(1. 惠州學院 化學工程系，惠州 516007；
2. 中南大學 化學化工學院，長沙 410083)
摘 要: 以Bi(NO3)3·5H2O、NaVO3和La(NO3)3·5H2O為原料，以葡萄糖為結(jié)構(gòu)導向劑，通過水熱法制備La摻雜BiVO4微米球。采用XRD、XPS、SEM、FTIR、UV-Vis、BET、光催化技術(shù)等對產(chǎn)品進行了表征和分析。結(jié)果表明，采用葡萄糖(2.0 g)輔助水熱法能合成結(jié)晶度高且形貌規(guī)整的單斜白鎢礦La/BiVO4微米球，微米球直徑范圍為2~9 μm，均由尺寸為30~65 nm納米顆粒自組裝而成。相比BiVO4塊狀顆粒，球狀La/BiVO4的紫外-可見光吸收邊發(fā)生了稍許紅移，具有較小的能帶隙(＜2.4 eV)，其中，2.0%La/BiVO4(質(zhì)量分數(shù))微米球表現(xiàn)出最高的光催化活性，其速度常數(shù)k為5.63×10-2 min-1，可見光照射10 mg/L亞甲基藍溶液60 min時的光解率達100%。
關(guān)鍵字: La/BiVO4；微米球；水熱法；摻雜；光催化
（1. Department of Chemical Engineering, Huizhou University, Huizhou 516007, China;
2. School of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China）
Abstract:Using Bi(NO3)3·5H2O, NaVO3 and La(NO3)3·5H2O as raw materials, La-doped BiVO4 microspheres were characterized and analyzed by hydrothermal process with glucose as the template. The as-prepared samples were investigated by XRD, XPS, SEM, FTIR, UV-Vis, BET and photocatalysis techniques. The results reveal that uniform, well crystallized and microspherical La/BiVO4 monoclinic crystal with the diameter range of 2-9 μm, which is self-assembled by lots of nanoparticles with the size of 30-65 nm, can be obtained via a hydrothermal route assisted by 2.0 g glucose. Compared with BiVO4 irregular particles, La/BiVO4 microspheres show a little red shift in the absorption band, resulting in a narrowed band gap (＜2.4 eV). For 2.0% La/BiVO4 (mass fraction) microspheres, its photodegradation rate constant k is 5.63×10-2 min-1 and the best photocatalytic activity is found with a 100% degradation of methylene blue (MB) with a concentration of 10 mg/L under visible-light irradiation for 60 min.
Key words: La/BiVO4; microspheres; hydrothermal method; doping; photocatalysis
