The reduction of carbon emissions in the steel industry is a significant challenge,and utilizing CO_(2) from carbon intensive steel industry off-gases for methanol production is a promising strategy for decarbonizatio...The reduction of carbon emissions in the steel industry is a significant challenge,and utilizing CO_(2) from carbon intensive steel industry off-gases for methanol production is a promising strategy for decarbonization.However,steelwork off-gases typically contain various impurities,including H_(2)S,which can deactivate commercial methanol synthesis catalysts,Cu/ZnO/Al_(2)O_(3)(CZA).Reverse water-gas shift(RWGS)reaction is the predominant side reaction in CO_(2) hydrogenation to methanol which can occur at ambient pressure,enabling the decouple of RWGS from methanol production at high pressure.Then,a series of activated CZA catalysts has been in-situ pretreated in 400 ppm H_(2)S/Ar at 250℃and tested for both RWGS reaction at ambient pressure and CO_(2) hydrogenation to methanol at high pressure.An innovative decoupling strategy was employed to isolate the RWGS reaction from the methanol synthesis process,enabling the investigation of the evolution of active site structures and the poisoning mechanism through elemental analysis,X-ray Diffraction,X-ray Photoelectron Spectroscopy,Fourier Transform Infrared Spectroscopy,Temperature Programmed Reduction and CO_(2) Temperature Programmed Desorption.The results indicate that there are different dynamic migration behaviors of ZnO_(x) in the two reaction systems,leading to different poisoning mechanisms.These interesting findings are beneficial to develop sulfur resistant and durable highly efficient catalysts for CO_(2) hydrogenation to methanol,promoting the carbon emission reduction in steel industry.展开更多
Developing efficient photocatalysts for CO_(2)conversion under full-spectrum irradiation remains a key challenge for solar-to-chemical energy conversion.In this study,a novel S-scheme heterojunction composed of reduct...Developing efficient photocatalysts for CO_(2)conversion under full-spectrum irradiation remains a key challenge for solar-to-chemical energy conversion.In this study,a novel S-scheme heterojunction composed of reduction Cs_(0.32)WO_(3)(CWO)nanosheets with hexagonal structure and oxidation WO_(3)·2H_(2)O(WO)nanorods with monoclinic structure photocatalyst was successfully constructed via an ultrasound strategy.Under full-spectrum irradiation for 4 h,the optimized 2D/1D of heterostructure CWO/WO-0.8 exhibited superior photocatalytic performance,achieving CO and CH_(3)OH yields of 29.74 and 63.71μmol·g^(-1),respectively.The enhanced activity is primarily ascribed to the formation of an S-scheme charge transfer pathway,which facilitates efficient separation and directional migration of photogenerated charge carriers through the internal electric field at the CWO/WO interface.This process facilitates the electron enrichment on the CWO surface and significantly enhances its CO_(2)reduction ability.Besides,the results of various characterizations show that CWO/WO-0.8 possesses enhanced optical response capability.The results of density functional theory calculations and CO_(2)-temperature programmed desorption analysis confirmed that the CWO/WO heterojunction exhibits stronger CO_(2)adsorption and activation abilities compared to the pristine CWO and WO.The reaction pathway for CH_(3)OH production was elucidated by in-situ diffused reflectance Fourier transformed infrared tests.This work provides new insights into the rational design of S-scheme photocatalysts for efficient and selective CO_(2)conversion.展开更多
Both whisker and nanometer MgSO4·5Mg(OH)2·3H2O(MOS) were prepared by hydrothermal method at 140℃for different times, using NaOH and MgSO4·7H2O as raw materials. The MgSO4·5Mg(OH)2·3H2O part i...Both whisker and nanometer MgSO4·5Mg(OH)2·3H2O(MOS) were prepared by hydrothermal method at 140℃for different times, using NaOH and MgSO4·7H2O as raw materials. The MgSO4·5Mg(OH)2·3H2O part icles were characterized by powder X ray diffraction(XRD),thermal analysis(TGA DSC), infrared spectroscopy(FT IR),transmission electron microscopy(SEM) and scanning electron microscopy(TEM). The size distribution in whisker like and nanocrystalline materials arein the range of 10～50μm and 10～20nm respectively. The whisker MOS is metastable phase in MgSO4 NaOH H2O system at 140℃,whereas nanometer MOS is stable phase.展开更多
PhCH2)3Sn·(O2CC5H4N)·(H2O)]n was synthesized by the reaction of 4-pyridine car-boxylic acid with the tribenzyltin o xide and was characterized by IR,1 H NMR and MS.Its crystal structure was determined by X-r...PhCH2)3Sn·(O2CC5H4N)·(H2O)]n was synthesized by the reaction of 4-pyridine car-boxylic acid with the tribenzyltin o xide and was characterized by IR,1 H NMR and MS.Its crystal structure was determined by X-ray single crystal diffraction.The crystal belongs to monoclinic.The space group P21 /c with unit cell parameters a=1.2241(8)nm,b=0.9660(6)nm,c=2.3708(15)nm,β=102.722(12)°,V=2.734(3)nm3,Z =4,Dc=1.298g·cm-3 .In crystal,the tin atom rendered five-coordinate in a trigo nal bipyramidal structure which is b ridged by 4-pyridine carboxy-late into one-dimensional chain polymers.展开更多
基金supported by the National Natural Science Foundation of China(Nos.22276060 and 21976059)Guangdong Basic and Applied Basic Research Foundation(No.2024A1515012636)China Scholarship Council Scholarship(No.201906155006)。
文摘The reduction of carbon emissions in the steel industry is a significant challenge,and utilizing CO_(2) from carbon intensive steel industry off-gases for methanol production is a promising strategy for decarbonization.However,steelwork off-gases typically contain various impurities,including H_(2)S,which can deactivate commercial methanol synthesis catalysts,Cu/ZnO/Al_(2)O_(3)(CZA).Reverse water-gas shift(RWGS)reaction is the predominant side reaction in CO_(2) hydrogenation to methanol which can occur at ambient pressure,enabling the decouple of RWGS from methanol production at high pressure.Then,a series of activated CZA catalysts has been in-situ pretreated in 400 ppm H_(2)S/Ar at 250℃and tested for both RWGS reaction at ambient pressure and CO_(2) hydrogenation to methanol at high pressure.An innovative decoupling strategy was employed to isolate the RWGS reaction from the methanol synthesis process,enabling the investigation of the evolution of active site structures and the poisoning mechanism through elemental analysis,X-ray Diffraction,X-ray Photoelectron Spectroscopy,Fourier Transform Infrared Spectroscopy,Temperature Programmed Reduction and CO_(2) Temperature Programmed Desorption.The results indicate that there are different dynamic migration behaviors of ZnO_(x) in the two reaction systems,leading to different poisoning mechanisms.These interesting findings are beneficial to develop sulfur resistant and durable highly efficient catalysts for CO_(2) hydrogenation to methanol,promoting the carbon emission reduction in steel industry.
文摘Developing efficient photocatalysts for CO_(2)conversion under full-spectrum irradiation remains a key challenge for solar-to-chemical energy conversion.In this study,a novel S-scheme heterojunction composed of reduction Cs_(0.32)WO_(3)(CWO)nanosheets with hexagonal structure and oxidation WO_(3)·2H_(2)O(WO)nanorods with monoclinic structure photocatalyst was successfully constructed via an ultrasound strategy.Under full-spectrum irradiation for 4 h,the optimized 2D/1D of heterostructure CWO/WO-0.8 exhibited superior photocatalytic performance,achieving CO and CH_(3)OH yields of 29.74 and 63.71μmol·g^(-1),respectively.The enhanced activity is primarily ascribed to the formation of an S-scheme charge transfer pathway,which facilitates efficient separation and directional migration of photogenerated charge carriers through the internal electric field at the CWO/WO interface.This process facilitates the electron enrichment on the CWO surface and significantly enhances its CO_(2)reduction ability.Besides,the results of various characterizations show that CWO/WO-0.8 possesses enhanced optical response capability.The results of density functional theory calculations and CO_(2)-temperature programmed desorption analysis confirmed that the CWO/WO heterojunction exhibits stronger CO_(2)adsorption and activation abilities compared to the pristine CWO and WO.The reaction pathway for CH_(3)OH production was elucidated by in-situ diffused reflectance Fourier transformed infrared tests.This work provides new insights into the rational design of S-scheme photocatalysts for efficient and selective CO_(2)conversion.
文摘Both whisker and nanometer MgSO4·5Mg(OH)2·3H2O(MOS) were prepared by hydrothermal method at 140℃for different times, using NaOH and MgSO4·7H2O as raw materials. The MgSO4·5Mg(OH)2·3H2O part icles were characterized by powder X ray diffraction(XRD),thermal analysis(TGA DSC), infrared spectroscopy(FT IR),transmission electron microscopy(SEM) and scanning electron microscopy(TEM). The size distribution in whisker like and nanocrystalline materials arein the range of 10～50μm and 10～20nm respectively. The whisker MOS is metastable phase in MgSO4 NaOH H2O system at 140℃,whereas nanometer MOS is stable phase.
文摘PhCH2)3Sn·(O2CC5H4N)·(H2O)]n was synthesized by the reaction of 4-pyridine car-boxylic acid with the tribenzyltin o xide and was characterized by IR,1 H NMR and MS.Its crystal structure was determined by X-ray single crystal diffraction.The crystal belongs to monoclinic.The space group P21 /c with unit cell parameters a=1.2241(8)nm,b=0.9660(6)nm,c=2.3708(15)nm,β=102.722(12)°,V=2.734(3)nm3,Z =4,Dc=1.298g·cm-3 .In crystal,the tin atom rendered five-coordinate in a trigo nal bipyramidal structure which is b ridged by 4-pyridine carboxy-late into one-dimensional chain polymers.
