In this paper, the synthesis of carbon nanowalls (CNWs) by the chemical vapor deposition method in the plasma of a radio frequency (RF) capacitive discharge is considered. The so-called ``CNWs'' are one of the allotropes of carbon, which are interesting from both the practical and theoretical points of view. Because of their large surface, CNWs are a perfect electrode material for electronic devices. CNWs were synthesized at relatively low values of RF power, and it was found that an increase in the discharge power caused a decrease in the height of CNWs and an increase in their thickness. The study of graphitization of the CNW structure showed that synthesized CNWs had a low number of defects in the structure. The obtained results could be useful for the low-cost production of CNWs by the plasma-enhanced chemical vapor deposition (PECVD) method.

The aim of this work is to study the influence of gas temperature on the nucleation and growth mechanism of nanoparticles in order to deeper understand the growth process of carbonaceous nanoparticles in the plasma of a capacitively coupled radio frequency (RF) discharge. For this purpose, a method based on the time evolution of the self-bias voltage amplitude Vdc was used. The obtained results show that the synthesis (nucleation and growth) time of nanoparticles depends on plasma parameters: RF power and gas temperature. It was found that with an increase in the gas temperature from 25 °C (room temperature) up to 100 °C, the nucleation time increases by four times and with a decrease in the temperature from 25 °C to -20 °C, the nucleation requires half the time. The obtained experimental data and calculations, based on the orbital motion limited theory, give an opportunity to predict the values of nanoparticle diameter and concentration in the plasma-enhanced chemical vapor deposition (PECVD) process in a wide range of gas temperature. These results are important for practical applications of nanoparticle growth control in PECVD processes.

Today, the technologies used to produce monodisperse microparticles are very expensive. Due to the wide application of monodisperse/small-dispersed microparticles in various areas of industries, their high cost, and in order to contribute to the decrease in their prime cost, we have developed a new method of production of the small-dispersed/monodisperse microparticles in the plasma of the combined radio-frequency (RF) and (dc/ac) arc discharges. The advantage of the proposed method is the production of the small-dispersed/monodisperse microparticles in the range of 1-50 μm. The dispersivity and the average size (diameter) of the small-dispersed microparticles are easily controlled by varying the parameters of the RF discharge.