Mrs


  Anastasia Novikova  
Ben-Gurion University of the Negev

Green-extraction of carbon thin films from natural mineral Shungite

Anastasia Novikova, Alina Karabchevsky

School of Electrical and Computer Engineering, Ben-Gurion University of the Negev

 

Conventional methods to obtaining carbon layers are based on chemical methods. These techniques are expensive and are not ecology friendly. This is due to the fact that a large volume of raw materials requires a large amount of acids and alkalis, which in turn after processing require special disposal. Therefore, it is necessary to develop or refine existing technologies for the production of carbon films and create new ecology safe and effective methods.

Here we report on the extraction method of thin carbon films out of natural mineral Shungite originated from the Zazhoginsky deposit Russia (Karelia). Shungite contains more than 98 percent of amorphous carbon and refers to hybrid structures consisting of sp1+sp2+ sp3 forms of hybridized carbon atoms. For this reason, it is a rich natural source of carbon.

In our work, we utilized the physical destruction of the mineral by grinding and the process of dispersion. The surface of the mineral has heterogeneous stepped shell spalls typical of shungite. The mineral also contains inclusions of different types and shapes: individual grains larger than 10 nm and spongy inclusions of micro and nanometer size. Studies by Raman spectrometry and X-ray phases analysis have shown that shungite refers to graphite-like mineral structures. Spectral data show that the main constituent of shungite is amorphous carbon insp2 and sp3 forms.TEM images of the processed material revealed that the obtained carbon films withwell-developed surfaces are as small as 200 nanometers. Carbon thin films can be utilized in variety of fields from electronics (electrodes), optics to biotechnology (to create optical chips and biosensors), ecology (sorbents for wastewater, air purification).