There has been a continuous effort to improve the thermal stability of subnanometric platinum(Pt)cluster(<2 nm) catalyst because Pt cluster on CeO_(2) support can be mobile and aggregated into nanoparticle on heati...There has been a continuous effort to improve the thermal stability of subnanometric platinum(Pt)cluster(<2 nm) catalyst because Pt cluster on CeO_(2) support can be mobile and aggregated into nanoparticle on heating at elevated temperatures,yet this great challenge remains.In this study,a strategy is reported to improve the thermal stability of subnanometric Pt cluster by hydrothermal deposition method.Based on this method,zirconium(Zr) was precisely doped on surface of Ce_(0.95)Zr_(0.05)O_(2) by accurately controlling Pt subnanometric cluster size.The surface doping of Zr is favorable for forming the Zr-O-Ce site and activating surface lattice oxygen atoms,which results in strong electronic interactions to stabilize the Pt subnanometric cluster.After high-temperature aging treatment at 1000℃/4 h,the single atom Pt supported on CeO_(2) is aggregated into larger sized(>3 nm) nanoparticle.In contrast,the single atom Pt supported on Ce_(0.95)Zr_(0.0)5O_(2) displays less agglomeration into subnanometric cluster with size of(1.4±0.3) nm.Moreover,the CO oxide catalytic performance of Ce_(0.95)Zr_(0.0)5O_(2)-Pt is 26% and 31%higher than that of CeO_(2)-Pt and commercial Al_(2)O_(3)-Pt catalysts,respectively.The experimental and density functional theory(DFT) calculations indicate that the Zr-O-Ce site and Pt subnanometric cluster interface have more defect sites and active oxygen species than CeO_(2)-Pt interface,which activate the Mars van Krevelen(MvK) mechanism,facilitating the catalytic performance.展开更多
Propane dehydrogenation(PDH)offers a promising route for on-demand propylene production,yet developing costeffective and durable non-noble metal catalysts remains challenging.Herein,we report a silanol(Si-OH)stabilize...Propane dehydrogenation(PDH)offers a promising route for on-demand propylene production,yet developing costeffective and durable non-noble metal catalysts remains challenging.Herein,we report a silanol(Si-OH)stabilized Zn catalyst supported on hierarchical self-pillared pentasil(SPP)zeolite,synthesized via the metal-ligand protection strategy under one-pot hydrothermal condition.The abundant isolated silanol groups on the SPP framework effectively anchor Zn^(2+) ions,forming highly dispersed subnanometric ZnO clusters confined within zeolite channels without forming bulk particles.Structural characterization(powder X-Ray diffraction(PXRD),Fourier transform infrared(FTIR),high-angle annular dark-field scanning transmission electron microscopy(HAADF-STEM),X-ray photoelectron spectroscopy(XPS))confirms the atomic-level dispersion of Zn species and their strong interaction with silanol defects.At an optimal Zn loading of 2.65 wt.%,the catalyst achieves 33.7%propane conversion with 92.7%propylene selectivity and a space-time yield of 179.9 mg·g^(−1)·h^(−1) at 550℃ under a weight hourly space velocity(WHSV)of 0.6 h^(−1).Remarkably,the catalyst retains>90%selectivity and recovers 80%initial activity after two regeneration cycles,attributed to minimized coke deposition(<0.3 wt.%)and suppressed Zn loss.Mechanistic studies reveal that silanol-mediated Zn stabilization optimizes propane C-H activation,while the hierarchical porosity of SPP enhances mass transport and coke resistance.This work underscores the critical role of support surface chemistry and architecture in designing robust propane dehydrogenation(PDH)catalysts,offering a viable pathway to replace conventional noble or toxic metal-based systems.展开更多
Long-chain alkanes are abundant feedstocks supplied by natural resources and chemical industry. Specially, normal long-chain alkanes are primary products from Fischer-Tropsch synthesis(FTS) process, which is an import...Long-chain alkanes are abundant feedstocks supplied by natural resources and chemical industry. Specially, normal long-chain alkanes are primary products from Fischer-Tropsch synthesis(FTS) process, which is an important route for the utilization of coal in China. Facing a shift of energy nexus towards sustainable society, the conversion of long-chain alkanes derived from coal into value-added products(such as alkenes and oxygenates) is of great importance for securing China’s energy supply and the role transition of the commercial FTS plants from fuel makers to chemical suppliers. Among the potential transformation routes,the direct dehydrogenation of long-chain alkanes into alkenes is an attractive and practical route, due to the broad applications of long-chain alkenes(especially the linear α-olefins). In this review, we will summary the key insights obtained from the literature on the dehydrogenation of light alkanes based on supported metal catalysts and the dehydrogenation of alkanes with homogeneous molecular catalysts and then discuss how to translate these lessons into the development of efficient catalysts and processes for the dehydrogenation of long-chain alkanes into long-chain alkenes.展开更多
基金supported by National Natural Science Foundation of China (52204376)Youth Foundation of Hebei Province (E2022103007)+1 种基金Open Project of Yunnan Precious Metals Laboratory Co.(YPML-20240502059)Young Elite Scientists Sponsorship Program by CAST (2021QNRC001)。
文摘There has been a continuous effort to improve the thermal stability of subnanometric platinum(Pt)cluster(<2 nm) catalyst because Pt cluster on CeO_(2) support can be mobile and aggregated into nanoparticle on heating at elevated temperatures,yet this great challenge remains.In this study,a strategy is reported to improve the thermal stability of subnanometric Pt cluster by hydrothermal deposition method.Based on this method,zirconium(Zr) was precisely doped on surface of Ce_(0.95)Zr_(0.05)O_(2) by accurately controlling Pt subnanometric cluster size.The surface doping of Zr is favorable for forming the Zr-O-Ce site and activating surface lattice oxygen atoms,which results in strong electronic interactions to stabilize the Pt subnanometric cluster.After high-temperature aging treatment at 1000℃/4 h,the single atom Pt supported on CeO_(2) is aggregated into larger sized(>3 nm) nanoparticle.In contrast,the single atom Pt supported on Ce_(0.95)Zr_(0.0)5O_(2) displays less agglomeration into subnanometric cluster with size of(1.4±0.3) nm.Moreover,the CO oxide catalytic performance of Ce_(0.95)Zr_(0.0)5O_(2)-Pt is 26% and 31%higher than that of CeO_(2)-Pt and commercial Al_(2)O_(3)-Pt catalysts,respectively.The experimental and density functional theory(DFT) calculations indicate that the Zr-O-Ce site and Pt subnanometric cluster interface have more defect sites and active oxygen species than CeO_(2)-Pt interface,which activate the Mars van Krevelen(MvK) mechanism,facilitating the catalytic performance.
基金supported by the National Key Research and Development Program of China(No.2021YFA1500503)the National Natural Science Foundation of China for Single-Atom Catalysis(No.22388102)+3 种基金the National Natural Science Foundation of China(Nos.22302218,22102210,22302199,22378079,and 21961142006)Natural Science Foundation of Shandong Province(No.ZR2024QB299)the Program for High-level Innovative Talents in Guizhou Province(No.GCC[2023]049)Energy Revolution Science and Technology Special Project(Joint Fund)of the Yulin Innovation Institute of Clean Energy(No.E411040316).
文摘Propane dehydrogenation(PDH)offers a promising route for on-demand propylene production,yet developing costeffective and durable non-noble metal catalysts remains challenging.Herein,we report a silanol(Si-OH)stabilized Zn catalyst supported on hierarchical self-pillared pentasil(SPP)zeolite,synthesized via the metal-ligand protection strategy under one-pot hydrothermal condition.The abundant isolated silanol groups on the SPP framework effectively anchor Zn^(2+) ions,forming highly dispersed subnanometric ZnO clusters confined within zeolite channels without forming bulk particles.Structural characterization(powder X-Ray diffraction(PXRD),Fourier transform infrared(FTIR),high-angle annular dark-field scanning transmission electron microscopy(HAADF-STEM),X-ray photoelectron spectroscopy(XPS))confirms the atomic-level dispersion of Zn species and their strong interaction with silanol defects.At an optimal Zn loading of 2.65 wt.%,the catalyst achieves 33.7%propane conversion with 92.7%propylene selectivity and a space-time yield of 179.9 mg·g^(−1)·h^(−1) at 550℃ under a weight hourly space velocity(WHSV)of 0.6 h^(−1).Remarkably,the catalyst retains>90%selectivity and recovers 80%initial activity after two regeneration cycles,attributed to minimized coke deposition(<0.3 wt.%)and suppressed Zn loss.Mechanistic studies reveal that silanol-mediated Zn stabilization optimizes propane C-H activation,while the hierarchical porosity of SPP enhances mass transport and coke resistance.This work underscores the critical role of support surface chemistry and architecture in designing robust propane dehydrogenation(PDH)catalysts,offering a viable pathway to replace conventional noble or toxic metal-based systems.
基金supported by Tsinghua University(Initiative Scientific Research Program 20211080079)the National Natural Science Foundation of China(21972161,22172186)+7 种基金Chinese Academy of Sciences(CAS)Pioneer Talents Program(2018-095)Shanxi Talent Program(2019SBRJH01)Autonomous Research Project of State Key Laboratory of Coal Conversion(SKLCC)(2020BWZ006,2021BWZ007)Institute of Coal Chemistry(ICC)Innovation Fund(SCJJ-2020-02)Inner Mengolia Science&Technology Project Plan(2021GG0311)Major science and technology project of Ordos(2022EEDSKJZDZX001)Start-Up Grant of Institute of Coal Chemistry(2020SC001)Synfuels China Co.,Ltd.
文摘Long-chain alkanes are abundant feedstocks supplied by natural resources and chemical industry. Specially, normal long-chain alkanes are primary products from Fischer-Tropsch synthesis(FTS) process, which is an important route for the utilization of coal in China. Facing a shift of energy nexus towards sustainable society, the conversion of long-chain alkanes derived from coal into value-added products(such as alkenes and oxygenates) is of great importance for securing China’s energy supply and the role transition of the commercial FTS plants from fuel makers to chemical suppliers. Among the potential transformation routes,the direct dehydrogenation of long-chain alkanes into alkenes is an attractive and practical route, due to the broad applications of long-chain alkenes(especially the linear α-olefins). In this review, we will summary the key insights obtained from the literature on the dehydrogenation of light alkanes based on supported metal catalysts and the dehydrogenation of alkanes with homogeneous molecular catalysts and then discuss how to translate these lessons into the development of efficient catalysts and processes for the dehydrogenation of long-chain alkanes into long-chain alkenes.
