Magnesium-based solid-state hydrogen storage materials(Mg-HSMs)exhibit significant potential for the global energy transition due to their large hydrogen capacity and energy density.However,their high operating temper...Magnesium-based solid-state hydrogen storage materials(Mg-HSMs)exhibit significant potential for the global energy transition due to their large hydrogen capacity and energy density.However,their high operating temperatures,low operating efficiencies,and short service life have severely hindered largescale applications.To address the above challenges,diverse modification strategies have been proposed.Catalytic modification,achieved by introducing catalysts to enable compositional compounding and structural refinement,enhances surface active site density and bulk hydrogen diffusion pathways,reduces hydrogen dissociation energy barriers,weakens Mg–H bonds,and significantly improves kinetic properties.This approach is considered one of the most effective strategies.However,as research advances,the structures,forms,and catalytic mechanisms of catalysts have become increasingly diverse.Despite progress,challenges such as fragmented research outcomes,inconsistent performance metrics,and an incomplete understanding of structure-property relationships remain unresolved.Therefore,this work systematically summarizes recent advances in catalytic modification strategies for Mg-HSMs,emphasizing the role of catalysts in enhancing reaction kinetics and structural stability,the diversity of catalyst types,forms,and the underlying mechanisms governing catalytic efficacy.Based on critical analysis,this work identifies the current key technical bottlenecks and proposes that the design of next-generation catalysts and the future development of Mg-HSMs should be guided by the principles of‘multiphase heterogeneous interfacial composites'and‘synergistic development',aiming to provide theoretical guidance for the optimization and advancement of their performance.展开更多
NiMnO3 perovskite catalysts supported on cordierite modified by CexZr（1-x）O2 coatings were prepared using impregnation and sol-gel methods for catalytic combustion of single/double component VOCs at different concen...NiMnO3 perovskite catalysts supported on cordierite modified by CexZr（1-x）O2 coatings were prepared using impregnation and sol-gel methods for catalytic combustion of single/double component VOCs at different concentrations and GHSV of 15,000 h^（-1）, which were characterized by BET, XRD, SEM, FT-IR, H2-TPR and O2-TPD. After coating modification, the specific surface area of catalysts is improved obviously.Among the catalysts, the Ce（0.75）Zr（0.25）O2 coating modified NiMnO3 catalyst exhibits the best catalytic activity for VOCs combustion with 95.6% conversion at 275 ℃ and has stable activity when catalyst is embalmed at 800 ℃. In addition, the catalyst also presents the excellent water-resistant and conversion stability over time-on-stream condition. The reason is that Ce（0.75）Zr（0.25）O2 coating can promote more lattice distortion and defects and smaller crystal size, which improve oxygen transfer capability and dispersion of active component.展开更多
Commercial spherical activated carbon（SAC） was modified by impregnation to enhance the catalytic properties of SAC in acetylene hydrochlorination through melamine modification. Different modification conditions for ...Commercial spherical activated carbon（SAC） was modified by impregnation to enhance the catalytic properties of SAC in acetylene hydrochlorination through melamine modification. Different modification conditions for SAC with nitrogen were compared by changing the SAC-Melamine ratios. The effect of carbonization temperature on the modification was also investigated. Surface chemistry and adsorption properties of the modified and unmodified SACs were studied by scanning electron microscope（SEM）, X-ray photoelectron spectroscopy（XPS）, elementary analysis, BET, and temperature-programmed desorption（TPD）. Moreover, the catalytic properties of SAC in acetylene hydrochlorination under differently modified conditions were also investigated. Elemental analysis showed that the nitrogen content of the modified SAC was greatly improved. XPS revealed that nitrogen mainly exists in Pyrrole nitrogen and Pyridine nitrogen. TPD showed that desorption of C2H2 was changed by modification. The conversion rate of acetylene was up to 70% under the following reaction conditions： temperature, 150 ℃; C2H2 hourly space velocity（GHSV）, 36 h-1; feed volume ratio V（HCl）/V（C2H2） = 1.15. The catalytic properties of SAC were improved significantly via melamine modification.展开更多
Hydrogen holds the advantages of high energy density,great natural abundance and zero emission,making it suitable for large scale and long term energy storage,while its safe and efficient storage is still challenging....Hydrogen holds the advantages of high energy density,great natural abundance and zero emission,making it suitable for large scale and long term energy storage,while its safe and efficient storage is still challenging.Among various solid state hydrogen storage materials,MgH_(2) is promising for industrial applications due to its high gravimetric and volumetric hydrogen densities and the abundance of Mg on earth.However,the practical application of MgH_(2) has been limited by its stable thermodynamics and slow hydrogen desorption kinetics.Nanocatalysis is considered as a promising approach for improving the hydrogen storage performance of MgH_(2) and bringing it closer to the requirements of commercial applications.It is worth mentioning that the recently emerging two-dimensional material,MXene,has showcased exceptional catalytic abilities in modifying the hydrogen storage properties of MgH_(2).Besides,MXene possesses a high surface area,excellent chemical/physical stability,and negatively charged terminating groups,making it an ideal support for the"nanoconfinement"of MgH_(2) or highly active catalysts.Herein,we endeavor to provide a comprehensive overview of recent investigations on MXene-based catalysts and MXene supports for improving the hydrogen sorption properties of Mg/MgH_(2).The mechanisms of hydrogen sorption involved in Mg-MXene based composites are highlighted with special emphases on thermodynamics,kinetics,and catalytic behaviors.The aim of this work is to provide a comprehensive and objective review of researches on the development of high-performance catalysts/supports to improve hydrogen storage performances of Mg/MgH_(2) and to identify the opportunities and challenges for future applications.展开更多
The Cu-Mn catalysts doped with different amounts of lanthanum（La） for water-gas shift reaction（WGSR） were prepared, and characterized by X-ray diffraction（XRD）, temperature-programmed reduction（TPR）, temperatu...The Cu-Mn catalysts doped with different amounts of lanthanum（La） for water-gas shift reaction（WGSR） were prepared, and characterized by X-ray diffraction（XRD）, temperature-programmed reduction（TPR）, temperature-programmed reduction of oxidized surfaces（s-TPR）, temperature-programmed desorption of CO_2（CO_2-TPD）, infrared spectrum（FT-IR） and X-ray photoelectron spectroscopy（XPS）. Catalytic activities were tested for a water-gas shift reaction. The results showed that the introduction of 0.5 mol.% La could significantly improve the catalyst activity for low-temperature shift reaction compared with the undoped catalyst, which might be from the introduction of La making the Cu and Mn components distribute uniformly and the synergistic effect between Cu and Mn increasing the dispersion of Cu on the surface of the catalyst. The apparent CuO phases besides Cu_（1.5）Mn_（1.5）O_4 were found in the samples with at least 3.0 mol.% La content, and the basic sites increased with the increasing of La contents at a decreased rate. With excessive La doping, La particles would aggregate and cover some active sites, resulting in that Mn could not effectively inhibit the gathering together and growing up of Cu crystalline grain, and decreased the dispersion of Cu on the surface, which resulted in the poor activity of the catalyst for WGSR.展开更多
In the present work,highly effective Ni-MnO binary nanocomposite catalysts were designed and synthesized using a one-pot method from Ni-Mn based bi-metal organic frameworks(MOFs).These nanocomposites were introduced i...In the present work,highly effective Ni-MnO binary nanocomposite catalysts were designed and synthesized using a one-pot method from Ni-Mn based bi-metal organic frameworks(MOFs).These nanocomposites were introduced into MgH_(2) through ball milling as catalysts to enhance the hydrogen storage properties of MgH_(2).Through varying the Ni/Mn ratio in the bimetal MOFs,it is found that the Ni_(1)Mn_(1)-MOF derived catalyst showed the best promotion effect on MgH_(2).The MgH_(2)-10 wt.%Ni_(1)Mn_(1)-MOF derivative demonstrated favorable overall performance with the low desorption peak temperature(218.2℃)with a saturated hydrogen capacity of 6.42 wt.%and rapid hydrogen release/uptake kinetics.It can still reabsorb about 1.15 wt.%H_(2) within 30 min at a temperature as low as 50℃.Both performance tests(DSC and TPD)and structural characterizations(XRD,HRTEM,etc.)revealed that the synergistic role of in situ formed Mg_(6)MnO_(8) and Mg_(2)NiH_(4)/Mg_(2)Ni phases for improving the hydrogen sorption properties of MgH_(2).Theoretical calculations reveal that Mg_(6)MnO_(8) destabilizes metal-H bonds in MgH_(2) and Mg_(2)NiH_(4),leading to an enhanced“hydrogen pump”effect of Mg_(2)NiH_(4) for MgH_(2).This research provides a strategy to rational design and preparation of bimetal MOF derivatives for the development of advanced hydrogen storage materials.展开更多
基金financially supported by the Key Research and Development Projects of Shaanxi Province(Grant Nos.2025CYYBXM-154 and 2024GX-YBXM-213)the Yulin Science and Technology Bureau(Grant Nos.2023-CXY-202 and 2024-CXY-154)+2 种基金the Scientific Research Program Funded by Shaanxi Provincial Education Department(Grant No.23JP008)the Natural Science Foundation of Qinghai Province for Distinguished Young Scholars(Grant No.2025-ZJ-966J)the Talent youth project of Chinese Academy of Sciences(Grant No.E410GC03)。
文摘Magnesium-based solid-state hydrogen storage materials(Mg-HSMs)exhibit significant potential for the global energy transition due to their large hydrogen capacity and energy density.However,their high operating temperatures,low operating efficiencies,and short service life have severely hindered largescale applications.To address the above challenges,diverse modification strategies have been proposed.Catalytic modification,achieved by introducing catalysts to enable compositional compounding and structural refinement,enhances surface active site density and bulk hydrogen diffusion pathways,reduces hydrogen dissociation energy barriers,weakens Mg–H bonds,and significantly improves kinetic properties.This approach is considered one of the most effective strategies.However,as research advances,the structures,forms,and catalytic mechanisms of catalysts have become increasingly diverse.Despite progress,challenges such as fragmented research outcomes,inconsistent performance metrics,and an incomplete understanding of structure-property relationships remain unresolved.Therefore,this work systematically summarizes recent advances in catalytic modification strategies for Mg-HSMs,emphasizing the role of catalysts in enhancing reaction kinetics and structural stability,the diversity of catalyst types,forms,and the underlying mechanisms governing catalytic efficacy.Based on critical analysis,this work identifies the current key technical bottlenecks and proposes that the design of next-generation catalysts and the future development of Mg-HSMs should be guided by the principles of‘multiphase heterogeneous interfacial composites'and‘synergistic development',aiming to provide theoretical guidance for the optimization and advancement of their performance.
基金Project supported by the Science and Technology Department of Jiangsu Province(BE2016769)the Natural Science Foundation of China(51172107)+2 种基金Natural Science Foundation of the Jiangsu Higher Education Institutions of China(14KJB430014)Open fund by Jiangsu Engineering Technology Research Center of Environmental Cleaning Materials(KFK1503)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘NiMnO3 perovskite catalysts supported on cordierite modified by CexZr（1-x）O2 coatings were prepared using impregnation and sol-gel methods for catalytic combustion of single/double component VOCs at different concentrations and GHSV of 15,000 h^（-1）, which were characterized by BET, XRD, SEM, FT-IR, H2-TPR and O2-TPD. After coating modification, the specific surface area of catalysts is improved obviously.Among the catalysts, the Ce（0.75）Zr（0.25）O2 coating modified NiMnO3 catalyst exhibits the best catalytic activity for VOCs combustion with 95.6% conversion at 275 ℃ and has stable activity when catalyst is embalmed at 800 ℃. In addition, the catalyst also presents the excellent water-resistant and conversion stability over time-on-stream condition. The reason is that Ce（0.75）Zr（0.25）O2 coating can promote more lattice distortion and defects and smaller crystal size, which improve oxygen transfer capability and dispersion of active component.
基金Funded by the National Basic Research Program of China(973 Program,2012CB720302)the Program for Changjiang Scholars and Innovative Research Team in University(No.IRT1161)the Corps Science and Technology Innovation Team Scheme(2011CC001)
文摘Commercial spherical activated carbon（SAC） was modified by impregnation to enhance the catalytic properties of SAC in acetylene hydrochlorination through melamine modification. Different modification conditions for SAC with nitrogen were compared by changing the SAC-Melamine ratios. The effect of carbonization temperature on the modification was also investigated. Surface chemistry and adsorption properties of the modified and unmodified SACs were studied by scanning electron microscope（SEM）, X-ray photoelectron spectroscopy（XPS）, elementary analysis, BET, and temperature-programmed desorption（TPD）. Moreover, the catalytic properties of SAC in acetylene hydrochlorination under differently modified conditions were also investigated. Elemental analysis showed that the nitrogen content of the modified SAC was greatly improved. XPS revealed that nitrogen mainly exists in Pyrrole nitrogen and Pyridine nitrogen. TPD showed that desorption of C2H2 was changed by modification. The conversion rate of acetylene was up to 70% under the following reaction conditions： temperature, 150 ℃; C2H2 hourly space velocity（GHSV）, 36 h-1; feed volume ratio V（HCl）/V（C2H2） = 1.15. The catalytic properties of SAC were improved significantly via melamine modification.
基金the support from the National Natural Science Foundation(No.52171186)National Key Research&Development Program(2022YFB3803700)of China.
文摘Hydrogen holds the advantages of high energy density,great natural abundance and zero emission,making it suitable for large scale and long term energy storage,while its safe and efficient storage is still challenging.Among various solid state hydrogen storage materials,MgH_(2) is promising for industrial applications due to its high gravimetric and volumetric hydrogen densities and the abundance of Mg on earth.However,the practical application of MgH_(2) has been limited by its stable thermodynamics and slow hydrogen desorption kinetics.Nanocatalysis is considered as a promising approach for improving the hydrogen storage performance of MgH_(2) and bringing it closer to the requirements of commercial applications.It is worth mentioning that the recently emerging two-dimensional material,MXene,has showcased exceptional catalytic abilities in modifying the hydrogen storage properties of MgH_(2).Besides,MXene possesses a high surface area,excellent chemical/physical stability,and negatively charged terminating groups,making it an ideal support for the"nanoconfinement"of MgH_(2) or highly active catalysts.Herein,we endeavor to provide a comprehensive overview of recent investigations on MXene-based catalysts and MXene supports for improving the hydrogen sorption properties of Mg/MgH_(2).The mechanisms of hydrogen sorption involved in Mg-MXene based composites are highlighted with special emphases on thermodynamics,kinetics,and catalytic behaviors.The aim of this work is to provide a comprehensive and objective review of researches on the development of high-performance catalysts/supports to improve hydrogen storage performances of Mg/MgH_(2) and to identify the opportunities and challenges for future applications.
基金Project supported by the National Natural Science Foundation of China(21266017,21566028,21566029)Research Fund for the Doctoral Program of Higher Education of China(20111514110001)Inner Mongolia Natural Science Foundation(2014MS0220,2015BS0206)
文摘The Cu-Mn catalysts doped with different amounts of lanthanum（La） for water-gas shift reaction（WGSR） were prepared, and characterized by X-ray diffraction（XRD）, temperature-programmed reduction（TPR）, temperature-programmed reduction of oxidized surfaces（s-TPR）, temperature-programmed desorption of CO_2（CO_2-TPD）, infrared spectrum（FT-IR） and X-ray photoelectron spectroscopy（XPS）. Catalytic activities were tested for a water-gas shift reaction. The results showed that the introduction of 0.5 mol.% La could significantly improve the catalyst activity for low-temperature shift reaction compared with the undoped catalyst, which might be from the introduction of La making the Cu and Mn components distribute uniformly and the synergistic effect between Cu and Mn increasing the dispersion of Cu on the surface of the catalyst. The apparent CuO phases besides Cu_（1.5）Mn_（1.5）O_4 were found in the samples with at least 3.0 mol.% La content, and the basic sites increased with the increasing of La contents at a decreased rate. With excessive La doping, La particles would aggregate and cover some active sites, resulting in that Mn could not effectively inhibit the gathering together and growing up of Cu crystalline grain, and decreased the dispersion of Cu on the surface, which resulted in the poor activity of the catalyst for WGSR.
基金the National Key Research&Development Program(2023YFB4005401),National Defense Basic Research Program(WDZC202202)and Prof.Zou would like to thank the support from National Natural Science Foundation(No.52171186)and Special Project for Peak Carbon Dioxide Emissions-Carbon Neutrality(No.21DZ1208200)from the Shanghai Municipal Science and Technology Commission.The authors also appreciate the financial support from the Center of Hydrogen Science,Shanghai Jiao Tong University.
文摘In the present work,highly effective Ni-MnO binary nanocomposite catalysts were designed and synthesized using a one-pot method from Ni-Mn based bi-metal organic frameworks(MOFs).These nanocomposites were introduced into MgH_(2) through ball milling as catalysts to enhance the hydrogen storage properties of MgH_(2).Through varying the Ni/Mn ratio in the bimetal MOFs,it is found that the Ni_(1)Mn_(1)-MOF derived catalyst showed the best promotion effect on MgH_(2).The MgH_(2)-10 wt.%Ni_(1)Mn_(1)-MOF derivative demonstrated favorable overall performance with the low desorption peak temperature(218.2℃)with a saturated hydrogen capacity of 6.42 wt.%and rapid hydrogen release/uptake kinetics.It can still reabsorb about 1.15 wt.%H_(2) within 30 min at a temperature as low as 50℃.Both performance tests(DSC and TPD)and structural characterizations(XRD,HRTEM,etc.)revealed that the synergistic role of in situ formed Mg_(6)MnO_(8) and Mg_(2)NiH_(4)/Mg_(2)Ni phases for improving the hydrogen sorption properties of MgH_(2).Theoretical calculations reveal that Mg_(6)MnO_(8) destabilizes metal-H bonds in MgH_(2) and Mg_(2)NiH_(4),leading to an enhanced“hydrogen pump”effect of Mg_(2)NiH_(4) for MgH_(2).This research provides a strategy to rational design and preparation of bimetal MOF derivatives for the development of advanced hydrogen storage materials.
