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A new phase of amorphous zirconium phosphate (ZrP), an inorganic ion exchanger of the class of tetravalent metal acid (TMA) salt, is synthesized by sol-gel method. The protons present in the structural hydroxyl groups indicate good potential for TMA salts to exhibit solid state proton conduction. Cu 2+ and Li + are exchanged onto ZrP to yield CuZrP and LiZrP exchanged phases. All these materials were characterized for elemental analysis (ICP-AES), thermal analysis (TGA, DSC), X-ray analysis and FTIR spectroscopy. The transport properties of these materials were explored and compared by measuring conductance at different temperatures using an impedance analyser. It is observed that conductivity decreases with increasing temperature in all cases and mechanism of transportation is proposed to be Grotthuss type. Conductivity performance of ZrP, CuZrP and LiZrP is discussed based on conductivity data and activation energy.

Amorphous zirconium titanium phosphate (ZTPA), an advanced inorganic ion exchanger of the class of tetravalent bimetallic acid (TBMA) salt, has been synthesized by sol gel route. ZTPA has been characterized by inductively coupled plasma atomic emission spectrometer (ICP-AES), Thermal analysis, Fourier transform infrared spectrometer (FTIR), and X-ray diffraction (XRD). The acid sites present in ZTPA indicate good potential to be explored as solid acid catalyst. The catalytic characteristics of ZTPA have been evaluated by determining surface area and surface acidity. The catalytic performance of ZTPA as a solid acid catalyst has been explored by studying esterification as a model reaction wherein mono and diesters have been synthesized. Crystalline zirconium titanium phosphate as well as amorphous and crystalline phases of zirconium phosphate and titanium phosphate have also been synthesized, characterized, and their catalytic performance investigated for comparative studies. TBMA salt exhibits enhanced catalytic activity compared to its single salt counterparts and amorphous phases exhibit higher catalytic activity compared to their crystalline phases.

Novel hybrid material, zirconium titanium hydroxy ethylidene diphosphonate (ZTHEDP) of the class of tetravalent bimetallic acid (TBMA) salt was synthesized using sol-gel route. ZTHEDP was characterized for elemental analysis (zirconium, titanium and phosphorus by ICP-AES and carbon and hydrogen by CHN analyzer), spectral analysis (FTIR), thermal analysis (TGA), Xray diffraction studies and SEM. Chemical resistivity of this material was assessed in various media-acids, bases and organic solvents. The protons present in the structural hydroxyl groups in ZTHEDP indicate good potential to exhibit solid state proton conduction. The proton transport property of ZTHEDP was explored by measuring specific conductance at different temperatures in the range of 303-423 K at 10 K intervals, using Solartron Impedance Analyzer (SI 1260) over a frequency range 1 Hz-32 MHz at a signal level below 1 V. Zirconium hydroxy ethylidene diphosphonate (ZrHEDP) and titanium hydroxy ethylidene diphosphonate (TiHEDP) were also synthesized under identical conditions, characterized and their proton transport properties investigated for comparative studies. It is observed that, in all cases, conductivity decreases with increasing temperature. Conductivity performance of ZTHEDP, ZrHEDP and TiHEDP is discussed based on conductivity data and activation energy. It is observed that, ZTHEDP exhibits enhanced conductance and the mechanism of transportation is proposed to be Grotthuss type.