摘要
铁酸镧(LaFeO_(3))属钙钛矿型氧化物,具有良好的光催化活性、磁性和化学稳定性。采用超声辅助溶剂热法,通过调节水/丙三醇混合溶剂配比合成结晶度良好、表观粒径介于200 nm~1μm的LaFeO_(3)多孔微球,在紫外光(UV)下共激发过二硫酸盐(PDS),构建UV/LaFeO_(3)/PDS复合体系用以降活性黑五(RB5)。结果表明:LaFeO_(3)投加量0.5 g·L^(-1),PDS浓度为0.5 mmol·L^(-1),RB5初始浓度为20 mg·L^(-1),pH为初始值(p H=5.6)时,在25 W紫外灯照射下体系50 min对RB5的降解率可达98.19%。pH变化对RB5的去除率影响不大,但溶液偏酸时反应速率常数最大,碱性次之,中性最小。PDS对光生电子的捕获促进了光生电子-空穴对的分离,是光催化和PDS高级氧化产生协同作用的主要原因。^(1)O_(2),SO_(4)^(-)·和·OH 3种活性物质共存于UV/LaFeO_(3)/PDS体系使得RB5快速、高效降解。
LaFeO_(3) is a kind of perovskite oxide with excellent photocatalytic activity,magnetic and chemical stability.By adjusting the ratio of water and glycerol mixed solvent,LaFeO_(3) with favourable crystallinity was synthesized using ultrasonic-assisted solvothermal method.LaFeO_(3) was used as the catalyst to activate persulfacte(PDS)under ultraviolet light for the degradation of reactive black 5(RB5).Results indicate that 98.19%of RB5 can be degraded with the addition of 0.5 g∙L^(-1) LaFeO_(3) and 0.5 mmol∙L^(-1) PDS within 50 min in the presence of 25 W UV light when initial solution PH and RB5 concentrations are 5.6 and 20 mg∙L^(-1),respectively.The degradation efficiency of RB5 is maintained in a wide range of initial pH.However,the reaction rate constant under acidic condition achieves maximum value compared to alkaline and neutral condition.The trapping of photogenerated electrons by PDS promotes the separation of photogenerated electrons and holes,which is the main driving factor for the synergistic effects between photocatalysis and advanced oxidation based on SO^(-)_(4)·.^(1)O_(2),SO^(-)_(4)·and·OH generated during the catalysis is proposed for the rapid and efficient degradation of RB5 in UV/LaFeO_(3)/PDS system.
作者
樊健
王洋洋
王飞
孙莹莹
张连科
韩剑宏
Fan Jian;Wang Yangyang;Wang Fei;Sun Yingying;Zhang Lianke;Han Jianhong(School of Energy and Environment,Inner Mongolia University of Science and Technology,Baotou 014010,China;College of Energy Power and Mechanical Engineering,North China Electric Pow-er University,Beijing 102206,China;Comprehensive Security Center of Baotou Ecological Envi-ronment Bureau,Baotou 014010,China)
出处
《中国稀土学报》
EI
CAS
CSCD
北大核心
2023年第6期1061-1070,I0002,共11页
Journal of the Chinese Society of Rare Earths
基金
内蒙古自然科学基金项目(2021LHMS04003)
内蒙古自然科学基金项目(2019LH02006)资助。
关键词
紫外光
铁酸镧
过硫酸盐
协同作用
活性黑五
ultraviolet light
LaFeO_(3)
persulfacte
synergistic effects
RB5
