Khan Abrar Amin, Rabi Sazid Noor, Jamee Tousif, Galib Musanna, Elahi Fazle, Rahman Md Ashiqur
Department of Mechanical Engineering, Bangladesh University of Engineering and Technology, Dhaka 1000, Bangladesh.
Department of Mechanical Engineering, The University of British Columbia, Vancouver V6T 1Z4, Canada.
J Phys Chem B. 2024 Oct 3;128(39):9586-9597. doi: 10.1021/acs.jpcb.4c04097. Epub 2024 Sep 23.
The performance characteristics of supercapacitors composed of crumpled graphene electrodes and aqueous NaCl electrolytes are investigated through Molecular Dynamics (MD) simulations using a newly developed crumpled graphene-based supercapacitor model. Results suggest that the three-dimensional configuration of crumpled graphene boosts electrolyte-electrode interaction. This improved interaction, which includes a larger ion-accessible zone, increases the specific capacitance of the supercapacitor by roughly 400% (16.4 μF/cm) compared to planar graphene electrodes. Examining the effect of different stages of crumpling and the inclusion of pores on the electrode surface shows that the stages of crumpling substantially influence the supercapacitor performance. A smaller crumpling radius, meaning fully crumpled stage, improves the performance as increased crumpling leads to better packing efficiency, which aids in more ion separation. Furthermore, adding pores on the surface of crumpled graphene improves the ion accessibility by creating additional adsorption sites. An exceptional capacitance of 19.8 μF/cm is obtained for a porosity of 20%. However, the results suggest that the in-plane-porosity of the electrode needs to be optimized as there is a decline in specific capacitance after that point (20% porosity), indicating a suboptimal relationship between the charge distribution, specific surface area (SSA) and the porosity of the electrode.
通过使用新开发的基于皱折石墨烯的超级电容器模型进行分子动力学（MD）模拟，研究了由皱折石墨烯电极和水性NaCl电解质组成的超级电容器的性能特征。结果表明，皱折石墨烯的三维结构增强了电解质与电极之间的相互作用。这种改善的相互作用，包括更大的离子可及区域，与平面石墨烯电极相比，使超级电容器的比电容增加了约400%（16.4 μF/cm）。研究不同皱折阶段以及电极表面孔隙的存在对超级电容器性能的影响表明，皱折阶段对超级电容器性能有显著影响。较小的皱折半径，即完全皱折阶段，会提高性能，因为皱折程度增加会导致更好的堆积效率，有助于更多的离子分离。此外，在皱折石墨烯表面添加孔隙通过创造额外的吸附位点提高了离子可及性。对于20%的孔隙率，获得了19.8 μF/cm的优异电容。然而，结果表明电极的面内孔隙率需要优化，因为在该点（20%孔隙率）之后比电容会下降，这表明电荷分布、比表面积（SSA）和电极孔隙率之间存在次优关系。
