Surface modification and properties modulation of rGO film by short duration H2 and NH3 plasma treatment

Abstract

Reduced graphene oxide (rGO) is a versatile material due to the presence of oxygen functionalization. One of the methods to tune the properties of rGO for the specific application is plasma treatment. Plasma H 2 and NH 3 are known introduced surface defects for increasing surface reactivity and inducing substitutional doping on rGO film. They need to be further discussed with the changes in electrical and optical properties of the film for the construction of devices such as electrical, optical, and electro-optical sensors. This article reports the effect of H 2 and NH 3 plasma treatment on the surface and properties of rGO film using a variety in plasma power and temperature. We found low-power H 2 plasma at low- and medium-temperature induced further de-oxygenation of rGO. A tiny etching effect by H 2 plasma slightly reduces the conductivity, σ to 54.01 S/cm from the reference rGO value of 448.90 S/cm. Low-power H 2 plasma at high-temperature left the high defective sites due to plasma etching. The σ was reduced to 8.04 S/cm. Medium-temperature medium-power NH 3 plasma did not effective for N-doping. An etching effect by NH 3 plasma noticeably reduces the σ to 5.79 S/cm. Medium-temperature high-power and high-temperature medium-power NH 3 plasma induce N-doping but at the same time significantly etch the rGO. They significantly reduce the hole concentration and lower the σ to 0.48 S/cm. High-power high-temperature NH 3 plasma rigorously induces N-doping but extreme plasma etching results in poor surface condition and film discontinuity. The film exhibited electron as a majority carrier but with the lowest σ of 0.05 S/cm.