MXene是一种新型二维过渡金属碳/氮化物,具有优异电化学性能的赝电容型超级电容器电极材料。本研究尝试用同步氨化/碳化制备MXene平面多孔电极。以滤纸为多孔平面模板,通过浸渍-烘干的手段把MXene固定在滤纸的纤维上,然后在氨气的气氛中热处理,得到了MXene/C平面多孔复合电极。分析结果表明:MXene纳米片均匀包覆在由滤纸碳化形成的碳纤维上。当浸渍5次时,在2 m V/s的扫速下测试,制备出的复合电极的面积比电容达到403 m F/cm2。在电流密度为10 m A/cm2下进行恒流充放电循环测试2500次后,比电容仍然与初始电容几乎相同,表现出良好的倍率性能和循环稳定性。在不使用高分子粘合剂和金属集流体的情况下,同步氨化/碳化法制备出的MXene/C平面多孔复合电极表现出优良的电化学性能。 相似文献
Two dimensional (2D) nanomaterials are promising fundamental building blocks for use in the next-generation semiconductor industry due to their unique geometry and excellent (opto)-electronic properties. However, large scale high quality fabrication of 2D nanomaterials remains challenging. Thus, the development of controllable fabrication methods for 2D materials is essential for their future practical application. In this review, we will discuss the importance of the space-confined vapor deposition strategy in the controllable fabrication of 2D materials and summarize recent progress in the utilization of this strategy for the synthesis of novel materials or structures. Using this method, various high quality ultrathin 2D materials, including large-area graphene and boron nitride, ReS2/ReSe2, HfS2, pyramid-structured multilayer MoS2, and the topological insulators Bi2Se3 and Bi2Te3, have been successfully obtained. Additionally, by utilizing van der Waals epitaxy growth substrates such as mica or other 2D materials, patterned growth of 2D nanomaterials can be easily achieved via a surface-induced growth mechanism. Finally, we provide a short prospect for future development of this strategy.
The preparation and the Czochralski growth of single crystals of PtSb2 by a liquid encapsulation technique is described. Conductivity and Hall effect measurements have been made in the temperature range 20 to 300° K. It is found that the material is n-type, with a carrier concentration of about 6 × 1016/cm3, the ratio of electron to hole mobility,
e/
h, is 0.57 at 110° K, and the electron mobility has a maximum value of 2100 cm2/V sec at 50° K. The thermal energy gap is 0.112 eV. 相似文献
Results are shown of an experimental study concerning the hygroscopic properties of cellulose materials for electrical insulation under low water vapor pressure.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 24, No. 5, pp. 868–875, May, 1973. 相似文献
Hydrogen storage and electrical properties of different hyperbranched polymer systems beside a nanocomposite are studied. The polymers examined are aliphatic hyperbranched poly urea (P-Urea), polyamide amine (PAMAM) and polyamide amine/vanadium oxide (PAMAM/VOx) nanocomposite. At 80 K and up to 20 bar hydrogen pressure, the hydrogen storage capacity of hyperbranched P-Urea reached 1.6 wt%, 0.9 wt% in case of PAMAM and 0.6 wt% for VOx. The hydrogen storage capacity significantly enhanced when PAMAM and VOx form a nanocomposite and increased up to 2 wt%. At 298 K and up to 20 bar, all the samples did not show measurable hydrogen uptake. Electrical properties of the samples are also investigated; the measurements showed complete insulating behavior at hydrogenation measuring temperature. These investigations ensure that the polymer conductivity does not play a role in hydrogen uptake, also hyperbranched polymers are promising materials for hydrogen storage. 相似文献