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Copper oxide and hematite (CuO/α-Fe2O3) composite catalysts were prepared by using goethite as precursor adopted impregnation way and applied to the dielectric barrier discharge (DBD) catalytic decomposition of gaseous chlorobenzene. The CuO/α-Fe2O3 composite was characterised by X-ray diffraction, Brunauer–Emmett–Teller method, scanning electron microscopy and X-ray photoelectron spectrometer technique. The decomposition efficiency and energy yield of gaseous chlorobenzene in DBD catalysis system were studied by a function of gas flow rate, initial concentration and input voltage. The results showed that the CuO/α-Fe2O3 composite catalyst exhibited remarkable performance on chlorobenzene decomposition when the molar ratio was 0.4 and calcination temperature was 450°C. When the chlorobenzene initial concentration was 230 mg m−3, the chlorobenzene decomposition efficiency and mineralisation rate on the DBD catalysis system reached 73.33% and 63.37%, respectively, its decomposition and mineralisation efficiency were enhanced about 20.5% and 16.61%, respectively, compared with the bare DBD system, and it also benefited to significantly reduce the ozone and NO2 by-products. The possible pathway of chlorobenzene decomposition in the DBD catalytic hybrid system was proposed based on the products analysis. [ABSTRACT FROM AUTHOR]

Clarifying the formation mechanism of single-atom sites guides the design of emerging single-atom catalysts (SACs) and facilitates the identification of the active sites at atomic scale. Herein, a molten-salt atomization strategy is developed for synthesizing zinc (Zn) SACs with temperature universality from 400 to 1000/1100 °C and an evolved coordination from Zn-N 2 Cl 2 to Zn-N 4 . The electrochemical tests and in situ attenuated total reflectance-surface-enhanced infrared absorption spectroscopy confirm that the Zn-N 4 atomic sites are active for electrochemical carbon dioxide (CO 2 ) conversion to carbon monoxide (CO). In a strongly acidic medium (0.2 m K 2 SO 4 , pH = 1), the Zn SAC formed at 1000 °C (Zn 1 NC) containing Zn-N 4 sites enables highly selective CO 2 electroreduction to CO, with nearly 100% selectivity toward CO product in a wide current density range of 100-600 mA cm -2 . During a 50 h continuous electrolysis at the industrial current density of 200 mA cm -2 , Zn 1 NC achieves Faradaic efficiencies greater than 95% for CO product. The work presents a temperature-universal formation of single-atom sites, which provides a novel platform for unraveling the active sites in Zn SACs for CO 2 electroreduction and extends the synthesis of SACs with controllable coordination sites., (© 2024 Wiley‐VCH GmbH.)

Copper oxide and hematite (CuO/ α -Fe 2 O 3 ) composite catalysts were prepared by using goethite as precursor adopted impregnation way and applied to the dielectric barrier discharge (DBD) catalytic decomposition of gaseous chlorobenzene. The CuO/ α -Fe 2 O 3 composite was characterised by X-ray diffraction, Brunauer-Emmett-Teller method, scanning electron microscopy and X-ray photoelectron spectrometer technique. The decomposition efficiency and energy yield of gaseous chlorobenzene in DBD catalysis system were studied by a function of gas flow rate, initial concentration and input voltage. The results showed that the CuO/ α -Fe 2 O 3 composite catalyst exhibited remarkable performance on chlorobenzene decomposition when the molar ratio was 0.4 and calcination temperature was 450°C. When the chlorobenzene initial concentration was 230 mg m -3 , the chlorobenzene decomposition efficiency and mineralisation rate on the DBD catalysis system reached 73.33% and 63.37%, respectively, its decomposition and mineralisation efficiency were enhanced about 20.5% and 16.61%, respectively, compared with the bare DBD system, and it also benefited to significantly reduce the ozone and NO 2 by-products. The possible pathway of chlorobenzene decomposition in the DBD catalytic hybrid system was proposed based on the products analysis.