Fully activated Li 2 MnO 3 nanoparticles were prepared by a chemical based oxidation reaction. All of the diffraction peaks of the prepared samples were well matched to a monoclinic phase (space group: C2/m) with no impurity peaks and refined using the General Structure Analysis System (GSAS) program. The activated Li 2 MnO 3 sample showed homogeneously well-dispersed nanoparticles with a size of $10 nm. The oxidation state of Mn was confirmed by XPS. The activated Li 2 MnO 3 nanoparticles delivered a high charge capacity of 302 mA h g À1 above 4.5 V and discharge capacity of 236 mA h g À1 during the first cycle. Interestingly, the cycle performance of the activated Li 2 MnO 3 nanoparticles during extended cycles exhibited somewhat stable discharge capacities without any drastic capacity fading, even when cycled in the high voltage range of 2.0-4.9 V and after the phase transition to spinel. In terms of the rate performance, the activated Li 2 MnO 3 sample exhibited significantly superior properties compared to the bulk Li 2 MnO 3 sample, probably due to the nano-size particles with high crystallinity.

Despite nanomaterials with unique properties playing a vital role in scientific and technological advancements of various fields including chemical and electrochemical applications, the scope for exploration of nano-scale applications is still wide open. The intimate correlation between material properties and synthesis in combination with the urgency to enhance the empirical understanding of nanomaterials demand the evolution of new strategies to promising materials. Herein we introduce a rapid pyro-synthesis that produces highly crystalline functional nanomaterials under reaction times of a few seconds in open-air conditions. The versatile technique may facilitate the development of a variety of nanomaterials and, in particular, carbon-coated metal phosphates with appreciable physico-chemical properties benefiting energy storage applications. The present strategy may present opportunities to develop “design rules” not only to produce nanomaterials for various applications but also to realize cost-effective and simple nanomaterial production beyond lab-scale limitations.

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Li 4 Ti 5 O 12 was successfully synthesized by solvothermal techniques using cost-effective precursors in polyol medium. The x-ray diffraction ͑XRD͒ pattern of the sample ͑LTO-500͒ was clearly indexed to the spinel shaped Li 4 Ti 5 O 12 and in order to accurately determine the lattice parameters, synchrotron powder XRD pattern was fitted by the whole-pattern profile matching method using the model space group, Fd3m. The particle size, morphology, and crystallinity of LTO-500 were identified using field-emission scanning electron microscopy and transmission electron microscopy. The electrochemical performance of the sample revealed fairly high initial discharge/charge specific capacities of 230 and 179 mAh/g, respectively, and exhibited highly improved rate performances at C-rates as high as 30 and 60 C, when compared to Li 4 Ti 5 O 12 by the solid-state reaction method. This was attributed to the achievement of small particle sizes in nanoscale dimensions, a reasonably narrow particle size distribution and, hence, shorter diffusion paths combined with larger contact area at the electrode/electrolyte interface.

Reduced graphene oxide (rGO) sheets were synthesized by a modified Hummer's method without additional reducing procedures, such as chemical and thermal treatment, by appropriate drying of graphite oxide under ambient atmosphere. The use of a moderate drying temperature (250°C) led to mesoporous characteristics with enhanced electrochemical activity, as confirmed by electron microscopy and N 2 adsorption studies. The dimensions of the sheets ranged from nanometres to micrometres and these sheets were entangled with each other. These morphological features of rGO tend to facilitate the movement of guest ions larger than Li + . Impressive electrochemical properties were achieved with the rGO electrodes using various charge-transfer ions, such as Li + , Na + and K + , along with high porosity. Notably, the feasibility of this system as the carbonaceous anode material for sodium battery systems is demonstrated. Furthermore, the results also suggest that the high-rate capability of the present rGO electrode can pave the way for improving the full cell characteristics, especially for preventing the potential drop in sodium-ion batteries and potassium-ion batteries, which are expected to replace the lithium-ion battery system