Exfoliated graphene oxide (EG)/MoO2 composites are synthesized by a simple solid-state graphenothermal reduction method. Graphene oxide (GO) is used as a reducing agent to reduce MoO3 and as a source for EG. The formation of different submicron sized morphologies such as spheres, rods, flowers, etc., of monoclinic MoO2 on EG surfaces is confirmed by complementary characterization techniques. As-synthesized EG/MoO2 composite with a higher weight percentage of EG performed excellently as an anode material in lithium-ion batteries. The galvanostatic cycling studies aided with postcycling cyclic voltammetry and galvanostatic intermittent titrations followed by ex situ structural studies clearly indicate that Li intercalation into MoO2 is transformed into conversion upon aging at low current densities while intercalation mechanism is preferably taking place at higher current rates. The intercalation mechanism is found to be promising for steady-state capacity throughout the cycling because of excess graphene and higher current density even in the operating voltage window of 0.005-3.0 V in which MoO2 undergoes conversion below 0.8 V.

Biomineral matrix formation and molecular recognition are two important processes associated with eggshell biomineralization. To understand these two processes, a major intracrystalline peptide, pelovaterin, was isolated from turtle (Pelodiscus sinensis) eggshell and its tertiary and quaternary structures were established. The global fold of pelovaterin is similar to that of human beta-defensins but has a large hydrophobic core and a short hydrophilic N-terminal segment, which is not preserved in defensins. Pelovaterin exhibits strong antimicrobial activity against two pathogenic gram-negative bacteria, Pseudomonas aeruginosa and Proteus vulgaris, and stabilizes a thin film of metastable vaterite. We show that pelovaterin self-aggregates in the form of micellar nanospheres and the aggregation in solution is entropy-driven. It is suggested that the micellar aggregation of pelovaterin is responsible for the induction and stabilization of the metastable phase by altering the interfacial energy. The results demonstrate the adaptability of an extracellular matrix protein to perform multiple tasks: polymorph discrimination and protection of the contents of the egg against bacterial invasion.

We prepared solid solutions based on Ni, Zn and Fe-oxides to be used as nanomaterials for anodes of Li-ion batteries. The materials were synthesized using molten salt method with KCl as the molten salt. The prepared nano-materials (Ni 1-x Zn x )Fe 2 O 4 (x=0,0.25,0.5, 0.75, 1) were subsequently characterized by Scanning Electron Microscope (SEM), X-Ray Diffraction (XRD), the Brunauer-Emmett-Teller surface and density methods.Cyclic Voltammetry (CV) and Galvanostatic Cycling tests were then conducted to understand the Lithium storage performance of the electrodes. Electrochemical impedance spectroscopy (EIS) was also performed to analyse the kinetics of our electrodes and other characteristics of the battery cell. The electrochemical properties of prepared compounds showed reversible capacities (mAh/g) of 706, 819, 603, 781, 637 for x= 0, 0.25, 0.5, 0.75 and 1 at the end of the 50 th cycle.

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