University of Arkansas (Little Rock, AR) chemistry Professor Tito Viswanathan has developed a novel microwave method to produce carbon-metal nanocomposites. The process of synthesizing carbon and carbon-metal composites uses a microwave-assisted method to obtain nanoscale carbon-metal composites from carbon-containing precursors, such as lignins, tannins, lignosulfonates, tanninsulfonates, and their derivatives.
The process is quick and inexpensive in comparison to the known technologies. Moreover, it represents a deviation from conventional heating source as well as raw materials, many of which are non-renewable resource based. It also allows the formation of metal nanoparticles either pristine or on carbon support with high surface area.
The novel methods of synthesizing carbon-metal composites includes using metal ions in the presence of an organic compound, which is one of cellulose; hydroxyalkylcellulose such as hydroxyethylcellulose, methylcellulose, carboxymethylcellulose; cyclodextrins; chitin and chitosan; starch; guar gum and polysaccharides.
Viswanathan’s novel process for synthesizing metal particles in the reducing or non-oxidizing environment generated during the microwave process can be accomplished without the need to use reducing gases, such as H2 gas, or inert gases, such as Ar and N2 gases, during the process. The process allows simultaneously producing carbon from lignin and reducing the metal ions, such as Ni, Cu, to elemental metal such that nanoparticles of carbon and metal are produced after dispersion.
Viswanathan, in a further aspect, found a way of synthesizing Ni2P nanoparticles in the reducing or non-oxidizing environment generated during the microwave process without the need to use reducing gases, such as H2 gas, during the process.
Viswanathan also developed a novel method for synthesizing Cu3P and Cu2S nanoparticles in the reducing or non-oxidizing environment generated during the microwave process without the need to use reducing gases, such as H2 gas, during the process.
Viswanathan also developed a process for the preparation of carbon nanostructures as well as carbon-metal nanostructures by applying microwave radiation to a carbon-containing precursor, such as lignins, tannins, lignosulfonates, tanninsulfonates and their derivatives. The microwave radiation is applied at a frequency of 900 MHz to 5.8 GHz, or more preferably at a frequency of 2.45 GHz for a period of 30 seconds to 60 minutes, or more preferably for a period between 4 minutes and 30 minutes. The process may take place either in the presence of air, in the presence of a non-oxygenated atmosphere or in the absence of air.
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Nanotechnology is widely regarded as one of the most promising future technologies. But little nano research is aimed at preparing this technology for real production. Erwin Kessels, associate professor in the department of Applied Physics of TU/e, will use his Vici grant to close the gap between lab research and the industrial production of, for instance, solar cells and new nano-electronics.