Facile low-temperature supercritical carbonization method to prepare high-loading nickel single atom catalysts for efficient photodegradation of tetracycline  

作　　者：Han Qiao Lirong Zheng Shiwen Hu Gang Tang Hongri Suo Chongxuan Liu 

机构地区：[1]School of Environment,Harbin Institute of Technology,Harbin 150090,China [2]State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control,School of Environmental Science and Engineering,Southern University of Science and Technology,Shenzhen 518055,China [3]Beijing Synchrotron Radiation Facility(BSRF),Institute of High Energy Physics,Chinese Academy of Sciences,Beijing 100049,China

出　　处：《Journal of Environmental Sciences》2024年第4期373-384,共12页环境科学学报（英文版）

基　　金：supported by the National Key Research and Development Program(No.2019YFC1803903);the Program for Guangdong Introducing Innovative and Entrepreneurial Teams(No.2017ZT07Z479);China Postdoctoral Science Foundation(No.2021M701561);the National Natural Science Foundation of China(No.42007318)。

摘　　要：Environmental photocatalysis is a promising technology for treating antibiotics in wastewater.In this study,a supercritical carbonization method was developed to synthesize a single-atom photocatalyst with a high loading of Ni(above 5 wt.%)anchored on a carbonnitrogen-silicate substrate for the efficient photodegradation of a ubiquitous environmental contaminant of tetracycline(TC).The photocatalyst was prepared from an easily obtained metal-biopolymer-inorganic supramolecular hydrogel,followed by supercritical drying and carbonization treatment.The low-temperature(300℃)supercritical ethanol treatment prevents the excessive structural degradation of hydrogel and greatly reduces the metal clustering and aggregation,which contributed to the high Ni loading.Atomic characterizations confirmed that Ni was present at isolated sites and stabilized by Ni-N and Ni-O bonds in a Ni-(N/O)_(6)-C/SiC configuration.A 5%Ni-C-Si catalyst,which performed the best among the studied catalysts,exhibited a wide visible light response with a narrow bandgap of 1.45 eV that could efficiently and repeatedly catalyze the oxidation of TC with a conversion rate of almost 100% within 40 min.The reactive species trapping experiments and electron spin resonance(ESR)tests demonstrated that the h+,and·O_(2)-were mainly responsible for TC degradation.The TC degradation mechanism and possible reaction pathways were provided also.Overall,this study proposed a novel strategy to synthesize a high metal loading singleatom photocatalyst that can efficiently remove TC with high concentrations,and this strategy might be extended for synthesis of other carbon-based single-atom catalysts with valuable properties.

关 键 词：Carbon-based single-atom catalyst NICKEL Photocatalytic degradation TETRACYCLINE Visible light 

分 类 号：X703[环境科学与工程—环境工程] TQ426[化学工程]