1 Efficient reduction of graphene oxide using Tin-powder and its electrochemical performances for energy storage electrode material Nam Hoon Kim, a Partha Khanra, a Tapas Kuila, b Joong Hee Leea, c,d* a WCU Program, Department of BIN Fusion Technology, Chonbuk National University, Jeonju, Jeonbuk, 561-756, Republic of Korea b Surface Engineering & Tribology Division, CSIR-Central Mechanical Engineering Research Institute, Council of Scientific & Industrial Research (CSIR), Mahatma Gandhi Avenue, Durgapur -713209, India c BIN Fusion Research Center, Department of Polymer & Nano Engineering, Chonbuk National University, Jeonju, Jeonbuk, 561-756, Republic of Korea d Department of Hydrogen and Fuel Cell Engineering, Chonbuk National University, Jeonju, Jeonbuk, 561-756, Republic of Korea. * Correspondence to: Prof. Joong Hee Lee( jhl@jbnu.ac.kr) Table S1 Comparison of properties of reduced GOs produced by various reducing agents Reducing agent Temperature ( o C) Reduction Time C:O ratio by XPS (atomic ratio) Electrical conductivity (S m -1 ) Specific capacitance (F g -1 ) Reference No Al(powder)/ HCl RT 30 min 18.6 2,100 ------- 1 Al(foil)/HCl RT 6 h 21.11 12,530 ------- 2 Al(foil)/NaOH RT 30 min 5.35 1,120 ------- 2 Fe(powder)/ HCl RT 6 h 7.9 2,300 ------- 3 Zn(powder)/ ammonia RT 10 min 8.05 2,160 116 at 0.05 A g -1 4 Zn(filings)/H 2 SO 4 RT 2 h 21.2 3,416 176 5 Zn(powder)/NaOH RT 20 min 17.96 7,540 ------- 2 Zn(powder)/ neutral solutions in the presence of EDTA* RT 1 min Ultrasonic ation 33 14,200 ------- 6 Zn(powder)/NaOH RT 1 min Ultrasonic ation 31.2 13,500 ------- 6 Zn(powder)/NaOH RT 6 h 6.02 ------- 7 Zn(powder)/NaOH 100 6 h 7.39 ------- 7 Zn(powder)/HCl RT 30 min 8.2 650 ------- 8 Ni(powder)/HCl RT 24 h ------- 9 Mg(ribbons )/HCl RT 5 min 10.12 ------- 10 NaBH 4 RT 2 h 8.6 45 ------- 11 Hydrazine hydrate 100 24 h 10.3 ~200 ------- 12 Electronic Supplementary Material (ESI) for Journal of Materials Chemistry A This journal is © The Royal Society of Chemistry 2013