聚砜基阴离子交换膜对双电层电容器性能的影响

Effect of Anion Exchange Membranes Derived from Polysulfone on the Performance of Electrical Double-Layer Capacitors

二氧化硅纳米粒子分别被硅烷偶联剂二甲基十八烷基[3-三甲氧基硅丙基]氯化铵和此硅烷偶联剂与壬基酚聚氧乙烯醚磺酸钠生成的离子液体接枝,然后2种功能化的二氧化硅分别与氯甲基化双酚A型聚砜共混,制备阴离子交换膜,用作双电层电容器的聚合物电解质隔膜。采用傅里叶变换红外光谱、热重分析仪和扫描电镜对功能化二氧化硅粒子的结构与形貌进行表征,证明二氧化硅接枝成功。阴离子交换膜的离子交换容量、吸水率、溶胀率、力学性能及由此组成的双电层电容器性能的测试表明,使用聚砜基阴离子交换膜的双电层电容器在1 A/g的电流密度下,活性炭比电容与多孔聚丙烯膜/KOH溶液体系的双电层电容器相当,约为110 F/g;而且1000次充放电循环后,比电容保持率接近100%。

Silica nanoparticles were firstly grafted with hydrophilic organic chains or room temperature ionic liquid,and then they were doped with chloromethylated polysulfone to prepare composited anion-exchange membranes for the electrical double-layer capacitor(EDLC).The grafting of silica nanoparticles was confirmed by Fourier transform infrared spectroscopy,thermogravimetric analysis,scanning electron microscopy.The properties of anion-exchange membranes including water uptake,swelling ratio,mechanical property,ionic conductivity and performance of EDLCs were investigated.The EDLCs using anion-exchange membranes based on polysulfone show specific capacitances of 110 F/g at a current density of 1 A/g,which is comparable to the value of the EDLC using porous polypropylene membranes and KOH.Moreover,the retention rates of these EDLCs are close to 100%after 1000 cycles at a current density of 1 A/g.