Suguna S, Shankar S, Jaganathan Saravana Kumar, Manikandan Ayyar
PG and Research Department of Chemistry, M.R. Govt. Arts College, Mannargudi 614001, Tamil Nadu, India.
PG and Research Department of Chemistry, A.V.V.M Sri Pushpam College, Poondi 613503, Tamil Nadu, India.
J Nanosci Nanotechnol. 2018 Feb 1;18(2):1019-1026. doi: 10.1166/jnn.2018.13960.
Ni-doped cobalt aluminate NixCo1-xAl2O4 (x = 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0) spinel nanoparticles were successfully synthesized by a simple microwave combustion method using urea as the fuel and as well as reducing agent. X-ray powder diffraction (XRD) was confirmed the formation of single phase, cubic spinel cobalt-nickel aluminate structure without any other impurities. Average crystallite sizes of the samples were found to be in the range of 18.93 nm to 21.47 nm by Scherrer's formula. Fourier transform infrared (FT-IR) spectral analysis was confirmed the corresponding functional groups of the M-O, Al-O and M-Al-O (M = Co and Ni) bonds of spinel NixCo1-xAl2O4 structure. Scanning electron microscope (SEM) and transmission electron microscope (TEM) images was confirmed the particle like nanostructured morphology. Energy band gap (Eg) value was calculated using UV-Visible diffuse reflectance spectra (DRS) and the Eg values increased with increasing Ni2+ dopant from x = 0.2 (3.58 eV) to x = 1.0 (4.15 eV). Vibrating sample magnetometer (VSM) measurements exposed that undoped and Ni-doped CoAl2O4 samples have superparamagnetic behavior and the magnetization (Ms) values were increased with increasing Ni2+ ions. Spinel NixCo1-xAl2O4 samples has been used for the catalytic oxidation of benzyl alcohol into benzaldehyde and was found that the sample Ni0.6Co0.4Al2O4 showed higher conversion 94.37% with 100% selectivity than other samples, which may be due to the smaller particle size and higher surface area.
采用简单的微波燃烧法，以尿素作为燃料和还原剂，成功合成了镍掺杂钴酸铝NixCo1-xAl2O4（x = 0.0、0.2、0.4、0.6、0.8和1.0）尖晶石纳米颗粒。X射线粉末衍射（XRD）证实形成了单相立方尖晶石钴镍铝酸盐结构，无任何其他杂质。通过谢乐公式发现样品的平均晶粒尺寸在18.93纳米至21.47纳米范围内。傅里叶变换红外（FT-IR）光谱分析证实了尖晶石NixCo1-xAl2O4结构中M-O、Al-O和M-Al-O（M = Co和Ni）键的相应官能团。扫描电子显微镜（SEM）和透射电子显微镜（TEM）图像证实了颗粒状纳米结构形态。利用紫外可见漫反射光谱（DRS）计算了能带隙（Eg）值，随着Ni2+掺杂量从x = 0.2（3.58 eV）增加到x = 1.0（4.15 eV），Eg值增大。振动样品磁强计（VSM）测量表明，未掺杂和Ni掺杂的CoAl2O4样品具有超顺磁性行为，并且磁化强度（Ms）值随着Ni2+离子的增加而增大。尖晶石NixCo1-xAl2O4样品已用于将苯甲醇催化氧化为苯甲醛，发现样品Ni0.6Co0.4Al2O4表现出比其他样品更高的转化率94.37%和100%的选择性，这可能是由于其较小的粒径和较高的表面积。
