摘要
太阳能光催化处理制药废水是缓解环境问题和能源危机的一种很有前途的方法.然而,提高其处理效率面临众多挑战,如光吸收效率低、光生载流子快速复合和光氧化还原电位低等.本文通过在BiOBr(BOB)微球上沉积碳量子点(CDs)和四(4-羧基苯基)卟啉(TCPP),巧妙地构建了TCPP/CDs/BOB有机/无机三元S型异质结,用于在可见光下有效降解水体中的盐酸四环素(TC).研究发现,由于两者之间的费米能级差异,在形成异质结时触发了电子从TCPP传递到BOB,从而在界面处构建内部电场(IEF).这极大推动了光诱导载流子的有效分离.此外,CDs作为电子收集器进一步提高了S型异质结的载流子分离能力,因此保留了在CDs中聚集更强还原能力的光电子和在BOB价带中更强氧化能力的空穴来参与光催化反应.在这些催化剂中,TCPP/CDs/BOB-2异质结催化剂在40 min内对TC的降解能力高达83.6%.TCPP/CDs/BOB-2的反应速率常数(k)分别约为BOB、CDs/BOB和TCPP/BOB的2.3、1.8和2.0倍.这项工作为探索用于水净化的有机/无机三元S型光催化剂提供了新的视角.
Solar-powered photocatalysis for treating pharmaceutical wastewater is a promising approach for tackling environmental issues and energy crisis.However,its efficiency is hindered by unsatisfactory light-absorption efficiency,rapid charge recombination,and weak photo-redox potential.Here,an organic/inorganic ternary S-scheme system of carbon quantum dots(CDs)/tetra(4-carboxyphenyl)porphyrin/BiOBr(TCPP/CDs/BOB)was ingeniously built by depositing CDs and TCPP onto BOB microspheres for effective purification of tetracycline hydrochloride(TC)under visible light.The Fermi level difference triggers electron delivery from TCPP to BOB upon hybridization,thereby creating an internal electric field(IEF)at the interface.This impels the effective separation of powerful photo-induced carriers.Moreover,CDs perform as electron reservoirs to further promote S-scheme carrier separation.Thus,more powerful photoelectrons in the CDs and holes in the BOB valence band are reserved for participation in photocatalytic reactions.The optimized TCPP/CDs/BOB-2 heterostructure exhibits an enhanced TC degradation capacity of 83.6%within 40 min and the rate constant of TCPP/CDs/BOB-2 is roughly 2.3,1.8 and 2.0 times that of BOB,CDs/BOB,and TCPP/BOB,respectively.This work provides a new perspective for exploring organic/inorganic ternary S-scheme photocatalysts for water purification.
作者
王春春
戎珂
刘艳萍
杨方
李世杰
Chunchun Wang;Ke Rong;Yanping Liu;Fang Yang;Shijie Li(Key Laboratory of Health Risk Factors for Seafood of Zhejiang Province,National Engineering Research Center for Marine Aquaculture,College of Marine Science and Technology,Zhejiang Ocean University,Zhoushan 316022,China;School of Mechanical and Automotive Engineering,Shanghai University of Engineering Science,Shanghai 201620,China)
基金
supported by the National Natural Science Foundation of China(U1809214)
the Natural Science Foundation of Zhejiang Province(LY20E080014,LTGN23E080001)
the Science and Technology Project of Zhoushan(2022C41011)。
