Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Explosive Nanotechnology

14.08.2013
Highly reactive nanoenergetic formulations based on periodate salts

Whether they are rocket propellants or fireworks, all explosives contain a fuel and an oxidizing agent. Sometimes both are in the same molecule, like in TNT; sometimes the explosive is a mixture, like Thermite.



In mixtures, the smaller the particles, the higher the explosive force. American scientists have reported in the journal Angewandte Chemie a new aerosol spray drying method for the generation of periodate nanoparticles that can be used in the formulation of highly reactive explosives.

Energetic mixtures usually have a higher energy density than explosive materials with both components in a single molecule. However, mixtures generally release the energy more slowly because the reaction partners have to find each other.

Nanoenergetics researchers are attempting to achieve faster and more intensive mixing of the fuel and oxidizing agents by drastically reducing the scale of the distances involved. In most nanoenergetic formulations, nanoaluminum (aluminum nanoparticles) is used as the fuel and metal oxides as the oxidizing agents.

Highly oxidizing compounds with high oxygen content, such as perchlorate are an alternative, but cannot be stored as long, partly because they are very hygroscopic. Perchlorates can also cause health problems and environmental damage. Periodates are possible substitutes. They are minimally toxic and don’t absorb water. However, the production of nanoparticles of periodate salts has proven very difficult.

A team led by Michael R. Zachariah at the University of Maryland has now overcome this problem. Their secret is a simple but versatile aerosol spray drying process. An aqueous solution is continuously atomized to form microdroplets, which give off water as they dry, forming nanoscopic grains of salt.

In formulations with nanoaluminum as fuel, this new nanoperiodate demonstrated superior reactivity. “Our formulations resulted in the highest gas pressure pulses described to date for nanoenergetic materials,” reports Zachariah.

By using special electron microscopic and mass spectrometric techniques in which the samples can be heated extremely fast, the researchers explored the reaction mechanisms involved.

They discovered that the release of gas-phase oxygen is critical for the ignition and combustion of the periodate formulations. The decomposition of potassium periodate (KIO4) takes place in two steps. First oxygen splits off.

The resulting KIO3 then further decomposes to potassium iodide (KI) and oxygen. “Different from most metal oxide decompositions, the first step of periodate decomposition is exothermic, releasing heat,” explains Zachariah. “This is presumably the reason for the low ignition temperature.”

About the Author
Dr. Michael R. Zachariah is a Professor of Chemical Engineering and Chemistry at the University of Maryland. His expertise is in the area of nanoparticle synthesis and metrology, and the high temperature materials chemistry of nanomaterials including those related to energetic.
Author: Michael Zachariah, University of Maryland, College Park (USA), http://www.chem.umd.edu/michael-zachariah/
Title: Super-reactive Nanoenergetic Gas Generators Based on Periodate Salts
Angewandte Chemie International Edition, Permalink to the article: http://dx.doi.org/10.1002/anie.201303545

Michael Zachariah | Angewandte Chemie
Further information:
http://pressroom.angewandte.org

More articles from Life Sciences:

nachricht Symbiotic bacteria: from hitchhiker to beetle bodyguard
28.04.2017 | Johannes Gutenberg-Universität Mainz

nachricht Nose2Brain – Better Therapy for Multiple Sclerosis
28.04.2017 | Fraunhofer-Institut für Grenzflächen- und Bioverfahrenstechnik IGB

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Fighting drug resistant tuberculosis – InfectoGnostics meets MYCO-NET² partners in Peru

28.04.2017 | Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

 
Latest News

Wireless power can drive tiny electronic devices in the GI tract

28.04.2017 | Medical Engineering

Ice cave in Transylvania yields window into region's past

28.04.2017 | Earth Sciences

Nose2Brain – Better Therapy for Multiple Sclerosis

28.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>