采用共沉淀法制备了AgBr/Ag_(2)CO_(3)复合催化剂。研究表明,AgBr/Ag_(2)CO_(3)复合催化剂的光催化性能比单一相的AgBr或Ag_(2)CO_(3)显著提高,0.10 g AgBr/Ag_(2)CO_(3)样品光照降解200 mL 10 mg/L的亚甲基蓝溶液20 min后,降解率高达99...采用共沉淀法制备了AgBr/Ag_(2)CO_(3)复合催化剂。研究表明,AgBr/Ag_(2)CO_(3)复合催化剂的光催化性能比单一相的AgBr或Ag_(2)CO_(3)显著提高,0.10 g AgBr/Ag_(2)CO_(3)样品光照降解200 mL 10 mg/L的亚甲基蓝溶液20 min后,降解率高达99.97%,是AgBr的2.5倍,是Ag_(2)CO_(3)的4.77倍,且AgBr/Ag_(2)CO_(3)对亚甲基蓝的降解过程符合一级动力学模型。展开更多
Utilizing solar energy to achieve artificial photosynthesis of chemical fuel is prevalent in tackling excessive CO_(2)emission and fossil fuel depletion.Grievous charge recombination and weak redox capability aggravat...Utilizing solar energy to achieve artificial photosynthesis of chemical fuel is prevalent in tackling excessive CO_(2)emission and fossil fuel depletion.Grievous charge recombination and weak redox capability aggravate the CO_(2)photoreduction performance.Engineering tailored morphology and constructing matched heterostructure are two significant schemes to ameliorate the CO_(2)photoconversion efficiency of g-C_(3)N_(4)-based composite.Herein,a novel S-scheme ultrathin porous g-C_(3)N_(4)(UPCN)/Ag_(2)MoO_(4)(AMO)composite was designed by in-situ growing tetragonalα-AMO nanoparticles(NPs)(5-30 nm)on UPCN nanosheets(NSs).The S-scheme charge transfer route endows UPCN/AMO with fast charge separation and strong redox capability,demonstrated by X-ray photoelectron spectroscopy(XPS),photoelectrochemical tests,steady-state and time-resolved photoluminescence(PL)spectra,and DFT calculations.The UPCN/AMO composite exhibits elevated CO_(2)photoreduction performance with CO and CH_(4)yield rates of 6.98 and 0.38μmol g^(-1)h^(-1),which are 3.5 and 2.9 folds higher than that of pristine UPCN,respectively.Finally,the CO_(2)photoreduction intermediates are analyzed,and the CO_(2)photoreduction mechanism is discussed.This work provides a reference for various g-C_(3)N_(4)-based composites applied in artificial photosynthesis.展开更多
Photothermal carbon dioxide hydrogenation represents a promising route to reduce the emission of greenhouse gas CO_(2)and produce value-added chemicals,but the selectivity and stability of photothermal catalysts need ...Photothermal carbon dioxide hydrogenation represents a promising route to reduce the emission of greenhouse gas CO_(2)and produce value-added chemicals,but the selectivity and stability of photothermal catalysts need to be improved.Herein,we report the rational fabrication of well-defined Ag_(24)Au cluster decorated highly ordered nanorod-like mesoporous Co_(3)O_(4)(Ag_(24)Au/mesoCo_(3)O_(4))for highly efficient and selective CO_(2)hydrogenation.The orderly assembled meso-Co_(3)O_(4)nanorods were prepared via a nanocasting method,offering large surface area and abundant active sites for CO_(2)adsorption and conversion.Moreover,the catalytic activity and selectivity were further improved by molecule-like Ag_(24)Au cluster decoration and reaction temperature optimization.The Ag_(24)Au/meso-Co_(3)O_(4)composite catalyst exhibited an ultrahigh CH_(4)yield rate of 204 mmol·g^(−1)·h^(−1)and a greatly improved CH_(4)selectivity of 82%for CO_(2)hydrogenation,significantly higher than those of pristine meso-Co_(3)O_(4)catalyst.The mechanism of the photothermal catalytic performance improvement was verified by CO_(2)temperature-programmed desorption and time-resolved transient photoluminescence,revealing that CO_(2)molecules underwent a vigorous adsorption and rapid activation process over Ag_(24)Au/meso-Co_(3)O_(4).The hot electrons created by the localized surface plasmon resonance effect of Ag_(24)Au clusters facilitated the charge transfer for subsequent multi-electron CO_(2)hydrogeneration processes,resulting in a significant increase in the productivity and selectivity for CO_(2)-to-CH_(4)conversion.This work suggests that the rational coupling of well-defined metal atom clusters and ordered transition metal compound nanostructures could open a new avenue towards photoinduced green chemistry processes for efficient CO_(2)recycling and reutilization.展开更多
Photocatalytic degradation was considered as a best strategy for the removal of antibiotic drug pollutants from wastewater.The photocatalyst of ABC (Ag_(2)CO_(3)/BiOBr/CdS) composite synthesized by hydrothermal and pr...Photocatalytic degradation was considered as a best strategy for the removal of antibiotic drug pollutants from wastewater.The photocatalyst of ABC (Ag_(2)CO_(3)/BiOBr/CdS) composite synthesized by hydrothermal and precipitation method.The ABC composite used to investigate the degradation activity of tetracycline (TC) under visible light irradiation.The physicochemical characterization methods (e.g.scanning electron microscopy (SEM),transmission electron microscopy (TEM),high resolution-transmission electron microscopy (HR-TEM),ultraviolet visible spectroscopy (UV),photoluminescence (PL) and time resolved photoluminescence (TRPL) clearly indicate that the composite has been construct successfully that enhances the widened visible light absorption,induces charge transfer and separation efficiency of electron–hole pairs.The photocatalytic activity of all samples was examined through photodegradation of tetracycline in aqueous medium.The photocatalytic degradation rate of ABC catalyst could eliminate 98.79% of TC in 70 min,which is about 1.5 times that of Ag_(2)CO_(3),1.28 times that of BiOBr and 1.1 times that of BC catalyst,respectively.The role of operation parameters like,TC concentration,catalyst dosage and initial pH on TC degradation activity were studied.Quenching experiment was demonstrated that·OH and O_(2)·-were played a key role during the photocatalysis process that was evidently proved in electron paramagnetic resonance (EPR) experiment.In addition,the catalyst showed good activity perceived in reusability and stability test due to the synergistic effect between its components.The mechanism of degradation of TC in ABC composite was proposed based on the detailed analysis.The current study will give an efficient and recyclable photocatalyst for antibiotic aqueous pollutant removal.展开更多
文摘采用共沉淀法制备了AgBr/Ag_(2)CO_(3)复合催化剂。研究表明,AgBr/Ag_(2)CO_(3)复合催化剂的光催化性能比单一相的AgBr或Ag_(2)CO_(3)显著提高,0.10 g AgBr/Ag_(2)CO_(3)样品光照降解200 mL 10 mg/L的亚甲基蓝溶液20 min后,降解率高达99.97%,是AgBr的2.5倍,是Ag_(2)CO_(3)的4.77倍,且AgBr/Ag_(2)CO_(3)对亚甲基蓝的降解过程符合一级动力学模型。
基金supported by the National Natural Science Foundation of China(51572103 and 51973078)the Distinguished Young Scholar of Anhui Province(1808085J14)+1 种基金the Major Projects of Education Department of Anhui Province(KJ2020ZD005)the Key Foundation of Educational Commission of Anhui Province(KJ2019A0595)。
文摘Utilizing solar energy to achieve artificial photosynthesis of chemical fuel is prevalent in tackling excessive CO_(2)emission and fossil fuel depletion.Grievous charge recombination and weak redox capability aggravate the CO_(2)photoreduction performance.Engineering tailored morphology and constructing matched heterostructure are two significant schemes to ameliorate the CO_(2)photoconversion efficiency of g-C_(3)N_(4)-based composite.Herein,a novel S-scheme ultrathin porous g-C_(3)N_(4)(UPCN)/Ag_(2)MoO_(4)(AMO)composite was designed by in-situ growing tetragonalα-AMO nanoparticles(NPs)(5-30 nm)on UPCN nanosheets(NSs).The S-scheme charge transfer route endows UPCN/AMO with fast charge separation and strong redox capability,demonstrated by X-ray photoelectron spectroscopy(XPS),photoelectrochemical tests,steady-state and time-resolved photoluminescence(PL)spectra,and DFT calculations.The UPCN/AMO composite exhibits elevated CO_(2)photoreduction performance with CO and CH_(4)yield rates of 6.98 and 0.38μmol g^(-1)h^(-1),which are 3.5 and 2.9 folds higher than that of pristine UPCN,respectively.Finally,the CO_(2)photoreduction intermediates are analyzed,and the CO_(2)photoreduction mechanism is discussed.This work provides a reference for various g-C_(3)N_(4)-based composites applied in artificial photosynthesis.
基金supports from the National Key Research&Development Program of China(No.2017YFA0208200)the National Natural Science Foundation of China(Nos.22022505 and 21872069)+1 种基金the Fundamental Research Funds for the Central Universities(No.0205-14380266)the 2021 Suzhou Gusu Leading Talents of Science and Technology Innovation and Entrepreneurship in Wujiang District.
文摘Photothermal carbon dioxide hydrogenation represents a promising route to reduce the emission of greenhouse gas CO_(2)and produce value-added chemicals,but the selectivity and stability of photothermal catalysts need to be improved.Herein,we report the rational fabrication of well-defined Ag_(24)Au cluster decorated highly ordered nanorod-like mesoporous Co_(3)O_(4)(Ag_(24)Au/mesoCo_(3)O_(4))for highly efficient and selective CO_(2)hydrogenation.The orderly assembled meso-Co_(3)O_(4)nanorods were prepared via a nanocasting method,offering large surface area and abundant active sites for CO_(2)adsorption and conversion.Moreover,the catalytic activity and selectivity were further improved by molecule-like Ag_(24)Au cluster decoration and reaction temperature optimization.The Ag_(24)Au/meso-Co_(3)O_(4)composite catalyst exhibited an ultrahigh CH_(4)yield rate of 204 mmol·g^(−1)·h^(−1)and a greatly improved CH_(4)selectivity of 82%for CO_(2)hydrogenation,significantly higher than those of pristine meso-Co_(3)O_(4)catalyst.The mechanism of the photothermal catalytic performance improvement was verified by CO_(2)temperature-programmed desorption and time-resolved transient photoluminescence,revealing that CO_(2)molecules underwent a vigorous adsorption and rapid activation process over Ag_(24)Au/meso-Co_(3)O_(4).The hot electrons created by the localized surface plasmon resonance effect of Ag_(24)Au clusters facilitated the charge transfer for subsequent multi-electron CO_(2)hydrogeneration processes,resulting in a significant increase in the productivity and selectivity for CO_(2)-to-CH_(4)conversion.This work suggests that the rational coupling of well-defined metal atom clusters and ordered transition metal compound nanostructures could open a new avenue towards photoinduced green chemistry processes for efficient CO_(2)recycling and reutilization.
基金Supporting Project number (No. RSP-2021/6), King Saud University, Riyadh, Saudi Arabia。
文摘Photocatalytic degradation was considered as a best strategy for the removal of antibiotic drug pollutants from wastewater.The photocatalyst of ABC (Ag_(2)CO_(3)/BiOBr/CdS) composite synthesized by hydrothermal and precipitation method.The ABC composite used to investigate the degradation activity of tetracycline (TC) under visible light irradiation.The physicochemical characterization methods (e.g.scanning electron microscopy (SEM),transmission electron microscopy (TEM),high resolution-transmission electron microscopy (HR-TEM),ultraviolet visible spectroscopy (UV),photoluminescence (PL) and time resolved photoluminescence (TRPL) clearly indicate that the composite has been construct successfully that enhances the widened visible light absorption,induces charge transfer and separation efficiency of electron–hole pairs.The photocatalytic activity of all samples was examined through photodegradation of tetracycline in aqueous medium.The photocatalytic degradation rate of ABC catalyst could eliminate 98.79% of TC in 70 min,which is about 1.5 times that of Ag_(2)CO_(3),1.28 times that of BiOBr and 1.1 times that of BC catalyst,respectively.The role of operation parameters like,TC concentration,catalyst dosage and initial pH on TC degradation activity were studied.Quenching experiment was demonstrated that·OH and O_(2)·-were played a key role during the photocatalysis process that was evidently proved in electron paramagnetic resonance (EPR) experiment.In addition,the catalyst showed good activity perceived in reusability and stability test due to the synergistic effect between its components.The mechanism of degradation of TC in ABC composite was proposed based on the detailed analysis.The current study will give an efficient and recyclable photocatalyst for antibiotic aqueous pollutant removal.
