Nanotechnology Now





Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Development of a High-performance Photocatalyst that is Surface-treated with Cesium

Photo 1: New high-performance photocatalyst (upper left) and an overall model of the photocatalyst-electrolysis hybrid system
A photocatalytic reaction converting solar energy is used to lower the electrolysis voltage required for the hydrogen production by water electrolysis.
Photo 1: New high-performance photocatalyst (upper left) and an overall model of the photocatalyst-electrolysis hybrid system A photocatalytic reaction converting solar energy is used to lower the electrolysis voltage required for the hydrogen production by water electrolysis.

Abstract:
A step toward the realization of a new hydrogen production system using solar light

Development of a High-performance Photocatalyst that is Surface-treated with Cesium

Japan | Posted on May 17th, 2010

* The activity of a tungsten oxide photocatalyst was increased by surface treatment with cesium.
* The quantum yield of the new photocatalyst under visible light is larger than the previously reported values by a factor of about 50.
* The photocatalyst can reduce the voltage required for water electrolysis by almost 50%, thereby lowering the cost of hydrogen production.

Summary

Kazuhiro Sayama (Leader), Yugo Miseki (Research Scientist), et al. of Solar Light Energy Conversion Group, the Energy Technology Research Institute (Director: Yasuo Hasegawa) of the National Institute of Advanced Industrial Science and Technology (AIST; President: Tamotsu Nomakuchi), developed a tungsten oxide (WO3) photocatalyst (Upper left in photo 1) that provides a significantly higher quantum yield under visible light than conventional photocatalysts. A photocatalyst-electrolysis hybrid system (Photo 1) using this photocatalyst is a hydrogen production system in which solar light is efficiently used. The AIST's original system employs the photocatalyst that generates oxygen by oxidizing water and reducing iron(III) ions (Fe3+) to iron(II) ions (Fe2+). The system also involves low-voltage electrolysis in which water is reduced to generate hydrogen and Fe2+ ions are oxidized to Fe3+ ions.

The high efficiency of the WO3 photocatalyst was achieved using a new method—treatment of the surface of the photocatalyst with Cesium (Cs). The activity of the treated catalyst is more than ten times that of untreated catalysts. The quantum yield of the new photocatalyst is 19% under visible light of wavelength 420 nm and is approximately 50 times the previously reported values (0.4%)*. The use of solar energy can reduce the voltage required for water electrolysis by almost 50%. Hence, the low-cost production of hydrogen is expected.

The details of this technology will be presented on March 19, 2010 at the symposium organized by the Energy and Environment Study Group at the 57th Spring Meeting, 2010, of the Japan Society of Applied Physics to be held at Tokai University.

Social Background of Research

In order to suppress the emission of carbon dioxide and create a sustainable society, it is essential to make efficient use of renewable energy. One of the technologies for the effective use of solar energy, which is the most abundant renewable energy, is a low-cost hydrogen-production technique in which water is directly decomposed by photocatalysts to obtain hydrogen and oxygen. This technology has been actively studied as a fundamental technology for a future hydrogen-energy-based society. If a photocatalyst system which is as efficient as solar cells and as simple and inexpensive as plant cultivation is being developed, it can be expected to contribute significantly to the realization of a society that is not dependent on fossil resources. However, the quantum yield and solar-energy conversion efficiency of photocatalysts are still low at present. Consequently, the development of a high-performance photocatalyst system is desired.

History of Research

AIST has studied a photocatalyst-electrolysis hybrid system (Figs. 1 and 2) that can help overcome the disadvantages of conventional photocatalytic hydrogen production. This system can possibly enhance the efficiency of the photocatalyst. Further, it has the advantages of producing pure hydrogen and not requiring a large transparent hood for hydrogen collection. Because of decreased electrolysis voltage, we can also expect to manufacture hydrogen at a lower cost compared to ordinary water electrolysis systems. This system offers the advantages of conventional photocatalytic methods as well as those of usual electrolytic processes. While certain candidate redox media are used for oxidation-reduction reactions, the technique for low-voltage hydrogen production using Fe2+ ions has already been established. Consequently, the use of iron (Fe2+ and Fe3+ ion pairs) as the redox medium is, at present, the most practical technique for the hybrid system. Thus, another major challenge that was faced in the realization of this hybrid system was the development of a high-performance photocatalyst that would reduce the redox medium (from Fe3+ to Fe2+) while generating oxygen from water.

Read the details here www.aist.go.jp/aist_e/latest_research/2010/20100517/20100517.html

####

For more information, please click here

Copyright © AIST

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

Nanostructures Increase Corrosion Resistance in Metallic Body Implants May 24th, 2015

Iranian Scientists Use Magnetic Field to Transfer Anticancer Drug to Tumor Tissue May 24th, 2015

Basel physicists develop efficient method of signal transmission from nanocomponents May 23rd, 2015

This Slinky lookalike 'hyperlens' helps us see tiny objects: The photonics advancement could improve early cancer detection, nanoelectronics manufacturing and scientists' ability to observe single molecules May 23rd, 2015

Academic/Education

SUNY Poly CNSE and NIOSH Launch Federal Nano Health and Safety Consortium: May 20th, 2015

New JEOL E-Beam Lithography System to Enhance Quantum NanoFab Capabilities May 6th, 2015

FEI Partners With the George Washington University to Equip New Science & Engineering Hall: Suite of new high-performance microscopes will be used for cutting-edge experiments at GW’s new research facility April 29th, 2015

Renishaw Raman systems used to study 2D materials at Boston University, Massachusetts, USA. April 28th, 2015

Announcements

Nanostructures Increase Corrosion Resistance in Metallic Body Implants May 24th, 2015

Iranian Scientists Use Magnetic Field to Transfer Anticancer Drug to Tumor Tissue May 24th, 2015

Basel physicists develop efficient method of signal transmission from nanocomponents May 23rd, 2015

This Slinky lookalike 'hyperlens' helps us see tiny objects: The photonics advancement could improve early cancer detection, nanoelectronics manufacturing and scientists' ability to observe single molecules May 23rd, 2015

Energy

Visualizing How Radiation Bombardment Boosts Superconductivity: Atomic-level flyovers show how impact sites of high-energy ions pin potentially disruptive vortices to keep high-current superconductivity flowing May 23rd, 2015

Conversion of Greenhouse Gases to Syngas in Presence of Nanocatalysts in Iran May 22nd, 2015

Sandia researchers first to measure thermoelectric behavior by 'Tinkertoy' materials May 20th, 2015

Industrial Nanotech, Inc. Announces Official Launch of the Eagle Platinum Tile™ May 19th, 2015

Solar/Photovoltaic

Efficiency record for black silicon solar cells jumps to 22.1 percent: Aalto University's researchers improved their previous record by over 3 absolute percents in cooperation with Universitat Politècnica de Catalunya May 18th, 2015

Wearables may get boost from boron-infused graphene: Rice U. researchers flex muscle of laser-written microsupercapacitors May 18th, 2015

Random nanowire configurations increase conductivity over heavily ordered configurations May 16th, 2015

ORNL demonstrates first large-scale graphene fabrication May 14th, 2015

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More










ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project