New Physics: Sae Mulli, Vol. 67, No. 3, March 2017, pp. 333∼337 http://dx.doi.org/10.3938/NPSM.67.333 Economical Thermal Reduction of Graphite Oxide for Supercapacitor Applications Minh-Hai Tran · Hae Kyung Jeong * Department of Physics, Institute of Basic Science, Daegu University, Gyeongsan 38453, Korea (Received 20 November 2016 : revised 23 December 2016 : accepted 25 December 2016) Graphite oxide (GO) is thermally reduced in three diferent conditions (800 ◦ C and 400 ◦ C with ramping rates of 10 ◦ C·min −1 and 400 ◦ C with a ramping rate of 50 ◦ C·min −1 ). In this study, Go produce during the three conditions were characterized for supercapacitor applications. The thermal reduction of Go at high temperature is known to be very efcient. However, the results of our research demonstrates that the thermal reduction at low temperature with a fast ramping rate (50 ◦ C·min −1 ) is more efective. Electrochemical results for the reduced GO at low temperature with a higher ramping rate are superior to these for reduced GO at high temperature, proving that the fast ramping rate at low temperature is likely to provide economical and efective thermal reduction of GO. PACS numbers: 81.05.ue, 81.20.Ka, 82.47.Uv Keywords: Graphite oxide, Reduction, Supercapacitor I. INTRODUCTION Graphite oxide (GO) has received tremendous atten- tion in recent years because of its unique properties, such as hydrophilic property [1], existence of functional groups [2], an alternative of graphene [3], and a fatform of vari- ous composites [4] for various applications. GO has been also reduced in many methods (chemical, physical, elec- trochemical et al.) to improve conductivity and modify morphologies for proper applications [5–7]. One of typical reduction methods is thermal treat- ments. It has been known that it is more environmen- tal friendly than that of a chemical method due to the chemical-free requirement and more efcient reduction than the chemical reduction [8]. The high efcient re- duction by the thermal treatment, however, needs very high temperature, even more than 800 - 1000 ◦ C[9– 11]. The high temperature has negative efect because it needs high energy to increase the high temperature for longer time. Developing an alternative method in which the high temperature is not required to obtain the efec- tive reduction of GO is necessary. ∗ E-mail: outron@gmail.com In this paper three diferent thermal conditions (800 ◦ C and 400 ◦ C with the ramping rate of 10 ◦ C·min −1 and 400 ◦ C with the ramping rate of 50 ◦ C·min −1 ) are inves- tigated for the efective thermal reduction of GO, and three samples are characterized for supercapacitor appli- cations. As a result, the reduction at the low tempera- ture with the higher ramping rate could provide efective reduction efect on GO compared to the reduction at the high temperature with the low ramping rate. The fast ramping rate, even at the low temperature, could max- imize a thermal shocking efect on GO layers, leading the efective thermal reduction of GO. The electrochem- ical properties of the samples are also corresponding to the reduction level, and the electrochemical impedance of the reduced GO at the low temperature with the fast ramping rate is the lowest. II. EXPERIMENTAL GO is synthesized by the modifed Brodie method as following. Natural graphite (100 mesh, Sigma Aldrich) of 1 g was ground with sodium chlorate (99%, Sigma This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.