Beijing Engineering Research Center of Process Pollution Control, Division of Environmental Technology and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100049, China; State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; University of Chinese Academy of Sciences, Beijing 100049, China.
Environmental Research Academy, North China Electric Power University, Beijing 102206, China.
Carbohydr Polym. 2017 Nov 1;175:223-230. doi: 10.1016/j.carbpol.2017.07.089. Epub 2017 Aug 1.
In order to promote sustainable development, green and renewable clean energy technologies continue to be developed to meet the growing demand for energy, such as supercapacitor, fuel cells and lithium-ion battery. It is urgent to develop appropriate nanomaterials for these energy technologies to reduce the volume of the device, improve the efficiency of energy conversion and enlarge the energy storage capacity. Here, chitosan/cellulose carbon cryogel (CCS/CCL) were designed and synthesized. Through the introduction of zeolite imidazole frameworks (ZIFs) into the chitosan/cellulose cryogels, the obtained materials showed a microstructure of ZIF-7 (a kind of ZIFs) coated chitosan/cellulose fibers (CS/CL). After carbonizing, the as-prepared carbonized ZIF-7@cellulose cryogel (NC@CCL, NC is carbonized ZIF-7) and carbonized ZIF-7@chitosan cryogel (NC@CCS) exhibited suitable microspore contents of 34.37% and 30%, respectively, and they both showed an internal resistance lower than 2Ω. Thereby, NC@CCL and NC@CCS exhibited a high specific capacitance of 150.4Fg and 173.1Fg, respectively, which were much higher than those of the original materials. This approach offers a facile method for improving the strength and electronic conductivity of carbon cryogel derived from nature polymers, and also efficiently inhibits the agglomeration of cryogel during carbonization in high temperature, which opens a novel avenue for the development of carbon cryogel materials for application in energy conversion systems.
为了促进可持续发展，绿色可再生清洁能源技术不断发展，以满足日益增长的能源需求，例如超级电容器、燃料电池和锂离子电池。为这些能源技术开发合适的纳米材料以减小器件的体积、提高能量转换效率和增大储能容量已迫在眉睫。在这里，设计并合成了壳聚糖/纤维素碳水凝胶（CCS/CCL）。通过将沸石咪唑酯骨架（ZIFs）引入壳聚糖/纤维素水凝胶中，得到的材料显示出 ZIF-7（一种 ZIFs）涂覆壳聚糖/纤维素纤维（CS/CL）的微观结构。碳化后，所制备的碳化 ZIF-7@纤维素水凝胶（NC@CCL，NC 是碳化 ZIF-7）和碳化 ZIF-7@壳聚糖水凝胶（NC@CCS）分别显示出合适的微球含量 34.37%和 30%，且它们的内阻均低于 2Ω。因此，NC@CCL 和 NC@CCS 分别表现出 150.4Fg 和 173.1Fg 的高比电容，远高于原始材料的比电容。该方法为提高源自天然聚合物的碳水凝胶的强度和电子电导率提供了一种简便的方法，并且还可以有效地抑制在高温碳化过程中碳水凝胶的团聚，为开发用于能量转换系统的碳水凝胶材料开辟了新途径。
