The physicochemical features of phosphorus-modified ZSM-5 zeolites (SiO2/Al2O3 molar ratio is 25) were characterized by XRD(X-ray diffraction), BET(Brunauer, Emmett and Teller spcific surface area measurement), NH3-TP...The physicochemical features of phosphorus-modified ZSM-5 zeolites (SiO2/Al2O3 molar ratio is 25) were characterized by XRD(X-ray diffraction), BET(Brunauer, Emmett and Teller spcific surface area measurement), NH3-TPD(ammonia temperature-programmed desorption) and MASNMR(magic angle spinning nuclear magnetic resonance), and the performance on catalytic pyrolysis to produce ethylene was investigated with a light hydrocarbon fixed bed micro-reactor with n-octane as feed. The results show that the acid site density, acid intensity and hydrothermal stability of ZSM-5 zeolite were improved by phosphorus modification. When P2O5 content in ZSM-5 zeolite is higher than 2.5%, phosphorus modification can prevent ZSM-5 zeolite crystal structure transformation from orthorhombic to monoclinic. In addition, the dealumination of ZSM-5 zeolite framework was moderated by phosphorus modification under high temperature hydrothermal treatment. The results of n-octane pyrolysis on phosphorus-modified ZSM-5 zeolites show that ethylene yields of zeolites with different phosphorus content are almost the same under the same n-octane conversion. However, the modified zeolites with higher pyrolysis activity give lower yield of propene, butene and total olefin than lower pyrolysis activity under the same n-octane conversion.展开更多
The sintering of Pt nanoparticles is one of the main reasons for catalyst deactivation during the high-temperature propane dehydrogenation(PDH) reaction. Promoters and supports have been introduced to prolong the cata...The sintering of Pt nanoparticles is one of the main reasons for catalyst deactivation during the high-temperature propane dehydrogenation(PDH) reaction. Promoters and supports have been introduced to prolong the catalyst life.However, it is still necessary to develop novel catalysts with robust stability. Herein, the phosphorus-modified carbon nanotube-supported Pt nanoparticles were employed for the PDH process. Phosphorus modification improves the Pt dispersion, effectively promoting the activity of Pt/P-CNTs. Additionally, the phosphorus-modified CNTs can interact strongly with Pt nanoparticles by improving the electron transfer or hybridization, stabilizing Pt nanoparticles from agglomeration, and significantly enhancing the catalyst stability.展开更多
Proton exchange membrane water electrolysis (PEMWE) requires Pt-based hydrogen evolution reaction (HER) electrocatalysts, which makes current systems costly. Low-cost alternatives have struggled to meet the requiremen...Proton exchange membrane water electrolysis (PEMWE) requires Pt-based hydrogen evolution reaction (HER) electrocatalysts, which makes current systems costly. Low-cost alternatives have struggled to meet the requirements of both electrocatalytic activity and durability at high-current density operations. Here, we developed phosphorus-modified nickel with ruthenium nanoclusters self-supported on carbon paper (P-NiRu/CP) as efficient HER electrocatalysts. By leveraging metal-organic framework precursors and optimizing the phosphidation process, a dynamic interface between Ru, Ni, and P exhibited optimized hydrogen adsorption/desorption energies and facilitated hydrogen mobility, promoting efficient Tafel recombination. The P-NiRu/CP exhibited an overpotential of 22 mV at 10 mA cm^(−2) and a Tafel slope of 29 mV dec^(−1), outperforming benchmark Pt/C. Computational studies revealed that the dynamic interface in P-NiRu/CP enhanced the electrocatalytic activity. When employed as the cathode in a PEMWE single cell (with commercial IrO2 as the anode) operating with pure deionized water, P-NiRu/CP achieved 2.05 V at 3.0 A cm^(−2) with stable operation over 500 h, highlighting P-NiRu/CP as a cost-effective, durable, and scalable electrocatalyst for sustainable hydrogen production.展开更多
文摘The physicochemical features of phosphorus-modified ZSM-5 zeolites (SiO2/Al2O3 molar ratio is 25) were characterized by XRD(X-ray diffraction), BET(Brunauer, Emmett and Teller spcific surface area measurement), NH3-TPD(ammonia temperature-programmed desorption) and MASNMR(magic angle spinning nuclear magnetic resonance), and the performance on catalytic pyrolysis to produce ethylene was investigated with a light hydrocarbon fixed bed micro-reactor with n-octane as feed. The results show that the acid site density, acid intensity and hydrothermal stability of ZSM-5 zeolite were improved by phosphorus modification. When P2O5 content in ZSM-5 zeolite is higher than 2.5%, phosphorus modification can prevent ZSM-5 zeolite crystal structure transformation from orthorhombic to monoclinic. In addition, the dealumination of ZSM-5 zeolite framework was moderated by phosphorus modification under high temperature hydrothermal treatment. The results of n-octane pyrolysis on phosphorus-modified ZSM-5 zeolites show that ethylene yields of zeolites with different phosphorus content are almost the same under the same n-octane conversion. However, the modified zeolites with higher pyrolysis activity give lower yield of propene, butene and total olefin than lower pyrolysis activity under the same n-octane conversion.
基金supported by the National Natural Science Foundation of China (Grant 21706036)the State Key Laboratory of Catalytic Materials and Reaction Engineering (RIPP, SINOPEC)the Natural Science Foundation of Fujian Province (Grant 2018J05019)
文摘The sintering of Pt nanoparticles is one of the main reasons for catalyst deactivation during the high-temperature propane dehydrogenation(PDH) reaction. Promoters and supports have been introduced to prolong the catalyst life.However, it is still necessary to develop novel catalysts with robust stability. Herein, the phosphorus-modified carbon nanotube-supported Pt nanoparticles were employed for the PDH process. Phosphorus modification improves the Pt dispersion, effectively promoting the activity of Pt/P-CNTs. Additionally, the phosphorus-modified CNTs can interact strongly with Pt nanoparticles by improving the electron transfer or hybridization, stabilizing Pt nanoparticles from agglomeration, and significantly enhancing the catalyst stability.
基金supported by the National R&D Program through the National Research Foundation of Korea(NRF),funded by the Ministry of Science and ICT,Republic of Korea(RS-2024-00409901 and RS-2025-02304646).
文摘Proton exchange membrane water electrolysis (PEMWE) requires Pt-based hydrogen evolution reaction (HER) electrocatalysts, which makes current systems costly. Low-cost alternatives have struggled to meet the requirements of both electrocatalytic activity and durability at high-current density operations. Here, we developed phosphorus-modified nickel with ruthenium nanoclusters self-supported on carbon paper (P-NiRu/CP) as efficient HER electrocatalysts. By leveraging metal-organic framework precursors and optimizing the phosphidation process, a dynamic interface between Ru, Ni, and P exhibited optimized hydrogen adsorption/desorption energies and facilitated hydrogen mobility, promoting efficient Tafel recombination. The P-NiRu/CP exhibited an overpotential of 22 mV at 10 mA cm^(−2) and a Tafel slope of 29 mV dec^(−1), outperforming benchmark Pt/C. Computational studies revealed that the dynamic interface in P-NiRu/CP enhanced the electrocatalytic activity. When employed as the cathode in a PEMWE single cell (with commercial IrO2 as the anode) operating with pure deionized water, P-NiRu/CP achieved 2.05 V at 3.0 A cm^(−2) with stable operation over 500 h, highlighting P-NiRu/CP as a cost-effective, durable, and scalable electrocatalyst for sustainable hydrogen production.
