Abstract
The present paper describes the efficiency of the synthesis of multi-walled carbon nanotubes (MWCNTs), which is achieved through the implementation of a non-standard approach to the preparation of a Ni/MgO catalyst. The catalyst required for MWCNTs synthesis was obtained through chemical vapor deposition method. At the same time, the pre-catalyst was treated by electromagnetic field, ultrasound and microwave waves methods. It was proved that the treatment of the catalyst initial components solution with the electromagnetic field, ultrasound and microwaves contributes to an increase in the yield of the synthesized MWCNTs by 50, 30 and 70%. Besides, ultrasonic treatment may be used if MWCNTs of relatively low degree of a defect are required. The proposed approach is economically feasible since small additional energy costs lead to a more complete conversion of carbon-containing raw materials into the target product at the activation stage. The reported method may be used to prepare MWCNTs of different types economically; leading to its industrial application to produce different types of MWCNTs.