CAJ | 학술논문

以氧化石墨凝胶制备的氧化石墨烯溶胶为前驱体,在120-220°C条件下,采用水热法制备了系列不同还原程度的三维还原氧化石墨烯,采用扫描电镜(SEM), X射线衍射(XRD),傅里叶变换红外(FTIR)光谱, X射线光电子能谱(XPS)和电化学测试等手段研究了水热反应温度对材料形貌、结构和超级电容性能的影响.结果表明：采用水热法制备的三维还原氧化石墨烯呈多孔网状结构,材料的体积和内部网状孔径随着水热反应温度的升高而减小；同时,氧化石墨烯的还原程度随反应温度的升高而增加,有序度提高,其结构逐渐向着类石墨结构转化；而材料的比电容和能量密度则随反应温度的升高呈现出先增大后减小的趋势,且均以双电层电容为主；相比之下,当水热反应温度为180°C时,制备的三维还原氧化石墨烯具有最佳的超级电容性能,在电解液为6 mol?L-1的KOH溶液中,0.5 A?g-1电流密度下其比电容达到315 F?g-1,10 A?g-1时仍能保持212 F?g-1的高比容量,能量密度为40.5 Wh?kg-1,5000次循环后比电容保持率为86%,表现出了良好的电化学性能.
이양화석묵응효제비적양화석묵희용효위전구체,재120-220°C조건하,채용수열법제비료계렬불동환원정도적삼유환원양화석묵희,채용소묘전경(SEM), X사선연사(XRD),부리협변환홍외(FTIR)광보, X사선광전자능보(XPS)화전화학측시등수단연구료수열반응온도대재료형모、결구화초급전용성능적영향.결과표명：채용수열법제비적삼유환원양화석묵희정다공망상결구,재료적체적화내부망상공경수착수열반응온도적승고이감소；동시,양화석묵희적환원정도수반응온도적승고이증가,유서도제고,기결구축점향착류석묵결구전화；이재료적비전용화능량밀도칙수반응온도적승고정현출선증대후감소적추세,차균이쌍전층전용위주；상비지하,당수열반응온도위180°C시,제비적삼유환원양화석묵희구유최가적초급전용성능,재전해액위6 mol?L-1적KOH용액중,0.5 A?g-1전류밀도하기비전용체도315 F?g-1,10 A?g-1시잉능보지212 F?g-1적고비용량,능량밀도위40.5 Wh?kg-1,5000차순배후비전용보지솔위86%,표현출료량호적전화학성능.
Three-dimensional reduction of graphene oxide with a series of different degrees of reduction was performed by the hydrothermal method in the temperature range from 120 to 220 °C, with graphene oxide sols as the precursor and prepared by graphite oxide gels. The effect of the temperature of the hydrothermal reaction on the materials1 appearance, structure, and super capacitor performance was investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and electrochemical measurements. The results show that the prepared three dimensional reduction of graphene oxide was porous and reticulated, and its volume and inner mesh aperture gradual y decreased with increasing temperature, while its degree of reduction and order increased at the same time, and its structure gradual y transformed to the graphite oxide structure. However, the materials′specific capacitance and energy density showed the tendency of first increasing and then decreasing, with the electric double-layer capacitor mainly remaining. The three-dimensional reduction of graphene oxide materials at 180 °C resulted in the best super capacitor performance, with a specific capacitance of 315 F?g?1 when the current density was 0.5 A?g?1 and 212 F?g?1 when the current density was 10 A?g?1. Its energy density was 40.5 Wh?kg?1 and its specific capacitance was 86%after 5000 cycles, with al these properties indicating its good super capacitor performance.