Cernea M, Montanari G, Galassi C, Costa A L
National Institute for Materials Physics, PO Box MG-7, Bucharest, RO-77125, Romania.
Nanotechnology. 2006 Mar 28;17(6):1731-5. doi: 10.1088/0957-4484/17/6/031. Epub 2006 Feb 27.
Lanthanum and niobium doped PZT with composition (Pb0.93La0.07)[(Zr0.60Ti0.40)]0.9825Nb0.0175O3 (PZTLN) was prepared by the gel-combustion method. A precursor sol was obtained from lead nitrate, zirconyl nitrate, lanthanum oxide, peroxo-citrato-niobium and a peroxo-citrate complex of titanium isopropoxide as starting precursors. Various molar ratios of citrate/nitrate (CA/NO3(-) = 1.3, 0.36 and 0.09) were used to prepare very fine powders of PZTLN. The gels resulting from these sols were transformed into powders by an auto-combustion process at ≤400 °C. The powders consisted of rhombohedral PZT (PbZr0.60Ti0.40O3), pyrochlore (Pb2Ti2O6) and lead carbonate (Pb2O·CO3) phases. The pure rhombohedral phase is found in PZTLN pellets sintered at 1100 °C for all citrate/nitrate ratios. Titanium and niobium precursors were modified with peroxo radicals. During the gel-combustion reaction, the temperature of the gel increases, leading to lead evaporation. The loss of lead as well as the particle size increases as the CA/NO3(-) ratio decreases. The smallest grained powder (about 50 nm) was obtained with the ratio CA/NO3(-) equal to 0.09.
采用凝胶燃烧法制备了组成为(Pb0.93La0.07)[(Zr0.60Ti0.40)]0.9825Nb0.0175O3的镧和铌掺杂PZT（PZTLN）。以硝酸铅、硝酸氧锆、氧化镧、过氧柠檬酸铌和异丙醇钛的过氧柠檬酸盐配合物为起始前驱体，得到前驱体溶胶。使用不同的柠檬酸/硝酸盐摩尔比（CA/NO3(-)=1.3、0.36和0.09）来制备非常细的PZTLN粉末。这些溶胶产生的凝胶在≤400 °C通过自动燃烧过程转化为粉末。粉末由菱方相PZT（PbZr0.60Ti0.40O3）、焦绿石（Pb2Ti2O6）和碳酸铅（Pb2O·CO3）相组成。对于所有柠檬酸/硝酸盐比例，在1100 °C烧结的PZTLN圆片中发现了纯菱方相。钛和铌前驱体用过氧自由基进行了改性。在凝胶燃烧反应过程中，凝胶温度升高，导致铅蒸发。随着CA/NO3(-)比例降低，铅的损失以及粒径增大。CA/NO3(-)比例等于0.09时获得了最小粒度的粉末（约50纳米）。
