Farooq Umar, Ahmed Jahangeer, Alshehri Saad M, Ahmad Tokeer
Nanochemistry Laboratory, Department of Chemistry, Jamia Millia Islamia, New Delhi 110025, India.
Department of Chemistry, College of Science, King Saud University, Riyadh 11451, Saudi Arabia.
ACS Omega. 2019 Nov 6;4(21):19408-19419. doi: 10.1021/acsomega.9b02830. eCollection 2019 Nov 19.
NaTaO nanoparticles with a high surface area of 46.2 m/g have been successfully synthesized using a polymeric citrate precursor route. As-prepared nanoparticles were extensively characterized by X-ray diffraction, Fourier transform infrared, transmission emission microscopy, and scanning electron microscopy studies for the analysis of phase purity, crystallinity, and morphology. NaTaO nanoparticles show efficient photo-induced removal of the methylene blue dye under sunlight, which were confirmed by using liquid chromatography-mass spectroscopy. 86% dye has been degraded in 200 min at neutral pH, whereas the same amount of dye was decolorized in only 80 min at alkaline pH. Also, the dielectric behavior of the as-prepared nanoparticles at different annealing temperatures was explained by the Maxwell-Wagner polarization mechanism. At 500, 600, and 700 °C annealing temperatures, the dielectric constant and dielectric loss at 500 kHz for the samples were found to be 21.5, 18, and 16 and 0.012, 0.022, and 0.029, respectively. The unsaturated hysteresis loop shows weak ferroelectric behavior of NaTaO nanoparticles with remanent and saturation polarizations of 0.0013 and 0.21 μC/cm, respectively, and S-E hysteresis shows a bipolar strain of 0.10%.
采用聚合柠檬酸盐前驱体路线成功合成了比表面积高达46.2 m²/g的NaTaO纳米颗粒。通过X射线衍射、傅里叶变换红外光谱、透射发射显微镜和扫描电子显微镜研究对制备的纳米颗粒进行了广泛表征,以分析相纯度、结晶度和形态。NaTaO纳米颗粒在阳光下显示出对亚甲基蓝染料的高效光致去除效果,这通过液相色谱-质谱法得到证实。在中性pH条件下,86%的染料在200分钟内被降解,而在碱性pH条件下,相同量的染料仅在80分钟内就被脱色。此外,通过麦克斯韦-瓦格纳极化机制解释了制备的纳米颗粒在不同退火温度下的介电行为。在500、600和700°C的退火温度下,样品在500 kHz时的介电常数和介电损耗分别为21.5、18和16以及0.012、0.022和0.029。不饱和磁滞回线显示NaTaO纳米颗粒具有弱铁电行为,剩余极化和饱和极化分别为0.0013和0.21 μC/cm²,而S-E磁滞显示双极应变0.10%。