Peng Lu, Doménech-Carbó Antonio, Primo Ana, García Hermenegildo
Instituto Universitario de Tecnología Química CSIC-UPV, Universitat Politècnica de Valencia Av. De los Naranjos s/n 46022 Valencia Spain
Departament de Química Analítica, Universitat de València Dr Moliner, 50, 46100 Burjassot València Spain.
Nanoscale Adv. 2019 Oct 21;1(12):4827-4833. doi: 10.1039/c9na00554d. eCollection 2019 Dec 3.
By applying the well-known templating mechanism employed for the synthesis of mesoporous silicas to the structuration of sodium alginate, a novel defective 3D tubular graphene material (graphenolite) with hierarchical macro/meso/micro-porous structure, very high powder specific surface area (1820 m g) and regular micropore size (0.6 nm) has been obtained. The key feature of the process is the filmogenic property of alginate that is able to replicate the liquid crystal rods formed by the CTAC template in the aqueous phase. The 3D graphene exhibits 2.5 times higher capacitance using Li electrolyte compared to K, indicating that Li can ingress to the ultramicropores which, in contrast, are not accessible to K. Electrochemical impedance measurements also indicate much lower resistance for Li in comparison to K electrolyte, confirming the benefits of controlled microporosity of 3D graphene granting selective access to Li, but not to K. The present report opens the door for the synthesis of a wide range of 3D graphene materials that could be prepared following similar strategies to those employed for the preparation of zeolites and periodic mesoporous aluminosilicates.
通过将用于合成介孔二氧化硅的著名模板机制应用于海藻酸钠的结构化,获得了一种新型的具有分级大孔/介孔/微孔结构、非常高的粉末比表面积(1820 m²/g)和规则微孔尺寸(0.6 nm)的有缺陷的三维管状石墨烯材料(石墨烯石)。该过程的关键特征是海藻酸钠的成膜特性,它能够复制由十六烷基三甲基氯化铵模板在水相中形成的液晶棒。与钾相比,使用锂电解质时三维石墨烯的电容高出2.5倍,这表明锂可以进入超微孔,而钾则无法进入。电化学阻抗测量还表明,与钾电解质相比,锂的电阻要低得多,这证实了三维石墨烯可控微孔性的好处,即允许锂选择性进入,但钾无法进入。本报告为合成多种三维石墨烯材料打开了大门,这些材料可以按照与制备沸石和周期性介孔硅铝酸盐类似的策略来制备。