LEAD PYRONIOBATE PYROCHLORE NANOPARTICLES SYNTHESIZED VIA HYDROTHERMAL PROCESSING

Ultrafine lead pyroniobate Pb2Nb2O7 particles were successfully prepar ed via hydrothermal processing. When the lead nitrate and niobium hydr ogenoxalate solutions were utilized as the starting materials, the PbC 2O4 precipitates formed hindered the synthesis of Pb2Nb2O7. On the oth er hand, adding ammonia to the lead nitrate solution suppressed the fo rmation of PbC2O4 while the formation rate of Pb2Nb2O7 was significant ly accelerated. Monophasic Pb2Nb2O7 was obtained at temperatures as lo w as 150 degrees C. The particle size of hydrothermally synthesized po wders, compared to that of powders produced by the traditional solid s tate reaction, was profoundly reduced to the nanometer order (around 1 0-20 nm). Copyright (C) 1997 Elsevier Science Ltd.