Bismuth-based materials(e.g., metallic, oxides and subcarbonate) are emerged as promising electrocatalysts for converting CO_(2) to formate. However, Bio-based electrocatalysts possess high overpotentials, while bismu...Bismuth-based materials(e.g., metallic, oxides and subcarbonate) are emerged as promising electrocatalysts for converting CO_(2) to formate. However, Bio-based electrocatalysts possess high overpotentials, while bismuth oxides and subcarbonate encounter stability issues. This work is designated to exemplify that the operando synthesis can be an effective means to enhance the stability of electrocatalysts under operando CO_(2)RR conditions. A synthetic approach is developed to electrochemically convert Bi^(O)Cl into Cl-containing subcarbonate(Bi_(2)O_(2)(CO_(3))_(x)Cl_(y)) under operando CO_(2)RR conditions. The systematic operando spectroscopic studies depict that BiOCl is converted to Bi_(2)O_(2)(CO_(3))_(x)Cl_(y) via a cathodic potential-promoted anion-exchange process. The operando synthesizedBi_(2)O_(2)(CO_(3))_(x)Cl_(y) can tolerate-1.0 V versus RHE, while for the wet-chemistry synthesized pure Bi_(2)O_(2)CO_(3),the formation of metallic Bio occurs at-0.6 V versus RHE. At-0.8 V versus RHE, Bi_(2)O_(2)(CO_(3))_(x)Cl_(y) can readily attain a FEHCOO-of 97.9%,much higher than that of the pure Bi_(2)O_(2)CO_(3)(81.3%). DFT calculations indicate that differing from the pure Bi_(2)O_(2)CO_(3)-catalyzed CO_(2)RR, where formate is formed via a *OCHO intermediate step that requires a high energy input energy of 2.69 eV to proceed, the formation of H COO-over Bi_(2)O_(2)(CO_(3))_(x)Cl_(y) has proceeded via a *COOH intermediate step that only requires low energy input of 2.56 eV.展开更多
Waste pickling liquors （WPLs） containing high concentrations of iron and acid are hazardous waste products from the steel pickling processes. A novel combined coprecipitation-oxidation method for iron recovery by Fe...Waste pickling liquors （WPLs） containing high concentrations of iron and acid are hazardous waste products from the steel pickling processes. A novel combined coprecipitation-oxidation method for iron recovery by Fe304 nanoparhcle＇ production from the WPLs was developed in this study. 2＋All oxidation-reduction potential monitoring method was developed for real-time control of the Fe2＋/Fe3＋ molar ratio. The key coprecipitation-oxidation parameters were determined using the orthogonal experimental design method. The use of promoters greatly improved the Fe3O4 nanoparticle crystallinity, size, magnetization, and dispersion. X-ray diffraction patterns showed that the produced Fe3O4. nanoparticles were single phase. The Fe3O4 nan oparticles were approximately spherical and slightly aggtomerated. Vibrating sample magnetometry showed that the Fe3O4 nanopahicles produced from the WPLs had good magnetic properties, with a saturation magnetization of 80.206 emu. g-1 and a remanence of 10.500 emu. g-1. The results show that this novel coprecipitation-oxidation method has great potential for recycling iron in WPLs.展开更多
Edible bird＇s nest （EBN） is derived from the saliva of certain types of swiflets. It is consumed in many parts of the world for its nutritional and medicinal values. Although many claims have been made on the thera...Edible bird＇s nest （EBN） is derived from the saliva of certain types of swiflets. It is consumed in many parts of the world for its nutritional and medicinal values. Although many claims have been made on the therapeutic and health- promoting effects of EBN, scientific documentations regarding these effects are very limited in published literature. It is not until recently that the biological effects of EBN are being investigated and evidence-based studies are being conducted. Several studies have found that EBN may enhance cell proliferation and differentiation and various beneficial effects have been reported in vitro as well as in vivo. While these studies point towards the potential use of EBN in the treatment or even prevention of several diseases, the mechanisms of action of EBN remain largely unknown and more explorations are needed. This review is one of the very few scientific reviews onEBN which focuses on recent evidence-based discoveries.展开更多
基金financially supported by Australian Research Council Discovery Project(DP200100965)。
文摘Bismuth-based materials(e.g., metallic, oxides and subcarbonate) are emerged as promising electrocatalysts for converting CO_(2) to formate. However, Bio-based electrocatalysts possess high overpotentials, while bismuth oxides and subcarbonate encounter stability issues. This work is designated to exemplify that the operando synthesis can be an effective means to enhance the stability of electrocatalysts under operando CO_(2)RR conditions. A synthetic approach is developed to electrochemically convert Bi^(O)Cl into Cl-containing subcarbonate(Bi_(2)O_(2)(CO_(3))_(x)Cl_(y)) under operando CO_(2)RR conditions. The systematic operando spectroscopic studies depict that BiOCl is converted to Bi_(2)O_(2)(CO_(3))_(x)Cl_(y) via a cathodic potential-promoted anion-exchange process. The operando synthesizedBi_(2)O_(2)(CO_(3))_(x)Cl_(y) can tolerate-1.0 V versus RHE, while for the wet-chemistry synthesized pure Bi_(2)O_(2)CO_(3),the formation of metallic Bio occurs at-0.6 V versus RHE. At-0.8 V versus RHE, Bi_(2)O_(2)(CO_(3))_(x)Cl_(y) can readily attain a FEHCOO-of 97.9%,much higher than that of the pure Bi_(2)O_(2)CO_(3)(81.3%). DFT calculations indicate that differing from the pure Bi_(2)O_(2)CO_(3)-catalyzed CO_(2)RR, where formate is formed via a *OCHO intermediate step that requires a high energy input energy of 2.69 eV to proceed, the formation of H COO-over Bi_(2)O_(2)(CO_(3))_(x)Cl_(y) has proceeded via a *COOH intermediate step that only requires low energy input of 2.56 eV.
文摘Waste pickling liquors （WPLs） containing high concentrations of iron and acid are hazardous waste products from the steel pickling processes. A novel combined coprecipitation-oxidation method for iron recovery by Fe304 nanoparhcle＇ production from the WPLs was developed in this study. 2＋All oxidation-reduction potential monitoring method was developed for real-time control of the Fe2＋/Fe3＋ molar ratio. The key coprecipitation-oxidation parameters were determined using the orthogonal experimental design method. The use of promoters greatly improved the Fe3O4 nanoparticle crystallinity, size, magnetization, and dispersion. X-ray diffraction patterns showed that the produced Fe3O4. nanoparticles were single phase. The Fe3O4 nan oparticles were approximately spherical and slightly aggtomerated. Vibrating sample magnetometry showed that the Fe3O4 nanopahicles produced from the WPLs had good magnetic properties, with a saturation magnetization of 80.206 emu. g-1 and a remanence of 10.500 emu. g-1. The results show that this novel coprecipitation-oxidation method has great potential for recycling iron in WPLs.
文摘Edible bird＇s nest （EBN） is derived from the saliva of certain types of swiflets. It is consumed in many parts of the world for its nutritional and medicinal values. Although many claims have been made on the therapeutic and health- promoting effects of EBN, scientific documentations regarding these effects are very limited in published literature. It is not until recently that the biological effects of EBN are being investigated and evidence-based studies are being conducted. Several studies have found that EBN may enhance cell proliferation and differentiation and various beneficial effects have been reported in vitro as well as in vivo. While these studies point towards the potential use of EBN in the treatment or even prevention of several diseases, the mechanisms of action of EBN remain largely unknown and more explorations are needed. This review is one of the very few scientific reviews onEBN which focuses on recent evidence-based discoveries.
