Aluminum and titanium imidodiphosphates as single precursor molecules to aluminum and titanium phosphate materials

The aluminum and titanium imidodiphosphates compound,, respectively (1) und er bar and (2) under bar are efficient single-source precursors to homogene ous aluminum and titanium phosphates materials. The conversion occurs pyrol ytically at high temperature giving the corresponding compounds. Differenti al thermal and thermogravimetric analyses, P-31 and Al-27 MAS NMR, as well as vibrational spectroscopies were used to characterize the final materials . In the case of the aluminum compound (1) under bar it was found that the Al-27 MAS NMR signal representative of the octahedral aluminum observed in the material obtained at 900 degreesC was transformed to a signal character istic of a tetrahedrally aluminum by increasing the temperature to 1200 deg reesC, This was confirmed by P-31 MAS NMR and XPS studies. The thermal evol ution of (2) under bar was studied by using Raman spectroscopy. The convers ion of the phosphate material to TiO2 in the rutile phase after a thermal t reatment at 1400 degreesC during 3 hours was observed. The synthetic route to the phosphate materials described here could represent an alternative wa y to the sol-gel process and may offer certain advantages.