Study On The Performance Of Sulfur Doped Graphene Aerogel Supercapacitor Electrode

As a new electrode material,graphene has the phenomenon of agglomeration due to its instability,which blocks its further development in electrode materials.In order to reduce agglomeration and increase specific capacity of electrode materials,methods of introducing sulfur atoms into the graphene structure have been used in many experiments.However,the maximum amount of sulfur doped into graphene,and the influencing factors of the electrochemical properties of sulfur-doped graphene need to be studied systematically.In this paper,Na2S2O3 was selected as the sulfur source,and then the effect of the preparation conditions on the electrochemical properties was studied.The results showed the preparation conditions of sulfur-doped graphene electrode materials with the best electrochemical properties by one-step hydrothermal method,such as experimental time、temperature and doping amount.For graphene oxide,when the hydrothermal temperature and time were 155℃ and 12 h,the electrochemical performance of the graphene was the best,and the specific capacitance was up to 139 F/g(1 A/g).For the sulfur doped graphene aerogels,when the hydrothermal temperature and time were 160℃ and 12 h,the mass ratio of carbon and sulfur was 1:2,and the compression pressure was 4 MPa,the electrochemical performance of the sulfur doped graphene was the best,and the specific capacitance was up to 304 F/g(1 A/g),which was obviously higher than that of the undoped graphene material.Finally,a simulated symmetrical supercapacitor was fabricated by using the S-doped graphene as electrode under the optimum doping condition.The electrochemical performance showed the specific capacitance was 212 F/g(1 A/g)and the power density was 480 W/kg.In addition,it had smaller contact resistance,good rate performance and great cycle stability.