以Ta2O5,Nb2O3和KOH为原料,采用水热法合成边缘尺寸约100nm,厚约10 nm的KTa0.77Nb0.23O3(KTN)单品纳米片.X线衍射(XRD)结果表明,产物为立方相钙钛矿结构；X线荧光光谱(XRF)显示,纳米片中K、Ta和Nb的比例约为1:0.70:0.22,与KTa0.77Nb0.23O3化学计量比有轻微的偏移,这主要是KTN纳米片表面Ta元素强烈的自吸收引起的.室温拉曼光谱研究显示纳米片有8个声子振动峰,频率分别位于166,214,274,462,562,765,876和1 098 cm 1,较之块体散射峰发生了红移和较大的展宽,这可能是由于纳米片的表面应力或结构缺陷导致,如堆垛层错等.%KTa0.77Nb0.23 O3(KTN) single crystalline nanoplates with edge sizes of about 100 nm and thickness of about 10 nm had been synthesized by hydrothermal method using Ta2O5, Nb2O5 and KOH served as raw materials. X-ray diffraction (XRD) result showed that the samples had perovskite structure with cubic phase; X-ray fluorescence (XRF) spectrum exhibited that the resulting nanoplates contain ing K, Ta and Nb cations in a 1:0. 70: 0. 22 ratio, which was deviating from the stoichiometry of KTa0.77 Nb0.23 O3 slightly, which might be due to the strong self-absorption of Ta element in the surface of KTN nanoplates. Room temperature Raman spectrum of nanoplates revealed seven phonon vibration peaks, which located at 166,214,274,462,562,765,876 and 1 098 cm-1, respectively. The scattering profile was to be more diffused and enlarged comparing to that of bulk materials. This might be induced by the surface stress or structure defects, such as stacking faults.
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