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 New design improves performance of flexible wearable electronics
23.06.2017 | North Carolina State University

nachricht Plant inspiration could lead to flexible electronics
22.06.2017 | American Chemical Society

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Touch Displays WAY-AX and WAY-DX by WayCon

27.06.2017 | Power and Electrical Engineering

Drones that drive

27.06.2017 | Information Technology

Ultra-compact phase modulators based on graphene plasmons

27.06.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>