生物质褶皱微球的制备及其在超级电容器中的应用

Preparation of biomass wrinkled microspheres and its application in supercapacitors

本文利用纤维素纳米晶体(CNC)和淀粉(Starch)间氢键作用,CNC和壳聚糖(Chitosan)自组装作用,通过喷雾干燥制备生物质褶皱微球并探究其在超级电容器中的应用.结果表明:当CNC和Starch、Chitosan质量浓度比分别为10∶7和5∶5时可以制备出中空半球形褶皱颗粒和规则球形褶皱颗粒,其颗粒直径分别在5μm和3.5μm左右.在经过800℃碳化2 h后仍能保持原有形貌结构,没有发生结构的塌陷和破环.EDS分析表明,CNC-Starch碳化后只含有C、O元素,而CNC-Chitosan含有C、N、O元素,杂原子(N)掺杂可以提高活性物质的浸润性和导电性.在0.5 A/g电流密度下CNC-Starch和CNC-Chitosan分别具有89 F/g和126 F/g的比电容.得益于CNC-Chitosan规则的球形褶皱结构和自身N元素自掺杂,CNC-Chitosan具有更好的电化学性能.

In this paper,hydrogen bonding between cellulose nanocrystals(CNC)and starch,and self-assembly of CNC and chitosan were used to prepare wrinkled biomass microspheres by spray drying and to explore their application in supercapacitors.The results show that when the mass concentration ratios of CNC and Starch and Chitosan are 10∶7 and 5∶5,forming hollow hemispherical wrinkled particles and regular spherical wrinkled particles,respectively.The particle diameters are about 5μm and 3.5μm,respectively.After carbonization at 800℃for 2 h,the original morphology and structure could still be maintained,and no structural collapse and ring break occurred.EDS analysis showed that CNC-Starch contained only C and O elements after carbonization,while CNC-Chitosan contained C,N,O elements.CNC-Starch and CNC-Chitosan have specific capacitors of 89 F/g and 126 F/g respectively at a current density of 0.5 A/g.Thanks to the regular spherical folding structure of CNC-Chitosan and its own self-doping N element,CNC-Chitosan has better electrochemical performance.