以磺化石墨烯(sGNS)为基板材料,通过界面聚合方法制备出不同分级结构磺化石墨烯负载聚苯胺(sGNS/PANI)复合材料,并系统研究了氧化剂类型对复合材料的化学组成、形貌结构和超级电容特性的影响.结果显示,过硫酸铵为氧化剂合成的复合材料中...以磺化石墨烯(sGNS)为基板材料,通过界面聚合方法制备出不同分级结构磺化石墨烯负载聚苯胺(sGNS/PANI)复合材料,并系统研究了氧化剂类型对复合材料的化学组成、形貌结构和超级电容特性的影响.结果显示,过硫酸铵为氧化剂合成的复合材料中PANI的产率和氧化程度最高,其形貌呈现出sGNS垂直生长PANI纳米短棒阵列结构,PANI的共轭程度和结晶性均较高,从而赋予复合材料高的比电容(497.3 Fg-1),以及良好的倍率特性和循环稳定性(2000次循环后比电容仅损失5.7%).当以三氯化铁为氧化剂时,复合材料中PANI的得率很低,并在sGNS表面形成较薄的包覆层,此时复合材料的比电容最低(228.5 Fg-1),但充放电循环性能较好(2000次循环后比电容的保持率为87.4%).当氧化剂为高锰酸钾时,复合材料中PANI以团聚态颗粒无规堆积在sGNS表面,PANI以无定型结构存在,其比电容虽然较高(419.6 F g-1),但其倍率特性和充放电循环性能较差(2000次循环后比电容损失19.9%).展开更多
An environmentally friendly approach is presented to synthesize sulfonated reduced graphene oxide (S-rGO) by using L-ascorbic acid (L-AA) and aryl diazonium salt of sulfanilic acid. The preparation conditions have...An environmentally friendly approach is presented to synthesize sulfonated reduced graphene oxide (S-rGO) by using L-ascorbic acid (L-AA) and aryl diazonium salt of sulfanilic acid. The preparation conditions have been optimized in order to obtain isolated and conductive S-rGO, and the products have been characterized by Ultraviolet-Visible spectroscopy, Fourier transformed infrared spectroscopy, Raman, X-ray photoelectron spectroscopy and X-ray powder diffraction and electrochemical methods. The results show that the S-rGO sheets possess excellent water-solubility and high electrical conductivity, which implies that the oxygen-containing functional groups have been removed and conjugated sp2 network has been restored. What's more, the electrochemical measurements reveal that the capacitive performance of the S-rGO has been improved compared with the graphene oxide (GO) and the reduced graphene oxide (rGO, reduced by L-AA). The optimum S-rGO exhibits a specific capacitance of 205 F·g^-1 and good cycling stability (3.9% decreasing after 10000 cycles), which are better than those for graphene oxide (109 F·g^-1 and decreasing 6.6% after 10000 cycles) and rGO (139 F·g^-1 and decreasing ll.3% after 10000 cycling). This approach proves a new route to improve the capacitive properties of rGO.展开更多
文摘以磺化石墨烯(sGNS)为基板材料,通过界面聚合方法制备出不同分级结构磺化石墨烯负载聚苯胺(sGNS/PANI)复合材料,并系统研究了氧化剂类型对复合材料的化学组成、形貌结构和超级电容特性的影响.结果显示,过硫酸铵为氧化剂合成的复合材料中PANI的产率和氧化程度最高,其形貌呈现出sGNS垂直生长PANI纳米短棒阵列结构,PANI的共轭程度和结晶性均较高,从而赋予复合材料高的比电容(497.3 Fg-1),以及良好的倍率特性和循环稳定性(2000次循环后比电容仅损失5.7%).当以三氯化铁为氧化剂时,复合材料中PANI的得率很低,并在sGNS表面形成较薄的包覆层,此时复合材料的比电容最低(228.5 Fg-1),但充放电循环性能较好(2000次循环后比电容的保持率为87.4%).当氧化剂为高锰酸钾时,复合材料中PANI以团聚态颗粒无规堆积在sGNS表面,PANI以无定型结构存在,其比电容虽然较高(419.6 F g-1),但其倍率特性和充放电循环性能较差(2000次循环后比电容损失19.9%).
基金Acknowledgement The authors thank the National Natural Science Foundation of China (21574076, 21274082, 21501113, 61504076 and 21407100) and Science Foundation of Shanxi Province (2014011016-1), the Program for New Century Excellent Talents in University (NCET-10- 0926) of China and the Program for the Top Young and Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi (02035290 1014).
文摘An environmentally friendly approach is presented to synthesize sulfonated reduced graphene oxide (S-rGO) by using L-ascorbic acid (L-AA) and aryl diazonium salt of sulfanilic acid. The preparation conditions have been optimized in order to obtain isolated and conductive S-rGO, and the products have been characterized by Ultraviolet-Visible spectroscopy, Fourier transformed infrared spectroscopy, Raman, X-ray photoelectron spectroscopy and X-ray powder diffraction and electrochemical methods. The results show that the S-rGO sheets possess excellent water-solubility and high electrical conductivity, which implies that the oxygen-containing functional groups have been removed and conjugated sp2 network has been restored. What's more, the electrochemical measurements reveal that the capacitive performance of the S-rGO has been improved compared with the graphene oxide (GO) and the reduced graphene oxide (rGO, reduced by L-AA). The optimum S-rGO exhibits a specific capacitance of 205 F·g^-1 and good cycling stability (3.9% decreasing after 10000 cycles), which are better than those for graphene oxide (109 F·g^-1 and decreasing 6.6% after 10000 cycles) and rGO (139 F·g^-1 and decreasing ll.3% after 10000 cycling). This approach proves a new route to improve the capacitive properties of rGO.