磁性NiFe2O4的制备与光催化性能及反应机理的研究

Study on preparation and photocatalytic properties and reaction mechanism of magnetic nickel ferrite

铁酸镍(NiFe_2O_4)是一种新型的、具有开发潜力的磁性催化剂。本文利用水热法,结合正交实验的原理,通过控制反应条件,制备出一系列(9组)NiFe_2O_4。采用紫外-可见漫反射、X射线衍射扫描、高倍扫描电镜等技术手段,对NiFe_2O_4的光催化能力、晶型、表面形貌等特性进行了表征。综合评价后,确定了具有最优光催化性能的铁酸镍(表观速率常数kapp为5.87×10^(-2)min^(-1))其水热制备条件为NaOH浓度为8.0mol·L^(-1),前驱液pH值为10,水热温度为200℃,水热时间为6h。与此同时,我们对铁酸镍的光催化机理进行了深入研究,发现影响其光催化的活性物种为·OH与h+,并建立了铁酸镍的光催化反应模型。

Nickel ferrite （NiFe2O4） is a new type of magnetic catalyst, which has development potential. In this paper, we used hydrothermal method, combined with the principle of orthogonal experiment, successfully made a series of NiFe2O4 by controlling the reaction conditions. The photocatalytic ability, crystal type, and crystal morphol- ogy characteristics of NiFe2O4 were studied by UV-Vis diffuse reflectance, X-ray diffraction scans, high magnifica- tion scanning electron microscope and other technical means. After comprehensive evaluation, The optimum photo- catalytic performance of nickel ferrite （kapp was 5.87x10-2 min-1） was determined, and its hydrothermal conditions were that NaOH concentration is 8.0 tool·L-1, precursor solution pH value was 10, hydrothermal temperature was 200℃ and hydrothermal time was 6 h. At the same time, the photocatalytic mechanism of nickel ferrite has been studied in depth, we discovered that the photocatalytic activity of the species was affected by ·OH, as well as h＋, based on this we established the photocatalytic reaction model of nickel ferrite.