required for certified PCEs to be recorded in the standard “Solar Cell Efficiency Tables” that allows the comparison of competing technologies. Therefore, in order to realize practical use of perovskite solar cells, it is urgent to conduct studies using larger cells and attain more reliable PCEs.

To solve these issues, the research group first replaced the conventional organic materials with robust inorganic materials for use in electron and hole extraction layers. Because these layers fabricated with inorganic metal oxide materials have high electrical resistance, it was necessary to reduce the thickness of the layers to several nanometers (nm).

However, as the area of these thin layers increases, the occurrence of defects called pinholes also increases, leading to decreased PCEs. To deal with this problem, the research group increased the electrical conductivity of these layers by more than 10 times through heavily doping in both electron and hole extraction layers.

In this way, the group successfully fabricated layers that have fewer pinholes over wide areas and are applicable at thicknesses of up to 10 to 20 nm. Using these layers, a PCE of 16% was repeatedly attained while employing cells that were greater than 1 cm2.

Furthermore, the use of inorganic materials both in electron and hole extraction layers contributed to the control of PCE reduction within 10% even after undergoing 1,000 hours of continuous exposure to sunlight at an intensity of 1 sun, demonstrating outstanding reliability.

Based on these results, the group aims to develop more efficient light absorbing material capable of utilizing a greater amount of sunlight and precisely control the interfaces in the devices, for achieving higher PCEs and stability.

This study was conducted under the research topic “Device physics of dye-sensitized solar cells” in the research area “Creative research for clean energy generation using solar energy (research supervisor: Masafumi Yamaguchi, Principal Professor, Toyota Technological Institute)” as part of the Strategic Basic Research Programs (specifically the CREST program) sponsored by the Japan Science and Technology Agency (JST). The study was published in the online version of Science on October 29, 2015.

(This study was published in the online version of Science on October 29, 2015: W. Chen, Y. Wu, Y. Yue, J. Liu, W. Zhang, X. Yang, H. Chen, E. Bi, A. Islam, M. Gratzel and L. Han: Efficient and stable large-area perovskite solar cells with inorganic charge-extraction layers [DOI: 10.1126/science.aad1015]).

Associated links
Original article from NIMS

Mikiko Tanifuji | Research SEA
Further information:
http://www.researchsea.com

More articles from Materials Sciences:

nachricht Physics, photosynthesis and solar cells
01.12.2016 | University of California - Riverside

nachricht New process produces hydrogen at much lower temperature
01.12.2016 | Waseda University

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

Im Focus: Fraunhofer ISE Develops Highly Compact, High Frequency DC/DC Converter for Aviation

The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.

Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

UTSA study describes new minimally invasive device to treat cancer and other illnesses

02.12.2016 | Medical Engineering

Plasma-zapping process could yield trans fat-free soybean oil product

02.12.2016 | Agricultural and Forestry Science

What do Netflix, Google and planetary systems have in common?

02.12.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>