Recently, the renewable energy such as solar power, wind power, hydrogen, and fuel cell is emerging due to depletion of fossil fuel. Accordingly we need for an efficient energy storage device that can be used when energy is needed. Currently, the energy devices such as lithium ion battery, fuel cell...
Recently, the renewable energy such as solar power, wind power, hydrogen, and fuel cell is emerging due to depletion of fossil fuel. Accordingly we need for an efficient energy storage device that can be used when energy is needed. Currently, the energy devices such as lithium ion battery, fuel cell, solar cell, lead acid battery, and supercapacitor are used as representative energy devices. Among them, the supercapacitor has high powder density, fast charge/discharge, long life, and non-toxicity. The supercapacitor consists of two electrodes, an electrolyte, and a separator. The porous carbon, graphene, and CNT are used as electrode material because of their high specific surface area and electrical conductivity. However, the low energy density of the supercapacitor has been a serious obstacle in various applications. Such problems can be solved by incorporating heteroatoms into graphitic structure, resulting in enhancement of electrochemical performance.
When sulfur atoms are introduced into graphene, sulfur atoms are more electronegative than carbon electrons and exhibit n-type conductivity, thus improving electrical conductivity. In addition, since the sulfur functional groups are formed and electrochemically activated, the redox reaction is promoted and the specific capacitance can be improved.
In this study, sulfur-doped graphene and de-doped graphene were synthesized by thermal-chemical vapor deposition (T-CVD) using a thiophene source and subsequent heat-treatment in H2 atmosphere.
XPS and Raman spectra confirmed the removal of the sulfur. SEM and BET analysis showed no significant change in surface morphology and structure. Electrochemical analysis was performed on the organic electrolyte to evaluate the sulfur doping effect on the graphene structure as an electrode of the supercapacitor. Sulfur-doped graphene electrodes showed 2.6 times higher specific capacitance at the same current density and their rate capability dramatically increased at high current density compared to the un-doped ones. Also, sulfur-doped graphene electrode represented stable at high scan rates and its resistance also decreased.
Recently, the renewable energy such as solar power, wind power, hydrogen, and fuel cell is emerging due to depletion of fossil fuel. Accordingly we need for an efficient energy storage device that can be used when energy is needed. Currently, the energy devices such as lithium ion battery, fuel cell, solar cell, lead acid battery, and supercapacitor are used as representative energy devices. Among them, the supercapacitor has high powder density, fast charge/discharge, long life, and non-toxicity. The supercapacitor consists of two electrodes, an electrolyte, and a separator. The porous carbon, graphene, and CNT are used as electrode material because of their high specific surface area and electrical conductivity. However, the low energy density of the supercapacitor has been a serious obstacle in various applications. Such problems can be solved by incorporating heteroatoms into graphitic structure, resulting in enhancement of electrochemical performance.
When sulfur atoms are introduced into graphene, sulfur atoms are more electronegative than carbon electrons and exhibit n-type conductivity, thus improving electrical conductivity. In addition, since the sulfur functional groups are formed and electrochemically activated, the redox reaction is promoted and the specific capacitance can be improved.
In this study, sulfur-doped graphene and de-doped graphene were synthesized by thermal-chemical vapor deposition (T-CVD) using a thiophene source and subsequent heat-treatment in H2 atmosphere.
XPS and Raman spectra confirmed the removal of the sulfur. SEM and BET analysis showed no significant change in surface morphology and structure. Electrochemical analysis was performed on the organic electrolyte to evaluate the sulfur doping effect on the graphene structure as an electrode of the supercapacitor. Sulfur-doped graphene electrodes showed 2.6 times higher specific capacitance at the same current density and their rate capability dramatically increased at high current density compared to the un-doped ones. Also, sulfur-doped graphene electrode represented stable at high scan rates and its resistance also decreased.
주제어
#Sulfur-Doped Supercapacitor CVD graphene
※ AI-Helper는 부적절한 답변을 할 수 있습니다.