Facet- and defect-dependent activity of perovskites in catalytic evolution of sulfate radicals

2021

Environ. Sci. Technol.

129

It is still a challenge to synthesize highly efficient and stable catalysts for the Fenton-like reaction. In this study, we constructed an integrated catalyst with highly dispersed iron-based dual active sites, in which Fe2N and single-atom Fe (SA-Fe) were embedded into nitrogen- and oxygen-co-doped graphitic carbon (Fe-N-O-GC-350). Extended X-ray absorption fine structure (EXAFS) confirmed the coordination structure of iron, and line combination fitting (LCF) demonstrated the coexistence of Fe2N and SA-Fe with percentages of 75 and 25%, respectively. Iron-based dual active sites endowed Fe-N-O-GC-350 with superior catalytic activity to activate peroxymonosulfate (PMS) as evidenced by the fast degradation rate of sulfamethoxazole (SMX) (0.24 min–1) in the presence of 0.4 mM PMS and 0.1 g/L Fe-N-O-GC-350. Unlike the reported singlet oxygen and high-valent iron oxo-mediated degradation induced by the SA-Fe catalyst, both surface-bound reactive species and singlet oxygen contributed to SMX degradation, while surface-bound reactive species dominated. Density functional theory (DFT) simulation indicated that Fe2N and SA-Fe enhanced the adsorption of PMS, which played a key role in PMS activation. The Fe-N-O-GC-350/PMS system had resistance to the interference of common inorganic anions and high oxidation capacity to recalcitrant organic contaminants. This study elucidated the important role of Fe2N in PMS activation and provide a clue to design rationally catalysts with iron-based dual active sites to activate PMS for the degradation of emerging organic pollutants.

Section: Resultscontrasting

confidence: 47%

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Iron-Based Dual Active Site-Mediated Peroxymonosulfate Activation for the Degradation of Emerging Organic Pollutants

2021

Environ. Sci. Technol.

129

“…In addition, the characteristic DMPO‐OH and DMPO‐SO 4 signals were consistent with previous reports. [ 47–50 ] Such characterization fully verified the existence of SO 4 ·− and OH· in this catalytic system.…”

Section: Resultsmentioning

confidence: 56%

“…www.advmatinterfaces.de DMPO-SO 4 signals were consistent with previous reports. [47][48][49][50] Such characterization fully verified the existence of SO 4…”

Section: Identification Of Active Speciesmentioning

confidence: 56%

Biotemplated Shell Micromotors for Efficient Degradation of Antibiotics via Enhanced Peroxymonosulfate Activation

Hong

2022

Adv Materials Inter

Self‐propelled magnetic MnO2@pollen micromotors have been developed as active heterogeneous catalysts of peroxymonosulfate (PMS) activation for efficient degradation of antibiotics. The MnO2 nanosheets (NSs) and Fe3O4 nanoparticles (NPs) are constructed on hollow pollens with small openings, endowing the natural materials with multifunctional properties. MnO2 NSs can decompose H2O2 to provide propulsion for micromotor movement, and also cooperate with Fe3O4 NPs to activate PMS to produce active free radicals SO4·−. Together with the OH· generated by Fe3O4 NPs and H2O2, the prepared micromotor catalyst can realize the degradation of tetracycline (TC) within several minutes. The self‐propulsion and abundant bubble formation cause effective fluid mixing and intensification of mass transfer, making up the low diffusivity defect of traditional heterogeneous catalysts. Moreover, the magnetic properties lay a foundation for the long‐range magnetic control and reutilization of heterogeneous catalysts, avoiding wastage and secondary contamination. The proposed self‐propelled pollen micromotors provide a highly efficient, economic, and environmentally friendly platform for the degradation of antibiotics.

Perovskite Oxide Catalysts for Advanced Oxidation Reactions

Chen

Shao

et al. 2021

Adv Funct Materials

Self Cite

133

Meeting the escalating demand for clean water resources is one of the key challenges to ensure a sustainable future. Catalysis plays an important role to advance the chemical reactions required for wastewater efficient remediation. How to exploit high-performance catalysts to boost the pivotal reaction kinetics always attracts researchers' enthusiasm. Perovskite oxides as a novel class of functional materials can be tuned to confer compositional flexibilities and provide rich and unique structural properties. As the rising-star material, it has been widely probed for electrocatalysis, photocatalysis, and membrane-catalysis for energy conversion, but received less attention in water treatment. In this review, the advances of perovskite oxides for advanced oxidation processes (AOPs) in water remediation are comprehensively elaborated. A fundamental understanding of the crystal structures and properties of perovskite oxides as well as the basic principles of AOPs is firstly provided. Then, emphasis is placed on how to tune the perovskite oxides to suit various AOPs. The strategies to design novel perovskite oxides to enhance the catalytic activities in AOPs have been highlighted. It is expected that after reading this review, readers will have a clearer vision of the background, the state of the art development, and general guidelines for future directions regarding research in this area.