摘要:
采用固相法首先制备前驱体,然后不同温度热处理得到α-Fe2O3纳米材料,采用XRD、FTIR、FESEM、DRS等多种表征手段分析了材料的晶体结构、微观形貌与光学性能。结果表明,热处理温度升高,α-Fe2O3纳米材料粒径逐渐增大,其带隙宽度也逐渐升高,但均小于体相α-Fe2O3的带隙宽度(2.2 eV)。500℃热处理2 h所得α-Fe2O3纳米材料具有最高的可见光光催化效率和光降解速率常数,其分别为70.60%和6.78 × 10−3 min−1,太高或太低的热处理温度均会导致光催化效率降低,这主要受带隙大小和电子–空穴复合机率影响。
Abstract:
Precursors were synthesized by a solid-state synthesis method. And α-Fe2O3 nanomaterials were obtained by thermal decomposition of precursors at different calcination temperatures. The crystal structure, microstructure morphology and optical properties of the α-Fe2O3 nanoparticles were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, Field scanning electron microscopy (FESEM), and UV-vis diffuse reflectance spectroscopy (DRS). The results show that the energy gap and particle size of the α-Fe2O3 nanomaterials increase with annealing temperature. But they are all less than bulk α-Fe2O3 (2.2 eV). The α-Fe2O3 nanoparticles prepared at 500˚C for 2 h exhibit the highest visible-light photocatalytic efficiency of 70.60% and photodegradation rate constant, k, of 6.78 × 10−3 min−1, respectively. Too high or too low heat treatment temperature will result in the decrease of photocatalytic efficiency, which is mainly affected by band gap and electron-hole recombination probability.
文章引用:王碧军, 刘劲松, 李子全, 黄洁文, 李云朋, 丛孟启, 冯冰, 陈建康, 朱孔军, 裘进浩. α-Fe
2O
3纳米材料的固相合成及光催化降解亚甲基蓝性能[J]. 纳米技术, 2016, 6(1): 14-21.
http://dx.doi.org/10.12677/NAT.2016.61003