Self-assembly flower-like porous carbon nanosheet powders for higher lithium-ion storage capacity

Layered g-C3N4@Reduced Graphene Oxide Composites as Anodes with Improved Rate Performance for Lithium-Ion Batteries

As important anodes in lithium-ion batteries, graphene is always faced with the aggregation problem that makes most of the active sites lose their function at high current densities, resulting in low Li-ion intercalation capacity and poor rate performance. To address this issue, a layered g-C₃N₄@reduced graphene oxide composite (g-C₃N₄@RGO) was prepared via a scalable and easy strategy. The resultant g-C₃N₄@RGO composite possesses large interlayer distances, rich N-active sites, and a microporous structure, which largely improves Li storage performance. It shows excellent cycle stability (899.3 mA h g^-1 after 350 cycles under 500 mA g^-1) and remarkable rate performance (595.1 mA h g^-1 after 1000 cycles under 1000 mA g^-1). Moreover, the g-C₃N₄@RGO electrode exhibits desired capacity retention and relatively high initial Coulombic efficiency of 58.8%. Impressively, this result is better than that of RGO (29.1%) and most of RGO-based anode materials reported in the literature. Especially, the g-C₃N₄@RGO-based electrode is enough to power two tandem red-light-emitting diodes and run a digital watch. Interestingly, the electronic watch can work continuously for more than 20 days. This novel strategy shows the great potential of g-C₃N₄@RGO composites as energy-storage materials.

Spray-Drying of Electrode Materials for Lithium- and Sodium-Ion Batteries

The performance of electrode materials in lithium-ion (Li-ion), sodium-ion (Na-ion) and related batteries depends not only on their chemical composition but also on their microstructure. The choice of a synthesis method is therefore of paramount importance. Amongst the wide variety of synthesis or shaping routes reported for an ever-increasing panel of compositions, spray-drying stands out as a versatile tool offering demonstrated potential for up-scaling to industrial quantities. In this review, we provide an overview of the rapidly increasing literature including both spray-drying of solutions and spray-drying of suspensions. We focus, in particular, on the chemical aspects of the formulation of the solution/suspension to be spray-dried. We also consider the post-processing of the spray-dried precursors and the resulting morphologies of granules. The review references more than 300 publications in tables where entries are listed based on final compound composition, starting materials, sources of carbon etc.

CTAB-assisted multiwalled carbon nanotube-loaded NaFe2Mn(PO4)3 materials as high performance cathodes for sodium-ion batteries

The electrochemical performance of NaFe₂Mn(PO₄)₃ materials has been improved by adding MWCNTs and CTAB.