Thiazolium Poly(ionic liquid)s: Synthesis and Application as Binder for Lithium-Ion Batteries

We report a synthetic route to thiazolium-type poly­(ionic liquid)­s (PILs), which can be applied as a polymeric binder in lithium-ion batteries. The ionic liquid monomers were first synthesized by quaternization reaction of 4-methyl-5-vinyl thiazole with methyl iodide, followed by anion exchange reactions to replace iodide by fluorinated anions to access a liquid state below 100 °C. Subsequently, these monomers bearing thiazolium cations in their structure underwent radical polymerizations in bulk to produce corresponding polymers. The dependence of solution and thermal properties of such monomeric and polymeric materials on the choice of the counteranion was investigated. Finally, the thiazolium-type PIL bearing a bis­(trifluoromethanesulfonyl)­imide (TFSI) anion was proven to be a high performance binder for lithium-ion battery electrodes

Facile Route to an Efficient NiO Supercapacitor with a Three-Dimensional Nanonetwork Morphology

NiO nanostructures with three distinct morphologies were fabricated by a sol–gel method and their morphology-dependent supercapacitor properties were exploited. The nanoflower- shaped NiO with a distinctive three-dimensional (3D) network and the highest pore volume shows the best supercapacitor properties. The nanopores in flower-shaped nanostructures, offering advantages in contact with and transport of the electrolyte, allow for 3D nanochannels in NiO structure, providing longer electron pathways. The XPS and EIS data of the NiO nanostructure confirm that the flower-shaped NiO, which has the lowest surface area among the three morphologies, was effectively optimized as a superior electrode and yielded the greatest pseudocapacitance. This study indicates that forming a 3D nanonetwork is a straightforward means of improving the electrochemical properties of a supercapacitor

Quantum Confinement and Its Related Effects on the Critical Size of GeO₂ Nanoparticles Anodes for Lithium Batteries

This work has been performed to determine the critical size of the GeO₂ nanoparticle for lithium battery anode applications and identify its quantum confinement and its related effects on the electrochemical performance. GeO₂ nanoparticles with different sizes of ∼2, ∼6, ∼10, and ∼35 nm were prepared by adjusting the reaction rate, controlling the reaction temperature and reactant concentration, and using different solvents. Among the different sizes of the GeO₂ nanoparticles, the ∼6 nm sized GeO₂ showed the best electrochemical performance. Unexpectedly smaller particles of the ∼2 nm sized GeO₂ showed the inferior electrochemical performances compared to those of the ∼6 nm sized one. This was due to the low electrical conductivity of the ∼2 nm sized GeO₂ caused by its quantum confinement effect, which is also related to the increase in the charge transfer resistance. Those characteristics of the smaller nanoparticles led to poor electrochemical performances, and their relationships were discussed