| Metallic 2D Materials for Energy Storage Manish Chhowalla1; 1UNIVERSITY OF CAMBRIDGE, Cambridge, United Kingdom; PAPER: 406/Battery/Plenary (Oral) SCHEDULED: 17:50/Fri. 25 Oct. 2019/Coralino ABSTRACT: Two dimensional (2D) materials provide well-defined ion diffusion pathways for sodium and other ions, facilitating ion insertion and movement, which is difficult to achieve in conventional 3D electrode materials. As a result, high power densities can be achieved in 2D electrodes with rapid ion and electron transport. Although heavier than lithium, Na+ and K+ have key advantages in addition to their lower price – their lower desolvation energy, compared to smaller Li+, improves kinetics of ion insertion into the electrode and may lead to higher power. Multivalent ions, such as Mg2+ and Al3+, may store 2 – 3 electrons per ion, but their movement in 3D bulk or porous solids is restricted due to the limited lattice space, leading to slow charge/discharge processes and inferior stability of charge storage devices. Metallic 2D materials offer distinct advantages for battery electrodes. They are: i) highly conductive, with high density of states at the Fermi level and metal-like carrier densities; ii) chemically diverse and tailorable, allowing for systematic variation of both their intrinsic composition and their post-synthetically modified surface chemistry; iii) exceptionally rigid, with bending stiffness values comparable to graphene that are ideally suited for flexible energy storage devices; and iv) hydrophilic, allowing for co-assembly with polar species and enabling sustainable, green processability. These attributes make them especially promising for next-generation of rechargeable batteries with improved storage capability, faster charging and much longer lifetimes, even when combined with larger and higher charged ions. In this presentation, I will present our recent progress on synthesis of battery electrodes with metallic 2D materials and their performance as supercapacitors, electrochemical actuators and batteries. |
