摘要
采用聚丙烯酰胺凝胶法制备了TbFeO3纳米颗粒,研究了不同络合剂对样品的纯度、颗粒尺寸及形貌的影响.XRD分析结果表明,以酒石酸、柠檬酸或乙二胺四乙酸(EDTA)为络合剂,在650℃下烧结均可制备出单相TbFeO3纳米颗粒,但产物的平均粒径不同;而采用乙酸或草酸为络合剂则难以制得纯相样品.SEM观测结果表明,以酒石酸为络合剂制备的颗粒细小、均匀、形貌规整、呈球状,平均粒径约为50 nm;以柠檬酸为络合剂制备的颗粒主要以近球形为主,颗粒的尺寸分布相对较宽,平均粒径约为100 nm;以EDTA为络合剂制备的颗粒主要呈椭球状,颗粒尺寸较均匀,但颗粒间存在不同程度的黏连现象,平均粒径约为110 nm.这3种样品的BET比表面积分别为15.4,8.3和6.8 m2/g.紫外-可见漫反射吸收光谱研究表明,TbFeO3纳米颗粒的带隙为1.95～1.98 eV.分别以甲基橙(MO)、罗丹明B(RhB)、亚甲基蓝(MB)、酸性品红(AF)和刚果红(CR)5种有机染料为目标降解物,考察了TbFeO3颗粒的光催化活性.结果表明,在可见光辐照下颗粒表现出良好的光催化活性,其中,以酒石酸为络合剂制备的样品光催化效果最好.
A polyacrylamide gel method was used to prepare TbFeO3 nanoparticles,and the influences of diffe-rent chelating agents on the phase purity,particle size and morphology were investigated.X-ray diffraction（XRD） results indicate that single-phase TbFeO3 particles can be prepared at a calcination temperature of 650 ℃ using tartaric acid,citric acid or ethylenediamine-tetraacetic acid（EDTA） as the chelating agent,but the average grain size has a dependence on the choice of the chelating agent.The use of acetic acid or oxalic acid as the chelating agent is difficult to achieve the synthesis of single-phase TbFeO3 samples.Scanning electron microscope（SEM） observations reveal that the particles prepared using tartaric acid as the chelating agent are regularly spherical in shape and highly uniform in size with a small average diameter of ca.50 nm;the particles prepared using citric acid as the chelating agent mainly exhibit sphere-like shape and have a relatively broad size distribution with an average size of ca.100 nm;and the particles prepared using the chelating agent EDTA are ellipsoid-like in shaped with adhesive behavior to some extent,but have a uniform size distribution with an average size of ca.110 nm.The BET specific surface areas of the three samples are 15.4,8.3 and 6.8 m2/g,respectively.Ultraviolet-visible diffuse reflectance absorption spectra indicate that the TbFeO3 nanoparticles have a bandgap energy of 1.95—1.98 eV.The photocatalytic activity of the TbFeO3 particles has been investigated by the degradation of various organic dyes including methyl orange（MO）,rhodamine B（RhB）,methylene blue（MB）,acid fuchsine（AF）,and congo red（CR）.It is demonstrated that the products exhibit a pronounced photocatalytic activity under visible-light irradiation.The highest photocatalytic efficiency is observed for the tartaric acid-derived sample.
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
2012年第7期1565-1571,共7页
Chemical Journal of Chinese Universities
基金
国家自然科学基金(批准号:50962009)
教育部重点项目(批准号:209130)
甘肃省自然科学基金(批准号:1010RJZA041)
兰州理工大学优秀青年基金(批准号:Q200902)资助
