Hydrophilic Surface Treatment of Carbon Powder Using CO2 Plasma Activated Gas

Seungryul Yoo,Kiyong Lee,Dongchan Seok,Yongho Jung

doi:10.3390/coatings11080925

Abstract

Carbon powders exhibit electrical conductivity that causes the powders to agglomerate due to the applied electrostatic forces and discharges capacitance when used for surface treatments with plasma sources. To avoid this obstacle, a non-direct method is used with active gas that is generated through plasma. This active gas is in contact with the carbon powder so that the hydrophilic characteristics are formed. It is the carboxyl COO− functional group that causes hydrophilic improvement and it is shown to increase in the carbon surface after soft oxidation. The wettability of carbon powder gradually improves with more plasma treatment time. This is shown through a simple water dispersion test. Eventually, the dispersed aqueous solution gradually separates the powder, which either floats or sinks. The sample treated for 60 min is shown to continuously sustain dispersibility in water over a long period of time.

Highlights

IntroductionCarbon powders are useful in many ways, such as colorings, light-blocking additives, and conductive materials that are used in secondary batteries and capacitors
Water was added to 0.05 g of the carbon powder sample
The experiments were conducted with a batch-type reactor that mixes the carbon powder with the CO2 discharge gas, which is generated by a plasma device employing dielectric-barrier discharge (DBD) electrodes at atmospheric pressure

Summary

Introduction

Carbon powders are useful in many ways, such as colorings, light-blocking additives, and conductive materials that are used in secondary batteries and capacitors. These carbon powders are added to the production of slurry that is used as an electrode material, in which some type of suitable dispersion is required [1,2,3]. On the other hand, using more additives could reduce the carbon content and degrade the electrical properties [4,5] Due to this difficulty, there have been various surface treatments [6]

Methods

Results

Discussion

Conclusion