The rational design of inorganic and organic material based nanocomposite hybrids as Na-ion battery electrodes

Abstract

The past decade has witnessed a significant research interest on rechargeable Na-ion batteries (SIBs). Compared to Li-ion batteries, SIBs promise to be much more cost-effective, thanks to the high abundance...

Recent progress in quantum dots based nanocomposite electrodes for rechargeable monovalent metal-ion and lithium metal batteries

“…Modifying the micro/nano-structure active materials with conductive carbon with strong interaction between them has been a widely practiced strategy to improve the electronic conductivity and structural durability of composite electrodes. 6,32,121 However, engineered carbon with controlled size (<10 nm) has added advantages compared to its larger counterpart in terms of controlling the uniform coating without agglomeration and modifying the interfacial chemistry. By definition, they can be divided into three categories: (i) carbon (nano) dots or CDs which are amorphous with no quantum confinement, (ii) CQDs which are crystalline, have quantum confinement and spherical, and (iii) GQDs which are crystalline, two dimensional with quantum confinement.…”

“…3,4 This has triggered a significant research interest in improving the electrochemical performance of the electrodes and electrolytes of the existing LIBs to meet the immediate demand, as well as in exploring other rechargeable battery chemistries beyond Li-ion for applications where the battery cost and maintenance are rather more important factors than the energy density. 5–10…”

“…The electrode material should have a high theoretical capacity, large electrolyte accessible active sites for charge storage, should be porous for the electrolyte infiltration, should have good conductivity for facile charge transport and structural integrity and flexibility to buffer the volume change during cycling, and overall be cost effective. 6,30…”

“…Over the years, several organic and inorganic materials with high theoretical capacities have been explored in this direction. 6,31 However, irrespective of the metal ion charge carrier, the major barriers against reaching the theoretical capacities of different electrode materials are mainly the insulating nature of the majority of the conventional electrode materials, inaccessible electrochemically active surface area and huge volume change involved with the rocking chair mechanism, which lead to structural degradation and quick capacity fading.…”

“…On the other hand, the rational designing is aimed at maximizing the electrolyte accessible surface area, controlling the porosity, improving the electronic conductivity, and providing structural integrity and flexibility within the electrode architecture. 6,32…”