多孔镍/碳纳米管中空纤维膜的制备与结构表征

Preparation and structure characterization of porous nickel/CNTs hollow fiber membrane

泡沫镍作为电极活性材料的常用骨架,其孔径在500μm以上,为了制备出孔径小、空间利用率高的多孔金属集流体材料,探索了多孔镍/碳纳米管(Ni/CNTs)中空纤维膜的制备新工艺.首先配制包含金属镍粉的铸膜液,通过干-湿纺丝工艺得到中空纤维生坯材料,经烧蚀掉有机物后,金属粉末烧结自组装成多孔镍中空纤维膜;然后以镍膜为基体负载催化剂后,采用化学气相沉积法在镍膜上直接生长CNTs制得多孔Ni/CNTs中空纤维复合膜.通过实验可知:铸膜液配比为wNi∶wPAN∶wPVP∶wNMP=50∶8∶1∶41,纺丝参数为采用插入管式喷丝头,其芯液流量为50 m L/min,计量泵泵供量为8 m L/min,釜内氮气压力为0.1 MPa,喷丝孔直径为1.5 mm,插入管外径为2.5 mm;在950℃还原性气氛下,烧结可以得到孔径5μm左右的多孔镍中空纤维膜.采用0.001 mol/L的Ni/Y催化剂,550℃下混合气体比例vAr∶vH2∶vC2H2=200∶50∶8时进行化学气相沉积,可在中空纤维Ni膜表面可生长出直径20~30 nm的CNTs.

As a common electrode active material skeleton,the diameter of the nickel foam is beyond 500μm.In order to prepare a porous metal current collector material with small pore diameter and high space utilization efficiency,a novel approach to prepare porous nickel/carbon nanotubes(Ni/CNTs)hollow fiber membranes was proposed.Firstly,the hollow fiber Ni membranes were fabricated by singtering the raw hollow fibers,which were prepared by dry-wet spinning process using the organic cast solution containing Ni powders.CNTs were directly grown on the Ni surface by CVD to obtain the composite membranes.By optimizing,the cast solution composition was wNi∶wPAN∶wPVP∶wNMP=50∶8∶1∶41,spinning parameters for the flow meter was 50 mL/min,its metering pump was 8 mL/min,the tank pressure by N2 was 0.1 MPa,the diameter of spinneret is 1.5 mm and the tube is 2.5 mm in diameter,and then porous nickel hollow fiber membrane with pore size of about 5μm can be obtained by sintering at a reductive atmosphere at 950℃.The chemical vapor deposition was carried out using Ni/Y with 0.001 mol/L catalyst at 550℃mixed gas ratio vAr∶vH2∶vC2H2=200∶50∶8,CNTs having a diameter of 20-30 nm can be grown on the surface of the hollow fiber Ni membranes.