纳米LaFeO_3溶胶凝胶合成、表征及性能研究

Characterization and capability research on preparation of nano-LaFeO_3 by sol-gel method

以硝酸铁和硝酸镧为无机源,嵌段聚合物F-127为表面活性剂,利用一种简单的溶胶-凝胶法合成了纳米铁酸镧,通过XRD、IR、TG-DTA、BET等对样品进行了表征。对样品的可见光催化活性进行了测试,在光催化降解罗丹明B实验中,发现焙烧500℃的铁酸镧样品光催化活性好于400℃焙烧的样品。XRD测试表明,焙烧温度为400℃时铁酸镧形成,随着焙烧温度的增加XRD衍射峰强度稍有增加,同时杂质峰变弱。氮气吸附脱附测试样品的比表面积为55.1 m2/g。

Nanoerystalline LaFeO3 has been synthesized using La （ NO3 ） 3 ·6H2O and Fe （ NO3 ） 3 ·9 H2O as the inorganic precursors, triblock copolymer pluronic F-127 as the surfactant by the method of sol-gel. The nano-LaFeO3 sample was characterized by XRD, IR, TG-DTA, BET. The sample activity of different LaFeO3 nanoparticles for degrading Rhodamine B solution under visible irradiation （ k 〉 400 nm） was evaluated. The effects photocatalytic activity was mainly investigated. The results show that the LaFeO3 sample calcined at 500 ℃ exhibits higher activity. Resuhs indicated that LaFeO3 nanoparticles could be formed when calcined at 400 ℃. X-ray diffraction peaks is enhanced with the increasing of calcined temperature, which indicate the crystalline became more perfect. The specific surface area determined by BET surface area measurement was found to be 55.1 m^2/g.