掺银木质素基碳纤维的制备及电催化性能研究

Preparation and Electrocatalytic Properties of Silver Doped Lignin Based Carbon Fibers

用静电纺丝法制备了高浓度木质素基纤维垫,经热稳定和碳化,纤维垫转化为木质素基碳纤维,用作银纳米颗粒载体。用环境扫描电子显微镜(SEM)、傅里叶变换红外光谱(FT-IR)、激光拉曼光谱(Raman)、能量色散X-射线光谱(EDS)等对材料进行表征,组装成全固态锌空气电池进行测试。当木质素、聚乙烯醇(PVA)和银纳米颗粒质量比为4∶4∶1时,制备的掺银纳米颗粒木质素基碳纳米纤维(CNFs-Ag)催化剂的极限电流密度为5 mA/cm^(2),塔菲尔斜率为112.6 mV/dec,电子转移数为3.9,毒性物质产率低于10%,稳定性及耐甲醇性能优于20%(wt)商用铂碳催化剂(Pt/C),具有优异的氧还原电催化性能和广阔的的应用前景。

High concentration lignin-based fiber mats were prepared by electrospinning using all green and renewable raw materials.After thermal stabilization and carbonization,the fiber mats were converted into lignin-based carbon fibers,which were used as carriers for loading silver nanoparticles.Environmental scanning electron microscopy(SEM),Fourier transform infrared spectroscopy(FT-IR),laser Raman spectroscopy(Raman),energy dispersive X-ray spectroscopy(EDS)and other techniques were used to characterize the materials,and an all solid-state zinc air battery was assembled for testing.When the mass ratio of lignin,polyvinyl alcohol(PVA),and silver nanoparticles is 4∶4∶1,the limit current density of the silver doped nanoparticle lignin based carbon nanofibers(CNFs-Ag)catalyst prepared can reach 5 mA/cm^(2),the Tafel slope is as low as 112.6 mV/dec,the electron transfer number is about 3.9,the yield of toxic substances is less than 10%,and its stability and methanol resistance performance are superior to commercial 20%(wt)platinum carbon catalysts(Pt/C),It has excellent electrocatalytic performance for oxygen reduction and broad application prospects,showing great potential in the development of high-performance cathode materials.