Fig. 1. Schematic diagram of experimental device for nano ZnO crystallization under high voltage DC electric field.高压直流电场条件下纳米氧化锌晶化实验装置示意图

Fig. 2. XRD patterns of nano-ZnO synthesized for different time: (a) Without external electric field; (b) under external electric field不同晶化时间纳米氧化锌的XRD图谱.　(a)无外电场; (b)有外电场

Fig. 3. XRD patterns of nano-ZnO synthesized at different temperatures: (a) Without external electric field; (b) under external electric field.不同晶化温度所得纳米氧化锌的XRD图谱　(a)无外电场; (b)有外电场

Fig. 4. Microphotographs of nano-ZnO synthesized under different electric field intensities: (a) 1 kV/cm; (b) 4 kV/cm; (c) 6 kV/cm; (d) 7 kV/cm不同电场强度下合成纳米氧化锌的显微形貌　(a)1 kV/cm; (b)4 kV/cm; (c)6 kV/cm; (d)7 kV/cm

Fig. 5. Raman spectra of polarized nano-ZnO: (a) Cathode surface; (b) anode surface.纳米氧化锌极化产物的拉曼光谱图　(a)阴极面; (b)阳极面

Fig. 6. Relationship of leakage current, and 1050 cm^–1 Raman intensity with electric intensity 漏电电流及拉曼峰1050 cm^–1强度与电场强度之间的关系

Fig. 7. Relationship of strength ratio of Raman peak I₁(438 cm^–1)/I₂(1050 cm^–1) with electric field intensity. 拉曼峰438 cm^–1和1050 cm^–1的强度比(I₁/I₂)与电场强度的关系

Fig. 8. Changes of Raman spectra of nano-ZnO after secondary reverse polarization二次反向极化后纳米氧化锌拉曼图谱的变化