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Effects of zinc on Fe-based catalysts during the synthesis of light olefins from the Fischer-Tropsch process 被引量:12
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作者 高新华 张建利 +4 位作者 陈宁 马清祥 范素兵 赵天生 椿范立 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第4期510-516,共7页
Fe‐based catalysts for the production of light olefins via the Fischer‐Tropsch synthesis were modi‐fied by adding a Zn promoter using both microwave‐hydrothermal and impregnation methods. The physicochemical prope... Fe‐based catalysts for the production of light olefins via the Fischer‐Tropsch synthesis were modi‐fied by adding a Zn promoter using both microwave‐hydrothermal and impregnation methods. The physicochemical properties of the resulting catalysts were determined by scanning electron mi‐croscopy, the Brunauer‐Emmett‐Teller method, X‐ray diffraction, H2 temperature‐programed re‐duction and X‐ray photoelectron spectroscopy. The results demonstrate that the addition of a Zn promoter improves both the light olefin selectivity over the catalyst and the catalyst stability. The catalysts prepared via the impregnation method, which contain greater quantities of surface ZnO, exhibit severe carbon deposition following activity trials. In contrast, those materials synthesized using the microwave‐hydrothermal approach show improved dispersion of Zn and Fe phases and decreased carbon deposition, and so exhibit better CO conversion and stability. 展开更多
关键词 Zn promoter fe-based catalyst Light olefin Fischer-Tropsch synthesis Microwave-hydrothermal method
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Oxygen Vacancy in CeO_(2)Enhanced Low-Temperature Ammonia Synthesis over Fe-Based Catalysts
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作者 Wangyang Ji Xiangrui Kong +4 位作者 Jiewei Zhu Minghao Guo Baoshun Zhang Tieliang Li Yifu Yu 《Transactions of Tianjin University》 2025年第4期403-410,共8页
Ammonia is essential for agriculture and,as a next-generation carbon-free fuel,typically produced through the Haber-Bosch method.This process requires high temperature and pressure,leading to significant energy consum... Ammonia is essential for agriculture and,as a next-generation carbon-free fuel,typically produced through the Haber-Bosch method.This process requires high temperature and pressure,leading to significant energy consumption and greenhouse gas emissions.Therefore,achieving ammonia synthesis under milder conditions has been a long-standing goal.In this study,we design and synthesize a series of CeO_(2)-modified Fe/carbon-based catalysts with varying amounts of CeO_(2)(Ce_(x)Fe_(y)/C).The catalyst Ce_(2)Fe_(5)/C demonstrates an ammonia yield rate of 3.5 mmol/(g·h),which is 44 times greater than that of Fe/C and 8 times greater than that of commercial Fe-based catalysts at 300℃and 1 MPa.Temperature-programmed desorption experiments show that Ce_(2)Fe_(5)/C has enhanced nitrogen adsorption capabilities.Multiple analyses confirm that the CeO_(2)in Ce_(2)Fe_(5)/C is rich in oxygen vacancies,which can provide electrons to Fe,facilitating nitrogen adsorption,dissociation,and activity in low-temperature ammonia synthesis. 展开更多
关键词 Ammonia synthesis Iron catalyst Oxygen vacancy Cerium dioxide
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Advancements in Thermo and Photothermal CO_(2) Hydrogenation to Light Olefins Using Fe-Based Catalysts:Current Progress and Future Directions
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作者 Timofey Karnaukhov Blaž Likozar Andrii Kostyniuk 《Carbon Energy》 2025年第10期54-86,共33页
The development of human industry inevitably leads to excessive carbon dioxide(CO_(2))emissions.It can cause critical ecological consequences,primarily global warming and ocean acidification.In this regard,close atten... The development of human industry inevitably leads to excessive carbon dioxide(CO_(2))emissions.It can cause critical ecological consequences,primarily global warming and ocean acidification.In this regard,close attention is paid to the carbon capture,utilization,and storage concept.The key component of this concept is the catalytic conversion of CO_(2)into valuable chemical compounds and fuels.Light olefins are one of the most industrially important chemicals,and their sustainable production via CO_(2)hydrogenation could be a prospective way to reach carbon neutrality.Fe-based materials are widely recognized as effective thermocatalysts and photothermal catalysts for that process thanks to their low cost,high activity,and good stability.This review critically examines the most recent progress in the development and optimization of Fe-based catalysts for CO_(2)hydrogenation into light olefins.Particular attention is paid to understanding the roles of catalyst composition,structural properties,and promoters in enhancing catalytic activity,selectivity,and stability. 展开更多
关键词 CO_(2)hydrogenation heterogeneous catalysts light olefins photothermal catalysis reaction mechanisms
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Regulating the location of metal promoters in CuFe-based catalysts for enhanced CO_(2)hydrogenation to higher alcohols
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作者 Qixin Fan Na Liu +8 位作者 Jingming Zhao Yang Yu Yannan Sun Yu Han Jixin Zhang Aimin Wang Qingjie Ge Jian Wei Jian Sun 《Journal of Energy Chemistry》 2025年第8期31-43,共13页
Regulating the location of the metal promoters plays a vital role in catalyst structure and its catalytic behavior during CO_(2)hydrogenation to higher alcohols.Herein,we selected the metal promoters with a precipitat... Regulating the location of the metal promoters plays a vital role in catalyst structure and its catalytic behavior during CO_(2)hydrogenation to higher alcohols.Herein,we selected the metal promoters with a precipitation pH similar to that of Cu^(2+)or Fe^(3+)to prepare a series of CuFe-based catalysts.Characterization results show that doping Al or Cr promoter,located with the Fe phase,suppressed the excessive carburization of the Fe phase and maintained an optimal proportion between Fe_(3)O_(4) and amorphous iron carbide(FeC_(x)),thus exhibiting superior catalytic activity and stability.In contrast,doping Zn or In promoter,located with the Cu phase,underwent a deeper carburization and formed more crys-talline FeC_(x),showing an inferior performance.The CuFeCr catalyst achieved the highest space-time yield of 330 mg g_(cat)^(-1)h^(-1)for higher alcohols among these catalysts.This study provides a novel strategy for opti-mizing the structure of the active phases for CO_(2)hydrogenation. 展开更多
关键词 CO_(2)hydrogenation CuFe bimetallic catalyst Metal modification Higher alcohols Amorphous iron carbide
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Denitrification characteristics and reaction mechanism of Ce-doped Fe-based catalysts from modified metallurgical dust containing iron 被引量:1
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作者 Zhi-fang Gao Hong-ming Long +1 位作者 Xiang-peng Gao Hao Zhang 《Journal of Iron and Steel Research International》 CSCD 2024年第12期2915-2926,共12页
Metallurgical dust(MD)was used as raw material to prepare rare earth Ce-doped Fe-based catalysts.The results show that the Ce_(0.1)/AMD-300℃catalyst prepared from acid-modified diatomite(AMD)with mCe/mMD=0.1(m_(Ce)an... Metallurgical dust(MD)was used as raw material to prepare rare earth Ce-doped Fe-based catalysts.The results show that the Ce_(0.1)/AMD-300℃catalyst prepared from acid-modified diatomite(AMD)with mCe/mMD=0.1(m_(Ce)and m_(MD)are the mass of Ce and MD,respectively)after being roasted at 300℃can reach 99%NO_(x)removal rate in the wide temperature range of 230–430℃and exhibits excellent So_(2)and H_(2)o resistance.The MD effectively removes alkali metal elements by the modification process,increases the specific surface area and optimizes the pore structure of MD.The doping of Ce element makes Fe-based catalysts have more surface adsorbed oxygen O_(α)and a higher Ce^(3+)/Ce^(4+)ratio.Through ammonia temperature-programmed desorption and hydrogen temperature-programmed reduction,it was found that the strong interaction between cerium and iron promotes the formation of more oxygen cavities in the catalyst,thereby generating more active and easily reducible oxygen species and promoting the transformation of Brønsted acid site to Lewis acid site.The research results provide a theoretical basis for the preparation of efficient and inexpensive Fe-based catalysts from MD. 展开更多
关键词 Metallurgical dust fe-based catalyst DENITRIFICATION Rare earth doping
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Effect of Several Anions on Fe-Based Catalyst for Fischer-Tropsch Synthesis
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作者 Jingchang Zhang Xuehua Guo Weiliang Cao 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2007年第4期377-381,共5页
The influence of several anions on Fe-based Fischer-Tropsch catalyst, used in the synthesis of light olefins from synthesis gas, was studied. The results indicated that the addition of anions resulted in the reduction... The influence of several anions on Fe-based Fischer-Tropsch catalyst, used in the synthesis of light olefins from synthesis gas, was studied. The results indicated that the addition of anions resulted in the reduction of catalytic activity. When the anion content in the catalyst was 500 ppm, the influence of different anions on the catalysis activity was as follows: S^2- 〉Cl^-〉SO4^2-〉NO3. The addition of S^2- improved the selectivity of total hydrocarbons in the products, and Cl^- reduced this selectivity but increased the olefin content in the total hydrocarbons at the same time. When the contents of S^2- and Clin the catalyst were less than 50 ppm, their influence could be ignored. The XRD results indicated that the addition of anions reduced the contents of α-Fe and FeaC, which were the active components in the catalyst. 展开更多
关键词 F-T synthesis ANIONS synthesis gas light olefins fe-based catalyst
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Hydrogen production by catalytic decomposition of methane using a Fe-based catalyst in a fluidized bed reactor 被引量:5
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作者 D.Torres S.deLlobet +3 位作者 J.L.Pinilla M.J.Lzaro I.Suelves R.Moliner 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2012年第4期367-373,共7页
Catalytic decomposition of methane using a Fe-based catalyst for hydrogen production has been studied in this work. A Fe/Al2O3 catalyst previously developed by our research group has been tested in a fluidized bed rea... Catalytic decomposition of methane using a Fe-based catalyst for hydrogen production has been studied in this work. A Fe/Al2O3 catalyst previously developed by our research group has been tested in a fluidized bed reactor (FBR). A parametric study ot the effects of some process variables, including reaction temperature and space velocity, is undertaken. The operating conditions strongly affect the catalyst performance. Methane conversion was increased by increasing the temperature and lowering the space velocity. Using temperatures between 700 and 900℃ and space velocities between 3 and 6 LN/(gcat·h), a methane conversion in the range of 25%-40% for the gas exiting the reactor could be obtained during a 6 h run. In addition, carbon was deposited in the form of nanofilaments (chain like nanofibers and multiwall nanotubes) with similar properties to those obtained in a fixed bed reactor. 展开更多
关键词 hydrogen production fluidized bed reactor metal catalysts
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A dual-site Fe-based catalyst for efficient ammonia synthesis under mild conditions
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作者 Shiyong Zhang Mingyuan Zhang +11 位作者 Tianhua Zhang Jizhen Sun Jiaxin Li Kailin Su Ruishao Mao Yanliang Zhou Xuanbei Peng Yangyu Zhang Jun Ni Bingyu Lin Xiuyun Wang Lilong Jiang 《Science China Chemistry》 2025年第4期1576-1584,共9页
Achieving green ammonia(NH_(3))synthesis requires developing effective catalysts under mild conditions.However;the competitive adsorption of N2 and H_(2);as well as the strong binding of N-containing intermediates on ... Achieving green ammonia(NH_(3))synthesis requires developing effective catalysts under mild conditions.However;the competitive adsorption of N2 and H_(2);as well as the strong binding of N-containing intermediates on the catalyst;greatly inhibits the active sites for efficient NH_(3) synthesis.Here;we constructed a series of ZrH_(2)-modified Fe catalysts with dual active sites to address these issues and realized efficient NH_(3) synthesis under mild conditions.Our study shows that ZrH_(2) can not only provide active sites for H_(2) activation but also transfer electrons to Fe sites for accelerating N2 activation.The interaction between Fe and ZrH_(2) over 40ZrH_(2)-Fe leads to a decrease in work function and a downward shift of the d-band center;which is conducive to N2 activation and NH_(3) desorption;respectively.The utilization of distinct sites for activating different reactants can avoid the competitive adsorption of N2 and H_(2);leading to excellent NH_(3) synthesis activity of the 40 wt.%ZrH_(2)-mediated Fe catalyst.As a result;40ZrH_(2)-Fe exhibits a high NH_(3) synthesis rate of 23.3 mmol gcat-1h-1at 400℃and 1 MPa and robust stability during 100 h time-on-stream. 展开更多
关键词 ammonia synthesis competitive adsorption dual-site catalyst N2 activation synergistic effect
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Fe-based catalysts for nitrogen reduction toward ammonia electrosynthesis under ambient conditions 被引量:5
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作者 Haiding Zhu Xuefeng Ren +3 位作者 Xiaoxuan Yang Xingyou Liang Anmin Liu Gang Wu 《SusMat》 2022年第3期214-242,共29页
As one of the most important chemicals and carbon-free energy carriers,ammonia(NH3)has significant energy-related applications in industry and agriculture.Ninety percent of NH_(3) is produced by the Haber-Bosch proces... As one of the most important chemicals and carbon-free energy carriers,ammonia(NH3)has significant energy-related applications in industry and agriculture.Ninety percent of NH_(3) is produced by the Haber-Bosch process using high-purity N_(2) and H_(2) at high temperatures and pressures,which consumes about 1%of the total energy production and causes 1.4% of global CO_(2) emissions.The environmentally friendly electrochemical nitrogen reduction reaction(NRR)with low energy consumption is a promising alternative to the conventional Haber-Bosch process.However,the main issue is the low Faradaic efficiency and NH3 selectivity of electrochemical NRR,caused by inert nitrogen molecules and competitive hydrogen evolution reaction.As one of the cheapest and most abundant transition metals widely utilized in the Haber-Bosch process,the Fe element has presented the potential high performance for the electrochemical NRR.This article summarizes recent advances and research progress in non-noble Fe-based catalysts used for NH_(3) electrosynthesis.Various synthetic protocols,structure/morphology modification,performance improvement,and reaction mechanisms are comprehensively presented.Based on recent experimental and theoretical studies,we aim to illuminate the structure-property relationship and offer an excellent opportunity for engineering advanced Fe-based catalysts for nitrogen fixation.The most critical challenges and opportunities for Fe-based catalysts are also provided.This review would open up a promising avenue toward developing platinum-group-metal-free catalysts for electrochemical NRR applications in the future. 展开更多
关键词 electrochemical NRR Faradic efficiency fe-based catalysts NH_(3)production NH_(3)selectivity
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Anion modulate the morphological and electronic structure of NiFe-based electrocatalyst for efficient urea oxidation-assisted water electrolysis
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作者 Duowen Ma Yansong Jia +9 位作者 Yang Li Haibin Yang Fengzhi Wang Xinyu Zheng Guining Shao Qi Xiong Zhihao Shen Min Liu Zirui Lou Chaohua Gu 《Journal of Materials Science & Technology》 CSCD 2024年第30期207-214,共8页
Renewable energy-driven water electrolysis is considered as an environmentally friendly hydrogen(H2)production technology.Replacing the oxygen evolution reaction(OER)with the urea oxidation reaction(UOR)is a more effe... Renewable energy-driven water electrolysis is considered as an environmentally friendly hydrogen(H2)production technology.Replacing the oxygen evolution reaction(OER)with the urea oxidation reaction(UOR)is a more effective way to improve the energy efficiency of H2 generation.Herein,a highly effi-cient 2D NiFeMo-based UOR catalyst and 1D NiFeMo-based HER catalyst are prepared by adjusting the concentration of MoO_(4)^(-).The MoO_(4)^(-)can serve as the key regulator to adjust the balance between the electrolytic dissociation(α)of the reactants and the supersaturation(S)to modulate the morphological and electronic structure.The prepared 2D NiFeMo nanosheet UOR catalyst and 1D NiFeMo nanorod HER catalyst can achieve a current density of 100 mA cm^(−2)at a potential of 1.36 and 0.062 V,respectively.In a HER/UOR system,a cell voltage of 1.58 V is needed to achieve a current density of 100 mA cm^(−2).The HER/UOR system operated stably for over 60 h with 3 times the direct water electrolysis current den-sity.Moreover,the in situ Raman characterization coupled with XPS analysis clarifies that the addition of high-valence Mo can lower the transition energy barrier between the low and high oxidation state of Ni,which in turn lowers the overpotential of UOR.This work provides a novel strategy for synthesizing morphology-dependent electrocatalysts for different catalytic systems. 展开更多
关键词 Urea oxidation reaction Nife-based catalyst Hydrogen evolution Morphological and electronic structure Active sites
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Emerging modification strategies for layered Fe-based oxide cathodes toward high-performance sodium-ion batteries 被引量:1
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作者 Zheng-Xiao Li Yi-Meng Wu +6 位作者 Jun-Wei Yin Peng-Fei Wang Zong-Lin Liu Yan-Xuan Wen Jun-Hong Zhang Yan-Rong Zhu Ting-Feng Yi 《Journal of Energy Chemistry》 2025年第8期122-147,共26页
Sodium-ion batteries(SIBs)have the advantages of environmental friendliness,cost-effectiveness,and high energy density,which are considered one of the most promising candidates for lithium-ion batteries(LIBs).The cath... Sodium-ion batteries(SIBs)have the advantages of environmental friendliness,cost-effectiveness,and high energy density,which are considered one of the most promising candidates for lithium-ion batteries(LIBs).The cathode materials influence the cost and energy output of SIBs.Therefore,the development of advanced cathode materials is crucial for the practical application of SIBs.Among various cathode materials,layered transition metal oxides(LTMOs)have received widespread attention owing to their straightforward preparation,abundant availability,and cost-competitiveness.Notably,layered Fe-based oxide cathodes are deemed to be one of the most promising candidates for the lowest price and easy-to-improve performance.Nevertheless,the challenges such as severe phase transitions,sluggish diffusion kinetics and interfacial degradation pose significant hurdles in achieving high-performance cathodes for SIBs.This review first briefly outlines the classification of layered structures and the working principle of layered oxides.Then,recent advances in modification strategies employed to address current issues with layered iron-based oxide cathodes are systematically reviewed,including ion doping,biphasic engineering and surface modification.Furthermore,the review not only outlines the prospects and development directions for layered Fe-based oxide cathodes but also provides novel insights and directions for future research endeavors for SIBs. 展开更多
关键词 Layered fe-based oxide cathodes lon doping Biphasic engineering Surface modification Sodium-ion batteries
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Unregulated emissions from diesel engine with particulate filter using Fe-based fuel borne catalyst 被引量:5
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作者 Hong Zhao Yunshan Ge +3 位作者 Tiezhu Zhang Jipeng Zhang Jianwei Tan Hongxin Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2014年第10期2027-2033,共7页
The alteration and formation of toxic compounds and potential changes in the toxicity of emissions when using after-treatment technologies have gained wide attention. Volatile organic compound(VOC), carbonyl compoun... The alteration and formation of toxic compounds and potential changes in the toxicity of emissions when using after-treatment technologies have gained wide attention. Volatile organic compound(VOC), carbonyl compound and particle-phase polycyclic aromatic hydrocarbon(PAH) emissions were tested at European Steady State Cycle(ESC) to study unregulated emissions from a diesel engine with a fuel-borne catalyst and diesel particulate filter(FBC–DPF). An Fe-based fuel-borne catalyst was used for this study. According to the results, brake specific emissions of total VOCs without and with DPF were 4.7 and4.9 mg/kWh, respectively, showing a 4.3% increase. Benzene and n-undecane emissions increased and toluene emission decreased, while other individual VOC emissions basically had no change. When retrofitted with the FBC–DPF, total carbonyl compound emission decreased 15.7%, from 25.8 to 21.8 mg/kWh. The two highest carbonyls, formaldehyde and acetaldehyde, were reduced from 20.0 and 3.7 to 16.5 and 3.3 mg/kWh respectively. The specific reactivity(SR) with DPF was reduced from 6.68 to 6.64 mg/kWh. Total particle-phase PAH emissions decreased 66.4% with DPF compared to that without DPF. However, the Benzo[a]pyrene equivalent(BaPeq) with DPF had increased from 0.016 to 0.030 mg/kWh.Fluoranthene and Pyrene had the greatest decrease, 91.1% and 88.4% respectively. The increase of two- and three-ring PAHs with DPF indicates that the fuel-borne catalyst caused some gas-phase PAHs to adsorb on particles. The results of this study expand the knowledge of the effects of using a particulate filter and a Fe-based fuel-borne catalyst on diesel engine unregulated emissions. 展开更多
关键词 Fuel-borne catalyst DPF VOCs Carbonyl compounds Particle-phase PAHs
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A fast and in-depth self-reconstruction of anion ligands optimized CoFe-based pre-catalysts for water oxidation 被引量:1
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作者 Qiuyan Jin Hao Cui Chengxin Wang 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第3期812-819,共8页
The design of efficient and robust non-precious metal electrocatalysts towards oxygen evolution reaction(OER)is of great value for developing green energy technologies.The in-situ formed high-valence(oxy)hydroxides sp... The design of efficient and robust non-precious metal electrocatalysts towards oxygen evolution reaction(OER)is of great value for developing green energy technologies.The in-situ formed high-valence(oxy)hydroxides species during the reconstruction process of pre-catalysts are recognized as the real contributing sites for OER.However,pre-catalysts generally undergo a slow and inadequate self-reconstruction.Herein,we reported a PO^(3-)_(4)optimized CoFe-based OER catalysts with amorphous structure,which enables a fast and deep reconstruction during the OER process.The amorphous structure induced by ligands PO^(3-)_(4)is prone to evolution and further form active species for OER.The electron interaction between metal sites can be modulated by electron-rich PO^(3-)_(4),which promotes generation of high active CoOOH.Simultaneously,the etching of PO^(3-)_(4)from the pre-catalysts during the catalytic process is in favor of accelerating the self-reconstruction.As a result,as-prepared precatalyst can generate high active CoOOH at a low potential of 1.4 V and achieve an in-depth reconstructed nanosheet structure with abundant OER active sites.Our work provides a promising design of pre-catalysts for realizing efficient catalysis of water oxidation. 展开更多
关键词 Oxygen evolution reaction Pre-catalysts Reconstruction Anion ligands Bimetallic catalysts
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Review of rare earth oxide doping-modified laser cladding of Fe-based alloy coatings
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作者 Han-yu Zhou Li-yao Li +4 位作者 Yang Zhao Ming-xue Shen Huo-ping Zhao Ye-long Xiao Shao-peng Liu 《China Foundry》 2025年第1期12-22,共11页
Conventional Fe-C alloy parts used in mechanical transmission and braking systems exposed to the external environment often suffer from wear and corrosion failures.Surface coating strengthening technologies have been ... Conventional Fe-C alloy parts used in mechanical transmission and braking systems exposed to the external environment often suffer from wear and corrosion failures.Surface coating strengthening technologies have been explored to improve the surface performance and prolong service life of these parts.Among these technologies,laser cladding has shown promise in producing Fe-based alloy coatings with superior interfacial bonding properties to the Fe-C alloy substrate.Additionally,the microstructure of the Fe-based alloy coating is more uniform and the grain size is finer than that of surfacing welding,thermal spraying,and plasma cladding,and the oxide film of alloying elements on the coating surface can improve the coating performance.However,Fe-based alloy coatings produced by laser cladding typically exhibit lower hardness,lower wear resistance,corrosion resistance,and oxidation resistance compared to coatings based on Co and Ni alloys.Moreover,these coatings are susceptible to defects such as pores and cracks.To address these limitations,the incorporation of rare-earth oxides through doping in the laser cladding process has garnered significant attention.This approach has demonstrated substantial improvements in the microstructure and properties of Fe-based alloy coatings.This paper reviewed recent research on the structure and properties of laser-cladded Fe-based alloy coatings doped with various rare earth oxides,including La_(2)O_(3),CeO_(2),and Y_(2)O_(3).Specifically,it discussed the effects of rare earth oxides and their concentrations on the structure,hardness,friction,wear,corrosion,and oxidation characteristics of these coatings.Furthermore,the mechanisms by which rare earth oxides influence the coating’s structure and properties were summarized.This review aimed to serve as a valuable reference for the application and advancement of laser cladding technology for rare earth modified Fe-based alloy coatings. 展开更多
关键词 fe-based alloys laser cladding rare-earth oxides MICROSTRUCTURE tribological properties
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Enhancement of bending toughness for Fe-based amorphous nanocrystalline alloy with deep cryogenic-cycling treatment
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作者 Yi-ran Zhang Dong Yang +5 位作者 Qing-chun Xiang Hong-yu Liu Jing Pang Ying-lei Ren Xiao-yu Li Ke-qiang Qiu 《China Foundry》 2025年第1期99-107,共9页
The effects of deep cryogenic-cycling treatment(DCT)on the mechanical properties,soft magnetic properties,and atomic scale structure of the Fe_(73.5)Si_(13.5)B_(9)Nb_(3)Cu_(1)amorphous nanocrystalline alloy were inves... The effects of deep cryogenic-cycling treatment(DCT)on the mechanical properties,soft magnetic properties,and atomic scale structure of the Fe_(73.5)Si_(13.5)B_(9)Nb_(3)Cu_(1)amorphous nanocrystalline alloy were investigated.The DCT samples were obtained by subjecting the as-annealed samples to a thermal cycling process between the temperature of the supercooled liquid zone and the temperature of liquid nitrogen.Through flat plate bending testing,hardness measurements,and nanoindentation experiment,it is found that the bending toughness of the DCT samples is improved and the soft magnetic properties are also slightly enhanced.These are attributed to the rejuvenation behavior of the DCT samples,which demonstrate a higher enthalpy of relaxation.Therefore,DCT is an effective method to enhance the bending toughness of Fe-based amorphous nanocrystalline alloys without degrading the soft magnetic properties. 展开更多
关键词 deep cryogenic-cycling treatment fe-based amorphous nanocrystalline alloy bending toughness REJUVENATION
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Synchronously enhancing the plasticity and soft magnetism in Fe-based metallic glasses through memory effect
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作者 Weihua Zhou Shiyuan Zhang +3 位作者 Lijian Song Juntao Huo Jun-Qiang Wang Yi Li 《Journal of Materials Science & Technology》 2025年第10期146-152,共7页
Annealing has been a popular method to improve the soft magnetism of metallic glasses (MGs), which however usually makes MGs brittle and difficult to process. Here, it is demonstrated that the embrittled Fe-based MG c... Annealing has been a popular method to improve the soft magnetism of metallic glasses (MGs), which however usually makes MGs brittle and difficult to process. Here, it is demonstrated that the embrittled Fe-based MG can be reductilized and the coercivity can be further lowered through the rejuvenation of memory effect. The synchronous improvement in the plasticity and soft magnetic properties is attributed to the combination effects of releasing much residual stress, decreasing the magnetic anisotropy, and homogenizing the glasses during the rejuvenation process. The current work opens a new perspective to improve the properties of MGs by utilizing the memory effect and holds promising commercial application potential. 展开更多
关键词 Memory effect REJUVENATION Reductilization Soft magnetism fe-based metallic glass
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Structure-activity correlation mechanism of additive-modified Cu-based catalysts for methanol synthesis via CO_(2)hydrogenation
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作者 HUANG Wenbin SI Meng +4 位作者 XU Zhen YANG Han BAI Tianyu ZHOU Yasong WEI Qiang 《燃料化学学报(中英文)》 北大核心 2026年第2期76-87,共12页
Aiming at the problems of insufficient activity and selectivity of Cu-based catalysts in CO_(2)hydrogenation to methanol,Al_(2)O_(3),ZrO_(2)and CeO_(2)modified Cu-ZnO catalysts by the co-precipitation method were prep... Aiming at the problems of insufficient activity and selectivity of Cu-based catalysts in CO_(2)hydrogenation to methanol,Al_(2)O_(3),ZrO_(2)and CeO_(2)modified Cu-ZnO catalysts by the co-precipitation method were prepared,and the influence mechanism of additives on the structure-performance relationship of the catalysts was systematically explored.Through a variety of characterization methods such as XRD,N2 physical adsorption-desorption,TEM,H_(2)-TPR,CO_(2)-TPD and XPS,combined with catalytic performance evaluation experiments,the correlation between the microstructure of catalysts and the reaction performance of CO_(2)hydrogenation to methanol was analyzed in depth.The results show that metal additives significantly improve the performance of catalysts.After the introduction of additives,the specific surface area and pore volume of the catalysts increase,the grain size of Cu decreases,and its dispersion improves.The Ce-modified CZC catalyst exhibited the best performance,with the grain size of CuO as small as 11.41 nm,and the surface oxygen vacancy concentration(OⅡ/OⅠ=3.15)was significantly higher than that of other samples.The reaction performance test shows that under the conditions of 2.8 MPa,8000 h−1 and 280℃,the CO_(2)conversion of the CZC catalyst reached 18.83%,the methanol selectivity was 68.40%,and the methanol yield was 12.88%,all of which are superior to other catalysts.Its excellent performance can be attributed to the fact that CeO_(2)enhances the metal-support interaction,increases the surface basicity,promotes the adsorption and activation of CO_(2),and simultaneously inhibits the reverse water-gas shift side reaction.This study clarifies the structure-activity regulation mechanism of additive modification on Cu-ZnO catalysts,providing a theoretical basis and technical reference for the development of efficient catalysts for CO_(2)hydrogenation to methanol. 展开更多
关键词 carbon dioxide catalyst additive modification HYDROGENATION METHANOL
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Research on the methanation properties of biomass gasification simulation based on alkali-modified Ni/Al2O3 catalysts
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作者 XING Wanli YANG Bingjie +3 位作者 ZHANG Wanli KAI Xingping ZHOU Quan YANG Tianhua 《燃料化学学报(中英文)》 北大核心 2026年第3期71-78,共8页
In this paper,the Ni/Al_(2)O_(3) monolithic catalyst with 15%Ni content was prepared using cordierite as a matrix,and the catalyst was modified with 10%NaOH to study the methanation performance of biomass gasification... In this paper,the Ni/Al_(2)O_(3) monolithic catalyst with 15%Ni content was prepared using cordierite as a matrix,and the catalyst was modified with 10%NaOH to study the methanation performance of biomass gasification simulated gas based on alkali-modified Ni/Al_(2)O_(3) monolithic catalyst.BET,TEM,H_(2)-TPR,XRD,CO_(2)-TPD and TG were used to characterize the physicochemical properties of the catalyst before and after modification.The results indicated that the CO conversion rate trends of unmodified and modified Ni/Al_(2)O_(3) monolithic catalysts over 2 h were fundamentally consistent.However,the Ni/Al_(2)O_(3) catalysts modified for 2 h demonstrated significantly enhanced performance compared to those modified for 1 h.Regarding CH4 selectivity,the modified Ni/Al_(2)O_(3) catalyst exhibited markedly better performance than the unmodified Ni/Al_(2)O_(3) catalyst,confirming the enhanced methane performance of the alkali-modified Ni/Al_(2)O_(3) monolithic catalyst.Under optimized conditions(H_(2)/CO volume ratio of 3∶1,space velocity of 10000 mL/(g·h),and temperature of 400℃),the methanation performance of the Ni/Al_(2)O_(3) monolithic catalyst modified for 2 h reached its peak,achieving a CO conversion rate of 97%with 100%CH4 selectivity. 展开更多
关键词 biomass gasification METHANATION CORDIERITE monolithic catalyst
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Fe-based metallic glass as heterogeneous Fenton-like catalyst for azo dyes degradation:effect of inorganic anions
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作者 Ming-Jie Zhou Wen-Tao Zhang +4 位作者 Zhun Li Tao Feng Si Lan Zhen Peng Shuang-Qin Chen 《Rare Metals》 SCIE EI CAS CSCD 2023年第10期3443-3454,共12页
Metallic glasses(MGs) are promising heterogeneous catalysts in water remediation,due to their superior efficiency,selectivity,reusability and corrosion resistance.However,few works are focused on the influence of inor... Metallic glasses(MGs) are promising heterogeneous catalysts in water remediation,due to their superior efficiency,selectivity,reusability and corrosion resistance.However,few works are focused on the influence of inorganic anions that are abundant in wastewater.Herein,four common inorganic anions were added in a heterogeneous Fenton-like system(Fe-MG/H_(2)O_(2)) to study inorganic anions' influence on MGs' catalytic performance during methylene blue(MB) degradation.Evidence demonstrated that chloride ions and dihydrogen phosphate ions had an adverse effect on the catalytic performance of Fe-MG,whereas Fe-MG/H_(2)O_(2) system sustained high efficiency in the presence of sulfate ions and nitrate ions during the Fenton-like process.By studying the structure,surface morphology,and evolution of active species,it was found that inorganic anions had a significant effect on the surface morphology of Fe-MG and the generation of active species.This work will provide essential references for MGs as heterogeneous catalysts in practical applications. 展开更多
关键词 fe-based metallic glass(Fe–MG) Inorganic anion Wastewater treatment Methylene blue(MB)
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Research progress on the kinetics of methane-carbon dioxide reforming catalyzed by nickel-based catalysts
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作者 HU Jingtao WU Jie +2 位作者 DENG Bangqiang LIU Dawei XU Long 《燃料化学学报(中英文)》 北大核心 2026年第2期21-45,共25页
Under the backdrop of“Carbon Peak and Carbon Neutrality”(dual carbon)goal in China,the methane-carbon dioxide reforming reaction has attracted considerable attention due to its environmental benefits of converting t... Under the backdrop of“Carbon Peak and Carbon Neutrality”(dual carbon)goal in China,the methane-carbon dioxide reforming reaction has attracted considerable attention due to its environmental benefits of converting two greenhouse gases(methane and carbon dioxide)into syngas and its promising industrial applications.Nickel(Ni)-based catalysts,with high catalytic activity,low cost,and abundant resources,are considered ideal candidates for industrial applications.In this article,three reaction kinetic models were briefly introduced,namely the Power-Law(PL)model,the Eley-Rideal(ER)model,and the Langmuir-Hinshelwood-Hougen-Watson(LHHW)model.Based on the LHHW model,the reaction kinetics and mechanisms of different catalytic systems were systematically discussed,including the properties of supports,the doping of noble metals and transition metals,the role of promoters,and the influence of the geometric and electronic structures of Ni on the reaction mechanism.Furthermore,the kinetics of carbon deposition and elimination on various catalysts were analyzed.Based on the reaction rate expressions for carbon elimination,the reasons for the high activity of transition metal iron(Fe)-doped catalysts and core-shell structured catalysts in carbon elimination were explained.Based on the detailed collation and comparative analysis of the reaction mechanisms and kinetic characteristics across diverse Ni-based catalytic systems,a theoretical guidance for the designing of high-performance catalysts was provided in this work. 展开更多
关键词 carbon dioxide reforming of methane catalyst model KINETICS carbon deposit
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