Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

android tablet pc

Home > Press > Research and applications of iron oxide nanoparticles

Fig.1 Novel red-colored iron oxide
Fig.1 Novel red-colored iron oxide

From the mysteries of producing red colors in traditional Japanese Bizen stoneware to iron-oxidizing bacteria for lithium ion batteries, Professor Jun Takada is at the forefront of research on innovative iron oxide nanomaterials. This research is featured in the December issue of the Okayama University eBulletin:

Research and applications of iron oxide nanoparticles

Okayama, Japan | Posted on February 26th, 2014

Professor Jun Takada is at the Graduate School of Natural Science and Technology at Okayama University. "I spent thirty years investigating how craftsman were able to render the beautiful red colors in Bizen and Arita pottery," explains Takada. "This research revealed the important role of iron oxide particles for producing the colors. I am now working on innovative applications of nanometer scale iron oxide materials produced by 'iron-oxidizing bacteria'. I have made a transition from fine ceramics and Bizen stoneware to fuel cells and biotechnology!"

Bizen ware has a history of more than a thousand years. The pottery has distinctive 'hidasuki' or 'fire-marked' reddish-brown colors(Fig.1) and is produced using iron rich clay mined from rice fields in the Bizen area of Okayama Prefecture. Intriguingly, the red colors are rendered by wrapping straw around the stoneware and not by glazing. But why does the straw, which was originally used to separate pieces of stoneware in kilns, produce the red colors where the straw is in contact with the surface of the clay?

"Our research showed the Bizen clay had a high content of iron lesser concentrations of other elements including silicon, calcium, magnesium, and sodium," explains Takada. "The red patterns are produced by the precipitation of corundum (α-Al2O3) followed by the formation of hermatite (α-Fe2O3) around it during the cooling process."

More specifically, potassium in the straw reduces the melting point of the surface of the Bizen clay, which leads to the formation of an approximately 50 micrometer thick liquid in the surface of the hot clay, where the aforementioned reactions occur. Furthermore, the research identified the formation of sandwich like crystals of α-Fe2O3/α-Al2O3/α-Fe2O3 particles during the reaction in the slow cooling.

"The main outcome of the research was the importance of hematite in formation of the hidasuki-red patterns," says Takada. "We also found a relationship between the growth of hematite particles and the color of the resulting Bizen ware."

Takada and colleagues also produced so called Al-substituted hematite, where the substitution of Al suppressed grain growth of hematite and the tone color became stronger with increasing aluminum. They found that particles of about 100 nm produced yellowish red, and larger particles sizes led to red and eventually dark purple colors. This research finally enabled the researchers to produce hematite based powders that do not contain hazardous elements such as chrome or lead, and there by increases the range of applications of these materials, especially producing Aka-e decoration on the over glazed Arita ware.

Inspired by his research on hematite and iron oxide particles for producing red colors, Takada initiated new research on the preparation of nanostructure tubes and fibers of iron oxides—known as biogenous iron oxides (BIOX)(Fig.1)—produced by so-called iron-oxidizing bacteria. "The yellowish brown precipitate found in a groundwater spring is due to the presence of extracellular fibrous bundles produced by iron oxidizing bacteria such as Leptothrix ochracea," says Takada. "Our research shows that this otherwise useless looking material has some extremely important applications." Indeed, research by Takada on the physical properties of the BIOX matrix showed this iron oxide to have an amorphous state made of organic/inorganic hybrid structure of ~3 nm sized nanoparticles of a many different elements including carbon, phosphorous, silicon, and iron.

Important applications of BIOX include as an anode material of Li-ion batteries, catalysts, color pigmentation, and innovation based on this materials high affinity to human cells. "Our studies on the formation of BIOX show that extracellular secretion of bacterial polymers triggers deposition and binding of aquatic inorganics such as Fe, Si, and P, which results in the unique organic/inorganic hybrid," says Takada. "This low cost BIOX is an eco-friendly and nontoxic functional material with a wide range of applications, including producing fine ceramics and arts, which are the roots of this research."


T. Ema, et al, "Robust porphyrin catalysts immobilized on biogenous iron oxide for the repetitive conversions of epoxides and CO2 into cyclic carbonates", Green Chemistry, 15 , 2485, (2013)
H. Hashimoto, et al, "Nano-micrometer-architectural acidic silica preparaed from iron oxide of Leptothrix ochracea origin", Applied Materials & Interfaces, 5, 5194, (2013).
H. Ishihara, et al, "Initial parallel arrangement of extracellular fibrils holds a key for sheath frame construction by Leptothrix sp. strain OUMS1", Minerals, 3, 73, (2013).
H. Hashimoto, et al, "Preparation, microstructue, and color tone of microtubule material composed of hematite/amorphous-silicate nonocomposite from iron oxide of bacterial origin", Dyes and Pigments, 95, 639, (2012).
J. Takada and H. Hashimoto, "Characteristics of biogenous iron oxide microtubes formed by iron-oxidizing bacteria, Leptothrix ochracea" , Handbook of Metal Biotechnology, ed. by M. Ike et al, Pan Stanford Publishing, pp.139, (2012).
T. Suzuki et al, "Environmental microbiology: silicon and phosphorus linkage with iron via oxygen in the amorphous matrix of Gallionella ferruginea stalks", Applied and Environmental Microbiology, 78, 236 (2012).
K. Mandai et al, "Iron oxide-immobilized palladium catalyst for the solvent-free Suzuki-Miyaura coupling reaction", Tetrahedron Letters, 53, 329, (2012).
T. Ema et al, "Highly active lipase immobilized on biogenous iron oxide via an organic bridging group: the dramatic effect of the immobilization support on enzymatic function," Green Chemistry, 13, 3187 (2011).
M. Furutani et al, "Initial assemblage of bacterial saccharic fibrils and element deposition to form an immature sheath in cultured Leptothrix sp. strain OUMS1", Minerals, 1, 157, (2011).
T. Sakai et al, "Chemical modification of biogenous iron oxide to create an excellent enzyme scaffold," Organic Biomolecular Chemistry, 8, 336 (2010).
Y. Kusano, et al, "Science in the art of the master Bizen potter", Accounts of Chemical Research, 43, 906, (2010).
H. Asaoka, et al, "Reproduction of Japanese traditional pigment based on iron oxide powders with yellowish red color", Materials Research Society Symposium Proceedings, 712, 435, (2002).


About Okayama University
Okayama University is one of the largest comprehensive universities in Japan with roots going back to the Medical Training Place sponsored by the Lord of Okayama and established in 1870. Now with 1,300 faculty and 14,000 students, the University offers courses in specialties ranging from medicine and pharmacy to humanities and physical sciences. Okayama University is located in the heart of Japan approximately 3 hours west of Tokyo by Shinkansen.

For more information, please click here

Okayama University
1-1-1 Tsushima-naka , Kita-ku ,
Okayama 700-8530, Japan
Planning and Public Information Division

Copyright © Okayama University

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.

Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

NanoScience: Giants of the Infinitesimal July 31st, 2014

University of Manchester selects Anasys AFM-IR for coatings and corrosion research July 30th, 2014

Nature inspires a greener way to make colorful plastics July 30th, 2014

Analytical solutions from Malvern Instruments support University of Wisconsin-Milwaukee researchers in understanding environmental effects of nanomaterials July 30th, 2014


New imaging agent provides better picture of the gut July 30th, 2014

Watching Schrödinger's cat die (or come to life): Steering quantum evolution & using probes to conduct continuous error correction in quantum computers July 30th, 2014

From Narrow to Broad July 30th, 2014

A new way to make microstructured surfaces: Method can produce strong, lightweight materials with specific surface properties July 29th, 2014


From Narrow to Broad July 30th, 2014

Nature inspires a greener way to make colorful plastics July 30th, 2014

Tough foam from tiny sheets: Rice University lab uses atom-thick materials to make ultralight foam July 29th, 2014

A new way to make microstructured surfaces: Method can produce strong, lightweight materials with specific surface properties July 29th, 2014


NanoScience: Giants of the Infinitesimal July 31st, 2014

Nature inspires a greener way to make colorful plastics July 30th, 2014

Analytical solutions from Malvern Instruments support University of Wisconsin-Milwaukee researchers in understanding environmental effects of nanomaterials July 30th, 2014

FEI Unveils New Solutions for Faster Time-to-Analysis in Metals Research July 30th, 2014


From Narrow to Broad July 30th, 2014

Oregon chemists eye improved thin films with metal substitution: Solution-based inorganic process could drive more efficient electronics and solar devices July 21st, 2014

Steam from the sun: New spongelike structure converts solar energy into steam July 21st, 2014

3-D nanostructure could benefit nanoelectronics, gas storage: Rice U. researchers predict functional advantages of 3-D boron nitride July 15th, 2014

Fuel Cells

Media Advisory: Minister Rempel to Announce Support for Alberta's Nanotechnology Sector June 20th, 2014

Evolution of a Bimetallic Nanocatalyst June 6th, 2014

University of Surrey collaborates with India and Tata Steel to revolutionise renewable energy March 26th, 2014

Novel membrane reveals water molecules will bounce off a liquid surface: Study may lead to more efficient water-desalination systems, fundamental understanding of fluid flow March 16th, 2014


Harris & Harris Group Invests in Unique NYC Biotech Accelerator July 29th, 2014

Seeing is bead-lieving: Rice University scientists create model 'bead-spring' chains with tunable properties July 28th, 2014

FEI adds Phase Plate Technology and Titan Halo TEM to its Structural Biology Product Portfolio: New solutions provide the high-quality imaging and contrast necessary to analyze the 3D structure of molecules and molecular complexes July 28th, 2014

Scientists Test Nanoparticle "Alarm Clock" to Awaken Immune Systems Put to Sleep by Cancer July 25th, 2014

The latest news from around the world, FREE

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

Nanotechnology Now Featured Books


The Hunger Project

© Copyright 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE