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Phosphosilicate molecular precursor for the synthesis of NASICON, natrium super ionic conductor, Na 1+ xZr 2Si xP 3− xO 12( x= 1 and 2) has been devised and prepared by the hydrolysis of tetraethoxysilane (TEOS) employing sodium phosphate solution. The molecular precursor was reacted with Zr(OC 3H 7) 4in ethanol under solvolytic condition to yield nano precursor material of NASICON. This material was annealed at high temperature to yield phase-pure NASICON. The molecular precursor was characterized using 31P NMR, FTIR spectral data, powder XRD pattern and TG/DTA studies. The structure of the molecular precursor was deduced from the powder XRD data, which indicates the presence of edge sharing tetrahedral arrangement of −O−Si−O−P−O−Si− chain. The NASICON precursor material was characterized using TG/DTA, FTIR, TEM, SEM, MAS 31P NMR and XRD. The conductivity of the synthesized NASICON material was measured using the pellet annealed at 900 °C and was found to be 5.5 x10 −3S cm −1. The details on the preliminary investigation are presented in this paper. [ABSTRACT FROM AUTHOR]

A Prussian blue (PB) film was deposited on a glassy carbon (GC) electrode by cyclic voltammetry in the presence of the cationic surfactant cetyltrimethylammonium bromide (CTAB). The electrode thus formed showed 4-fold enhancements in redox current and charge values in pure KCl electrolyte as well as greater stability than an electrode prepared in the absence of CTAB. This improved performance of a PB CTAB electrode versus a PB electrode was further demonstrated using SEM, XRD, and electrochemical impedance spectroscopy (EIS) measurements. A comparative study was undertaken on the cation transport characteristics of PB and PB CTAB electrodes for Na, Li, and NH4ions. We obtained a CV pattern for a CTAB-promoted PB film, which showed ideal Nernstian behavior at all scan rates from 5 to 140 mV s-1. Conditions for the formation and preservation of these ideal and stable PB films are discussed. Possible mechanisms for the beneficial effects of CTAB are proposed. [ABSTRACT FROM AUTHOR]