期刊文献+
任意字段
题名或关键词
题名
关键词
摘要
作者
第一作者
机构
刊名
分类号
参考文献
作者简介
基金资助
栏目信息
共找到158篇文章
< 1 2 … 8 >
每页显示 20 50 100
已选0条
引用分析
参考文献
引证文献
 统计分析
检索结果
已选文献
显示方式：
Effect of active oxygen on the performance of Pt/CeO2 catalysts for CO oxidation 认领 引用 被引量：19
1
作者 Anbin Zhou Jun Wang +3 位作者 Hui Wang Hang Li Jianqiang Wang Meiqing Shen 《Journal of Rare Earths》 SCIE EI CAS CSCD 2018年第3期257-264,共8页
This study was focused on the influence of active oxygen on the performance of Pt/CeO2 catalysts for CO oxidation. A series of CeO2 supports with different contents of active oxygen were obtained by adding surfactant ... This study was focused on the influence of active oxygen on the performance of Pt/CeO2 catalysts for CO oxidation. A series of CeO2 supports with different contents of active oxygen were obtained by adding surfactant at different synthesis steps. 0.25 wt% Pt was loaded on these CeO2 supports by incipientwetness impregnation methods. The catalysts were characterized by N2 adsorption, X-ray diffraction（XRD）, high-resolution transmission electron microscopy（HRTEM）, H2 temperature-programmed reduction（H2-TPR）, dynamic oxygen storage capacity（DOSC） and in-situ DRIFTS technologies. For S-f supports, the surfactant was added into the solution before spray-drying in the synthesis process, which facilitates more active oxygen formation on the surface of CeO2. After loading Pt, the more active oxygen on CeO2 contributes to dispersing Pt species and enhancing the CO oxidation activity. As for the aged samples,Pt-R-h shows the highest activity above 190 ℃ because of the presence of more partly oxidized Pt^（δ＋） species. Thus the activity is also influenced by the states of Pt and the Pt^（δ＋） species may contribute to the high activity at elevated temperature. 展开更多
关键词 CeO2 Active oxygen Pt/CeO2 catalyst Pt dispersion CO oxidation Rare earths
暂未订购 下载PDF
P改性Pt/CeO2单原子催化剂的CO低温氧化催化性能研究 认领 引用 被引量：1
2
作者 翟晓珊 王骞 +3 位作者 王梓林 吕岩 郭延文 丁传敏 《低碳化学与化工》 CAS 北大核心 2026年第4期31-37,共7页
CO是一种分布广泛的空气污染物,对环境和人体健康构成重大威胁。目前,CO热催化氧化被认为是最节能、最高效的转化方法,而采用传统浸渍法制备的Pt/CeO2催化剂已接近其催化性能的极限。对于负载型Pt/CeO2单原子催化剂而言,载体的表... CO是一种分布广泛的空气污染物,对环境和人体健康构成重大威胁。目前,CO热催化氧化被认为是最节能、最高效的转化方法,而采用传统浸渍法制备的Pt/CeO2催化剂已接近其催化性能的极限。对于负载型Pt/CeO2单原子催化剂而言,载体的表面性质以及金属单原子的局部配位环境对其催化性能有重要影响。通过浸渍法引入磷酸制备了P改性单原子催化剂Pt/CeO2-yPOx,利用XRD、CO-DRIFTS和FT-IR等方法对催化剂的结构进行了表征,并对其催化性能进行了研究。结果表明,当m(磷酸)/m(CeO2)≤0.0850时,Pt以单原子的形式存在于催化剂中。Pt/CeO2-yPOx中,形成了P—O—Pt配位,并且其Lewis酸量增大,也产生了微量的Brønsted酸,有利于CO吸附。同时,Pt/CeO2-yPOx的还原性能提高,所以其CO低温氧化催化性能明显提升。其中,Pt/CeO2-0.085POx催化性能最优,使得CO转化温度降低为40℃,CO转化率达到100%的温度降低为110℃。 展开更多
关键词 Pt/CeO2 CO低温氧化 P改性 单原子催化剂
暂未订购 下载PDF
Identification of relevant active sites and a mechanism study for reverse water gas shift reaction over Pt/CeO_2 catalysts 认领 引用 被引量：9
3
作者 Xiaodong Chen Xiong Su +5 位作者 Binglian Liang Xiaoli Yang Xinyi Ren Hongmin Duan Yanqiang Huang Tao Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2016年第6期1051-1057,共7页
Reverse water gas shift (RWGS) reaction can serve as a pivotal stage in the CO2 conversion processes, which is vital for the utilization of CO2. In this study, RWGS reaction was performed over Pt/CeO2 catalysts at the... Reverse water gas shift (RWGS) reaction can serve as a pivotal stage in the CO2 conversion processes, which is vital for the utilization of CO2. In this study, RWGS reaction was performed over Pt/CeO2 catalysts at the temperature range of 200-500 degrees C under ambient pressure. Compared with pure CeO2, Pt/CeO2 catalysts exhibited superior RWGS activity at lower reaction temperature. Meanwhile, the calculated TOF and E-a values are approximately the same over these Pt/CeO2 catalysts pretreated under various calcination conditions, indicating that the RWGS reaction is not affected by the morphologies of anchored Pt nanoparticles or the primary crystallinity of CeO2. TPR and XPS results indicated that the incorporation of Pt promoted the reducibility of CeO2 support and remarkably increased the content of Ce 3 + sites on the catalyst surface. Furthermore, the CO TPSR-MS signal under the condition of pure CO2 flow over Pt/CeO 2 catalyst is far lower than that under the condition of adsorbed CO2 with H-2 -assisted flow, revealing that CO2 molecules adsorbed on Ce3+ active sites have difficult in generating CO directly. Meanwhile, the adsorbed CO2 with the assistance of H-2 can form formate species easily over Ce3+ active sites and then decompose into Ce3+-CO species for CO production, which was identified by in-situ FTIR. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B. V. and Science Press. All rights reserved. 展开更多
关键词 RWGS reaction Pt/CeO2 catalyst Formate intermediate Mechanism
暂未订购 下载PDF
Grain boundary engineering of CeO2 induced electron redistribution for dimethyl carbonate synthesis from CO2 认领 引用
4
作者 Guoqiang Hou Di Xu +3 位作者 Haifeng Fan Yangyang Li Siyi Huang Mingyue Ding 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2026年第1期316-329,共14页
Direct synthesis of dimethyl carbonate(DMC)from CO2 is critical for achieving carbon neutrality,yet the sluggish formation and conversion of the key*CH₃OCOO intermediate-due to the difficulty of C-O coupling-limit ... Direct synthesis of dimethyl carbonate(DMC)from CO2 is critical for achieving carbon neutrality,yet the sluggish formation and conversion of the key*CH₃OCOO intermediate-due to the difficulty of C-O coupling-limit high DMC yields.Herein,we developed a boric acid-assisted recrystallization strategy to fabricate grain-boundary-rich CeO2 hollow nanospheres,which serve as an efficient catalyst for CO2 to DMC synthesis.The introduction of grain-boundary(GBs)induced the electron redistribution,which led a decrease in the electron density of bulk Ce ions and created a localized electron-rich region at homogeneous interface.This unique electronic landscape promoted reactive methoxy formation and stronger CO2 adsorption,thereby enabling more efficient coupling of*CH3O and*CO2 to form the*CH3OCOO.Concurrently,the enhanced CO2 adsorption facilitated the dissociation of*CH3OCOO and subsequent DMC formation.As a result,the 4%BCeO2-GBs achieved an advantageous DMC yield of 19.8 mmol/g.In the assistance of dehydrating agent,the catalyst delivered a remarkable 264.2 mmol/g DMC yield and 7.12%methanol conversion,which was 32 times higher than commercial CeO2.This study elucidated the intrinsic mechanisms governing*CH3OCOO intermediate behavior and offers valuable guidance for CO2 converting into high-value organic chemicals. 展开更多
关键词 Dimethyl carbonate synthesis CeO2 catalyst Grain boundary engineering Electron redistribution Reaction intermediates
暂未订购 下载PDF
Size-dependent strong metal-support interaction modulation of Pt/CoFe2O4 catalysts 认领 引用 被引量：1
5
作者 Yangyang Li Jingyi Yang +1 位作者 Botao Qiao Tao Zhang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2025年第2期292-302,共11页
Supported metal catalysts are the backbone of heterogeneous catalysis,playing a crucial role in the modern chemical industry.Metal-support interactions(MSIs)are known important in determining the catalytic performance... Supported metal catalysts are the backbone of heterogeneous catalysis,playing a crucial role in the modern chemical industry.Metal-support interactions(MSIs)are known important in determining the catalytic performance of supported metal catalysts.This is particularly true for single-atom catalysts(SACs)and pseudo-single-atom catalysts(pseudo-SACs),where all metal atoms are dispersed on,and interact directly with the support.Consequently,the MSI of SACs and pseudo-SACs are theoretically more sensitive to modulation compared to that of traditional nanoparticle catalysts.In this work,we experimentally demonstrated this hypothesis by an observed size-dependent MSI modulation.We fabricated CoFe2O4 supported Pt pseudo-SACs and nanoparticle catalysts,followed by a straightforward water treatment process.It was found that the covalent strong metal-support interaction(CMSI)in pseudo-SACs can be weakened,leading to a significant activity improvement in methane combustion reaction.This finding aligns with our recent observation of CoFe2O4 supported Pt SACs.By contrast,the MSI in Pt nanoparticle catalyst was barely affected by the water treatment,giving rise to almost unchanged catalytic performance.This work highlights the critical role of metal size in determining the MSI modulation,offering a novel strategy for tuning the catalytic performance of SACs and pseudo-SACs by fine-tuning their MSIs. 展开更多
关键词 Strongmetal-support interaction Single-atom catalyst Pseudo-single-atom catalyst Size dependence Pt/CoFe2O4catalyst
暂未订购 下载PDF
甲基环己烷(MCH)高效脱氢Pt/Al2O3催化剂载体性能优化及Pt的高分散机制 认领 引用 被引量：1
6
作者 苏健利 李长旭 +6 位作者 陈春明 安会丽 于峰 陈树伟 潘大海 闫晓亮 李瑞丰 《化学学报》 SCIE CAS CSCD 北大核心 2026年第1期20-29,共10页
以经溶剂限域水解-聚合法所得介孔氧化铝(MA)为载体,借助焙烧条件的调控,优化MA的晶相、织构及表面性质,提高低负载量Pt(w=0.5%)在MA孔壁表面上的分散度,继而提升所得催化剂对甲基环己烷(MCH)脱氢反应的催化性能.结果表明,经450℃焙烧后... 以经溶剂限域水解-聚合法所得介孔氧化铝(MA)为载体,借助焙烧条件的调控,优化MA的晶相、织构及表面性质,提高低负载量Pt(w=0.5%)在MA孔壁表面上的分散度,继而提升所得催化剂对甲基环己烷(MCH)脱氢反应的催化性能.结果表明,经450℃焙烧后, MA载体具有γ-Al2O3晶相和较高的比表面积,且孔壁表面存在大量与Pt前体(氯铂酸)分子强静电键合作用的Ib型Al-OH,可促使Pt以超小纳米团簇形式高度均匀分散,致使所得催化剂展现出较现有Pt基催化剂更优异的MCH脱氢催化活性.例如,在300℃低温下,催化剂Pt/MA-450显示出高达2112 mmol·gPt-1·min-1的析氢速率,且在100 h反应过程或再生循环使用过程中仍能保持80%以上的初始催化活性. 展开更多
关键词 介孔材料 甲基环己烷(MCH)脱氢 Pt/Al2O3催化剂 载体-Pt前体界面作用 铝羟基
暂未订购 下载PDF
Effects of WOx modification on the activity, adsorption and redox properties of CeO_2 catalyst for NO_x reduction with ammonia 认领 引用 被引量：26
7
作者 Ziran Ma Duan Weng +1 位作者 Xiaodong Wu Zhichun Si 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2012年第7期1305-1316,共12页
A series of WO3/CeO2 （WOx/CeO2） catalysts were synthesized by wet impregnation of ammonium metatungstate on a CeO2 support. The resulting solid acid catalysts were characterized by X-ray diffraction （XRD）, UV-Vis ... A series of WO3/CeO2 （WOx/CeO2） catalysts were synthesized by wet impregnation of ammonium metatungstate on a CeO2 support. The resulting solid acid catalysts were characterized by X-ray diffraction （XRD）, UV-Vis spectroscopy （UV-Vis）, Raman spectroscopy （Raman）, in-situ Fourier transform infrared spectroscopy （in-situ FT-IR） of ammonia adsorption, NH3-TPD, H2 temperature- programmed reduction （H2-TPR）, NH3/NO oxidation and activity measurements for NOx reduction by NH3 （NH3-SCR）. The results show that polytungstate （WOx） species are the main species of tungsten oxide on the surface of ceria. The addition of tungsten oxide enhances the BriSnsted acidity of ceria catalysts remarkably and decreases the amount of surface oxygen on celia, with strong interaction between CeO2 and WOx. As a result, the N2 selectivity of NH3 oxidation and NH3-SCR at high temperatures （〉 300℃） is enhanced. Therefore, a wide working temperature window in which NOx conversion exceeds 80% （NOx conversion 〉 80%） from 200 to 450℃, is achieved over 10 wt.% WOx/CeO2 catalyst. A tentative model of the NH3-SCR reaction route on WOx/CeO2 catalysts is presented. 展开更多
关键词 NOx reduction WOx/CeO2 catalyst redox NH3 adsorption
暂未订购 下载PDF
Effect of CeO2-ZrO2 on Pt/C electrocatalysts for alcohols oxidation 认领 引用 被引量：7
8
作者 王青春 刘振朋 +3 位作者 安胜利 王瑞芬 王艳玲 徐拓 《Journal of Rare Earths》 SCIE EI CAS CSCD 2016年第3期276-282,共7页
The electrocatalytic activity and stability of Pt/C catalyst modified by using CeO_2-ZrO_2 mixed oxides for the alcohols electrochemical oxidation as probes were investigated. The catalyst samples were characterized b... The electrocatalytic activity and stability of Pt/C catalyst modified by using CeO_2-ZrO_2 mixed oxides for the alcohols electrochemical oxidation as probes were investigated. The catalyst samples were characterized by X-ray diffraction（XRD） and scanning electron microscopy（SEM）. The electrochemical properties were measured by a three electrode system on electrochemical workstation（IVIUM）. The results showed that the presence of CeO_2-ZrO_2 might be associated with the presence of Pt, which indicated that possibly there was synergistic effect between CeO_2-ZrO_2 and Pt nanoparticles. The electrocatalytic activity and stability of Pt-MO_x/C（M=Ce, Zr） for methanol and ethanol oxidation was better than that of Pt-CeO_2/C, which was attributed to that CeO_2-ZrO_2 composited oxides enhanced oxygen mobility and promoted oxygen storage capacity（OSC）. Furthermore, the best performance was found when the molar ratio of CeO_2 to ZrO_2 was 2：1 for the oxidation of methanol and ethanol. The forward peak current density of Pt-MO_x/C（M=Ce, Zr, Ce：Zr=2：1） towards the methanol electrooxidation was about 3.8 times that of Pt-CeO_2/C. Pt-MO_x/C（M=Ce, Zr） appeared to be a promising and less expensive methanol oxidation anode catalyst. 展开更多
关键词 CeO2-ZrO2 composite oxide catalyst preparation characterization performance rare earths
暂未订购 下载PDF
Structures and reactivities of the CeO2/Pt(111)reverse catalyst:A DFT+U study 认领 引用 被引量：1
9
作者 Zhu-Yuan Zheng Dong Wang +2 位作者 Yi Zhang Fan Yang Xue-Qing Gong 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第9期1360-1368,共9页
For heterogeneous catalysts,the build-up of interface contacts can influence markedly their activities.Being different from the conventional supported metal/oxide catalysts,the reverse type of oxide/metal structures,e... For heterogeneous catalysts,the build-up of interface contacts can influence markedly their activities.Being different from the conventional supported metal/oxide catalysts,the reverse type of oxide/metal structures,e.g.the ceria/Pt composite,have emerged as novel catalytic materials in many fields.However,it remains challenging to determine the optimal interface structure and/or the metal-oxide synergistic effect that can boost catalytic activities.In this work,we conducted density functional theory calculations with on-site Coulomb interaction correction to determine the optimal structures and investigate the physical as well as catalytic properties of various Ce O2/Pt(111)composites containing Ce O2(111)monolayer,bilayer,and trilayer at Pt(111).We found that the interaction strength between Ce O2(111)and Pt(111)substrate first reduces as the ceria slab grows from monolayer to bilayer,and then largely gets converged when the trilayer occurs.Such trend was well rationalized by analyzing the number and distances of O–Pt bonds at the interface.Calculated Bader charges uncovered the significant charge redistribution occurring around the interface,whereas the net electron transfer across the interface is non-significant and decreases as ceria thickness increases.Moreover,comparative calculations on oxygen vacancy formation energies clarified that oxygen removal can be promoted on the Ce O2/Pt(111)composites,especially at the interface.We finally employed CO oxidation as a model reaction to probe the surface reactivity,and determined an intrinsic activity order of monolayer Ce O2(111)>monolayer Ce O2(111)/Pt(111)>regular Ce O2(111).More importantly,we emphasized the significant role of the moderate ceria-Pt interaction at the interface that endows the Ce O2/Pt reverse catalyst both good thermostability and high catalytic activity.The monolayer Ce O2(111)/Pt(111)composite was theoretically predicted highly efficient for catalyzing CO oxidation. 展开更多
关键词 CeO2/Pt reverse catalyst Interface structure Oxygen vacancy CO oxidation Density functional theory
暂未订购 下载PDF
CH_4-CO_2 reforming to syngas over Pt-CeO_2-ZrO_2/MgO catalysts: Modification of support using ion exchange resin method 认领 引用 被引量：1
10
作者 Min Yang Haijun Guo +1 位作者 Yansheng Li Qiong Dang 《Journal of Natural Gas Chemistry》 CSCD 2012年第1期76-82,共7页
Pt-CeO2-ZrO2/MgO （Pt-CZ/MgO） catalysts with 0.8 wt% Pt, 3.0 wt% CeO2 and 3.0 wt% ZrO2 were prepared by wet impregnation method. Support MgO was obtained using ion exchange resin method or using commercial MgO. XRD, ... Pt-CeO2-ZrO2/MgO （Pt-CZ/MgO） catalysts with 0.8 wt% Pt, 3.0 wt% CeO2 and 3.0 wt% ZrO2 were prepared by wet impregnation method. Support MgO was obtained using ion exchange resin method or using commercial MgO. XRD, BET, SEM, TEM, DTA-TG and CO2-TPD were used to characterize the catalysts. CH4-CO2 reforming to synthesis gas （syngas） was performed to test the catalytic behavior of the catalysts. The catalyst Pt-CZ/MgO-IE（D） prepared using ion exchange resin exhibits more regular structure, smaller and more unique particle sizes, and stronger basicity than the catalyst Pt-CZ/MgO prepared from commercial MgO. At 1073 K and atmospheric pressure, Pt-CZ/MgO-IE（D） catalyst has a higher activity and greater stability than Pt-CZ/MgO catalyst for CH4-CO2 reforming reaction at high gas hourly space velocity of 36000 mL/（g.h） with a stoichiometric feed of CH4 and C02. Activity measurement and characterization results demonstrate that modification of the support using ion exchange resin method can promote the surface structural property and stability, therefore enhancing the activity and stability for CH4-CO2 reforming reaction. 展开更多
关键词 Pt-CeO2-ZrO2/MgO catalyst CH4-CO2 reforming support modification stability
暂未订购 下载PDF
The sulfur and water resistance improvement of Pt/TiO2 catalyst for CO oxidation reaction by anatase and rutile TiO2 crystal interfaces 认领 引用
11
作者 Zhenxing Feng Bin Song +5 位作者 Zongcheng Zhan Lei Xu Hanlei Sun Shuo Yao Hongzhi Wang Licheng Liu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2025年第9期128-139,共12页
Catalytic oxidation is an effective strategy for eliminating CO pollutant.Pt/TiO2 catalyst are one of the most active catalysts as used,but facing the issue of sulfur and water deactivation.In this study,TiO2 wa... Catalytic oxidation is an effective strategy for eliminating CO pollutant.Pt/TiO2 catalyst are one of the most active catalysts as used,but facing the issue of sulfur and water deactivation.In this study,TiO2 was synthesized using a sol-gel method,while Pt/TiO2 was prepared by impregnation method.By varying the calcination temperature of the TiO2 support,Pt/TiO2 catalysts with different proportions of anatase and rutile phases were synthesized.At the calcination temperature of 500℃,the catalysts exhibited approximately equal proportions of anatase and rutile,resulting in exceptional catalytic activity for CO oxidation,as well as improved resistance to sulfur and water in the flue gas.Consequently,the Pt/TiO2-500 catalyst achieved a CO conversion of 93%at 160℃.Even under conditions of 8%(vol)H2O and 0.016%(vol)SO2(GHSV=300000 ml·h-1·g-1),the CO conversion remained above 95%at 220℃for 46 h.The catalysts were characterized and analyzed using various techniques.The results indicated that anatasephase TiO2 exhibited weak CO adsorption capacity but strong SO2 adsorption capacity,whereas rutilephase TiO2 demonstrated strong CO adsorption capacity and weak SO2 adsorption capacity.The presence of the anatase phase mitigated the CO self-poisoning phenomenon of the catalyst,while the biphase interface reduced the adsorption and oxidation of SO2 on the catalyst's surface,significantly inhibiting the deposition of TiOSO_4.Consequently,the Pt/TiO2-500 catalyst displayed the highest CO catalytic activity along with superior resistance to sulfur and water. 展开更多
关键词 CO oxidation Pt/TiO2catalysts TiO2support Crystal phase Sulfur tolerance
暂未订购 下载PDF
Critical role of CoO modification on Pt/Al2O3for efficient H18-DBT dehydrogenation in LOHC systems 认领 引用
12
作者 Ligang Zhang Rudong Liu +5 位作者 Chang Xu Chuanze Feng Sicong Qiu Nian Lei Kuo Liu Tao Zhang 《ENGINEERING Chemical Engineering》 SCIE EI CAS CSCD 2026年第6期37-47,共11页
Liquid organic hydrogen carriers(LOHCs)represent a highly promising strategy for hydrogen storage and long-distance transport,offering a safe and economically viable solution to key infrastructure challenges.The effec... Liquid organic hydrogen carriers(LOHCs)represent a highly promising strategy for hydrogen storage and long-distance transport,offering a safe and economically viable solution to key infrastructure challenges.The effective application of LOHCs requires dehydrogenation catalysts that strike an optimal balance between activity and stability.Herein,we report a precisely engineered CoOx-modified Pt/Al2O3catalytic system that exhibits outstanding performance in the dehydrogenation of perhydro-dibenzyltoluene(H18-DBT).Systematic investigations identify a critical CoOx loading threshold at 1 wt%,at which the catalyst achieves a maximum dehydrogenation degree(DoD)of 93%and a H2 production rate of 20.98×10³molH,molpt-1h-1 at 300°C for dehydrogenation,outperforming all the catalysts reported in the literature.However,increasing the Co loading from 1 to 10 wt%results in a sharp decline in DoD from 93%to 7.2%.With the increasing CoOx content,the cobalt species initially form amorphous CoO clusters,which subsequently transform into crystalline Co3O4.The amorphous CoO is found to be the key species responsible for enhanced dehydrogenation activity by increasing the electron density and reducing the particle size of Pt,thereby promoting dehydrogenation while suppressing the hydrogenation capability. 展开更多
关键词 LOHCs DBT CoO Pt based-bimetallic catalyst H2 storage
暂未订购 下载PDF
Boosting the water gas shift reaction on Pt/CeO2-based nanocatalysts by compositional modification: Support doping versus bimetallic alloying 认领 引用 被引量：6
13
作者 Kun Yuan Xiao-Chen Sun +4 位作者 Hai-Jing Yin Liang Zhou Hai-Chao Liu Chun-Hua Yan Ya-Wen Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第4期241-249,共9页
The water gas shift reaction is of vital significance for the generation and transition of energy due to the application in hydrogen production and industries such as ammonia synthesis and fuel cells.The influence of ... The water gas shift reaction is of vital significance for the generation and transition of energy due to the application in hydrogen production and industries such as ammonia synthesis and fuel cells.The influence of support doping and bimetallic alloying on the catalytic performance of Pt/Ce O2-based nanocatalysts in water gas shift reaction was reported in this work.Various lanthanide ions and 3d transition metals were respectively introduced into the Ce O2support or Pt to form Pt/Ce O2:Ln(Ln=La,Nd,Gd,Tb,Yb)and Pt M/Ce O2(M=Fe,Co,Ni)nanocatalysts.The sample of Pt/Ce O2:Tb showed the highest activity(TOF at 200℃=0.051 s-1)among the Pt/Ce O2:Ln and the undoped Pt/Ce O2catalysts.Besides,the sample of Pt Fe/Ce O2exhibited the highest activity(TOF at 200℃=0.12 s-1)among Pt M/Ce O2catalysts.The results of the multiple characterizations indicated that the catalytic activity of Pt/Ce O2:Ln catalysts was closely correlated with the amount of oxygen vacancies in doped ceria support.However,the different activity of Pt M/Ce O2bimetallic catalysts was owing to the various Pt oxidation states of the bimetals dispersed on ceria.The study of the reaction pathway indicated that both the samples of Pt/Ce O2and Pt/Ce O2:Tb catalyzed the reaction through the formate pathway,and the enhanced activity of the latter derived from the increased concentration of oxygen vacancies along with promoted water dissociation.As for the sample of Pt Fe/Ce O2,its catalytic mechanism was the carboxyl route with a higher reaction rate due to the moderate valence of Pt along with improved CO activation. 展开更多
关键词 Pt/CeO2catalysts Water–gas shift reaction Support doping Bimetallic alloying
暂未订购 下载PDF
Pt-Sn-K/Al2O3催化剂催化C5~C7烷烃转化为烯烃和芳烃的反应规律 认领 引用 被引量：1
14
作者 刘昌呈 陶劲文 +2 位作者 向彦娟 王杰广 马爱增 《石油学报（石油加工）》 EI CAS CSCD 北大核心 2025年第4期1023-1033,共11页
采用浸渍法制备Pt-Sn-K/Al2O3催化剂,用盐酸作竞争吸附剂控制Pt在载体径向上的分布,采用N2吸附-脱附、XRD、STEM和电子探针微区分析(EPMA)线分析对催化剂进行表征,考察Pt分布对Pt-Sn-K/Al2O3催化剂催化正己烷脱氢反应性... 采用浸渍法制备Pt-Sn-K/Al2O3催化剂,用盐酸作竞争吸附剂控制Pt在载体径向上的分布,采用N2吸附-脱附、XRD、STEM和电子探针微区分析(EPMA)线分析对催化剂进行表征,考察Pt分布对Pt-Sn-K/Al2O3催化剂催化正己烷脱氢反应性能的影响。结果表明:加入竞争吸附剂盐酸对催化剂载体结构没有明显影响,但对Pt沿径向分布有重要影响;加入质量分数1%盐酸制备的Pt(1)-Sn-K/Al2O3催化剂中Pt均匀分布,脱氢能垒最低,反应活性最高;在反应温度为530℃、反应压力为0.07 MPa、氢气/正己烷摩尔比为1、反应时间为2 h的条件下进行Pt(1)-Sn-K/Al2O3催化正己烷脱氢反应,正己烷转化率达到50.0%,C6烯烃和苯的总选择性达到82.0%。反应温度对C5~C7烷烃在Pt(1)-Sn-K/Al2O3催化剂上的脱氢反应有重要影响,随着反应温度的升高,原料烷烃转化率逐渐增大,以C6、C7直链烷烃为原料时芳烃产率显著增加,以异构烷烃为原料时反应产物以同碳数烯烃为主。 展开更多
关键词 Pt-Sn-K/Al2O3催化剂 Pt分布 烷烃 烯烃 芳烃 脱氢反应 竞争吸附剂
暂未订购 下载PDF
Pt/Cd-TiO2选择性催化CO2加氢反应的性能 认领 引用 被引量：1
15
作者 张明文 周杰 王兆宇 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2025年第9期95-103,共9页
CO2加氢过程中间体CO在分子水平上的吸附/脱附行为会显著影响产物选择性.本文采用浸渍法制备了Pt/Cd-TiO2催化剂.通过X射线衍射(XRD)、H2气程序升温还原(H2-TPR)、拉曼光谱(Raman)、电子顺磁共振波谱(ESR)、透射电子显微镜(... CO2加氢过程中间体CO在分子水平上的吸附/脱附行为会显著影响产物选择性.本文采用浸渍法制备了Pt/Cd-TiO2催化剂.通过X射线衍射(XRD)、H2气程序升温还原(H2-TPR)、拉曼光谱(Raman)、电子顺磁共振波谱(ESR)、透射电子显微镜(TEM)、X射线光电子能谱(XPS)、CO2程序升温脱附(CO2-TPD)和N2气吸附-脱附实验等表征手段对Pt/Cd-TiO2催化剂进行表征,并将其应用于CO2加氢反应中.活性测试结果显示,Pt/TiO2加氢产物中CO选择性是87.5%,CH4选择性是12.5%.随着Cd2+的引入,Pt/Cd-TiO2的加氢产物中CO选择性提升至98.1%,CH4选择性降低至1.9%.以Pt/Cd-TiO2为催化剂,CO的生成温度降低至225℃(Pt/TiO2是250℃).原位傅里叶变换红外光谱(FTIR)和X射线光电子能谱(XPS)分析结果表明,Cd2+的引入能够降低Pt纳米颗粒(Pt NPs)表面的电子密度,Pt NPs表面电子密度的降低有利于吸附态CO(COads)脱附生成气态CO,同时抑制COads加氢生成CH4.在CO甲烷化实验中,Cd2+的引入使CH4产量降低了约6.6倍,证明Cd2+抑制了CO甲烷化生成CH4,这与Pt/Cd-TiO2在CO2加氢中CO选择性提升的结果一致.通过多种阳离子(Cd2+,Mn2+,Ba2+,K+,Na+)对Pt/TiO2进行修饰,均能提升CO选择性,其中Pt/Cd-TiO2表现出最高的CO选择性. 展开更多
关键词 二氧化碳加氢 Pt/Cd-TiO2催化剂 电子密度 一氧化碳选择性 一氧化碳吸附
暂未订购 下载PDF
不同Pt前体制备Pt/CeO2催化剂对其结构及性能的影响 认领 引用 被引量：3
16
作者 席康 王勇 +4 位作者 谢晶 王宁 周瑛 朱秋莲 卢晗锋 《化工学报》 EI CSCD 北大核心 2019年第11期4278-4288,F0002,共11页
Pt与载体间的相互作用会影响到本征Pt纳米粒子的催化活性,不同Pt前体制备Pt/CeO2催化剂会使其表现出完全不同的催化性能。分别采用金属胶体粒子原位沉积法、浸渍法以及浸渍还原的方式制备了Pt/CeO2催化剂,通过X射线衍射、程序升温还原、... Pt与载体间的相互作用会影响到本征Pt纳米粒子的催化活性,不同Pt前体制备Pt/CeO2催化剂会使其表现出完全不同的催化性能。分别采用金属胶体粒子原位沉积法、浸渍法以及浸渍还原的方式制备了Pt/CeO2催化剂,通过X射线衍射、程序升温还原、X射线光电子能谱以及高分辨透射电镜对催化剂进行表征,在CO氧化以及甲苯燃烧反应中评价催化剂活性。结果表明,胶体粒子原位沉积法制备Pt/CeO2催化剂,能够将优先合成好的Pt纳米粒子直接以金属态Pt0的形式负载到载体表面,且保证其高度均匀分散,丰富的表面Pt0很好地充当了CO、甲苯反应时的活化位点,催化剂表现出优异的性能;浸渍还原法中,Pt纳米粒子之间会发生团聚现象,同时部分Pt又以Pt^2+的形式与CeO2之间形成了Pt-O-Ce相互作用,载体表面暴露Pt0含量的下降是催化剂表现出较弱活性的主要原因;浸渍法中,以Pt离子对Pt进行负载,Pt完全以Pt^2+的形式参与到Pt-O-Ce键成键中,表面Pt0缺失,催化剂表现出明显的失活现象。Pt/CeO2催化剂中,起主要活性作用的是金属态Pt0,胶体粒子原位沉积法能够实现Pt0的直接负载,对于提高Pt基催化剂中Pt的利用率,降低Pt资源消耗都具有重要意义。 展开更多
关键词 Pt/CeO2催化剂 Pt纳米粒子 CO氧化 浸渍法 胶体沉积
暂未订购 下载PDF
Catalytic Oxidative Properties and Characterization of CuO/CeO_2 Catalysts 认领 引用 被引量：8
17
作者 蒋晓原 周仁贤 +2 位作者 袁骏 吕光烈 郑小明 《Journal of Rare Earths》 SCIE EI CAS 2003年第1期55-59,共5页
The oxidative properties and characterization of CuO, CeO 2 and CuO/CeO 2 cata lysts were examined by means of a CO micro-reactor GC system, TPR, XPS and X-r ay diffraction Rietveld methods. The results show that eith... The oxidative properties and characterization of CuO, CeO 2 and CuO/CeO 2 cata lysts were examined by means of a CO micro-reactor GC system, TPR, XPS and X-r ay diffraction Rietveld methods. The results show that either CuO or CeO 2 ac tivity is quite low for CO oxidation. However, when CuO and CeO 2 are mixed, the oxidative activity of the catalyst increases significantly, probably owing to the valency status of copper species (Cu 2+ and Cu+) on the CeO 2 surfa ce, the dispersion and reducibility. XPS surface analysis shows that CuO loading is very important in forming of either Cu 2+ or Cu+. Rietveld analysis s hows that some CuO, which has smaller ion radius than Ce 4+, enters the Ce O 2 lattice after CuO and CeO 2 are mixed. When the CuO loading reaches 5.0%, the size of CuO crystals is a minimum (6.1 nm) and the micro-strain value i s a maximum (2.86×10 -3), resulting in high surface energy and the best ac tivity for CO oxidation. 展开更多
关键词 physical chemistry CuO/CeO 2 catalysts CO micro-reactor GC system rare earths
暂未订购 下载PDF
Promoting effect of microwave irradiation on CeO2-TiO2 catalyst for selective catalytic reduction of NO by NH3 认领 引用 被引量：20
18
作者 Jie Cheng Liyun Song +5 位作者 Rui Wu Shining Li Yanming Sun Hongtai Zhu Wenge Qiu Hong He 《Journal of Rare Earths》 SCIE EI CAS CSCD 2020年第1期59-69,共11页
In this work we prepared several CeO2-TiO2 catalysts for the NH3-SCR reactionusing co-precipitation with assistance of microwave irradiation.The catalytic NH3-SCR activities over CeO2-TiO2 catalysts at low temperature... In this work we prepared several CeO2-TiO2 catalysts for the NH3-SCR reactionusing co-precipitation with assistance of microwave irradiation.The catalytic NH3-SCR activities over CeO2-TiO2 catalysts at low temperatures are largely enhanced by the treatment of microwave irradiation,the operation temperature window is also broadened.For better understanding the promotion mechanism,the catalyst prepared by conventional co-precipitation with and without microwave irradiation treatment was characterized with H2-TPR,NH3-TPD,XPS,XRD and BET.Microwave irradiation treatment accelerates the crystallite rate of CeO2-TiO2 catalysts,and greatly enlarges their surface area by adjusting their microstructures.The resistance to SO2 and H2O is also improved via regulating the hierarchical pore structure by the microwave irradiation.Microwave irradiation treatment can also improve the redox property and increase the acid sites over the catalyst surfaces.The result of in situ DRIFTS suggests that the microwave irradiation treatment generates more Br?nsted acid sites on CeO2-TiO2-2 h catalyst,helpful in SCR reactions.XPS results show that after microwave irradiation on the CeO2-TiO2 catalysts,the surface demonstrates an elevated concentration of chemisorbed oxygen,consequently leading to better oxidation of NO to NO2.Additionally,the molar ratio of Ce3+/Ce4+has been elevated after being treated by microwave irradiation,a vital factor in enhancing the NH3-SCR activities. 展开更多
关键词 SCR catalyst NH3-SCR Low temperature CeO2-TiO2 Microwave irradiation Rare earths
暂未订购 下载PDF
From nanoparticles to single atoms for Pt/CeO2:Synthetic strategies,characterizations and applications 认领 引用 被引量：16
19
作者 Ying Xin Nana Zhang +3 位作者 Yanan Lv Jin Wang Qian Li Zhaoliang Zhang 《Journal of Rare Earths》 SCIE EI CAS CSCD 2020年第8期850-862,I0002,共13页
Pt/CeO2 catalysts with unitary Pt species,nanoparticles,clusters or single atoms,often exhibit excellent activity and unique selectivity in many catalytic reactions benefiting from their small size,abundant unsaturate... Pt/CeO2 catalysts with unitary Pt species,nanoparticles,clusters or single atoms,often exhibit excellent activity and unique selectivity in many catalytic reactions benefiting from their small size,abundant unsaturated active sites,and unique electro nic structure.In recent years,a tre mendous number of related articles have provided great inspiration to future research and development of Pt/CeO2 catalysts.In this review,the state-of-the-art evolution of Pt nanoparticles to Pt single atoms on CeO2 is reviewed with the emphasis on synthetic strategies,advanced characterization techniques(allowing one to clarify the single atoms from clusters),the catalytic applications and mechanisms from the viewpoint of theoretical calculation.Finally,the critical outlooks and the challenges faced in developing the single-atom Pt/CeO2 catalysts are highlighted. 展开更多
关键词 Pt/CeO2 Single atoms Cluster Synthetic strategy Characterization Application
暂未订购 下载PDF
Influence of preparation methods on the physicochemical properties and catalytic performance of MnO_x-CeO_2 catalysts for NH_3-SCR at low temperature 认领 引用 被引量：59
20
作者 Xiaojiang Yao Kaili Ma +4 位作者 Weixin Zou Shenggui He Jibin An Fumo Yang Lin Dong 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2017年第1期146-159,共14页
This work examines the influence of preparation methods on the physicochemical properties and catalytic performance of MnOx‐CeO2 catalysts for selective catalytic reduction of NO by NH3 (NH3‐SCR) at low temperature.... This work examines the influence of preparation methods on the physicochemical properties and catalytic performance of MnOx‐CeO2 catalysts for selective catalytic reduction of NO by NH3 (NH3‐SCR) at low temperature. Five different methods, namely, mechanical mixing, impregnation,hydrothermal treatment, co‐precipitation, and a sol‐gel technique, were used to synthesizeMnOx‐CeO2 catalysts. The catalysts were characterized in detail, and an NH3‐SCR model reaction waschosen to evaluate the catalytic performance. The results showed that the preparation methodsaffected the catalytic performance in the order: hydrothermal treatment > sol‐gel > co‐precipitation> impregnation > mechanical mixing. This order correlated with the surface Ce3+ and Mn4+ content,oxygen vacancies and surface adsorbed oxygen species concentration, and the amount of acidic sitesand acidic strength. This trend is related to redox interactions between MnOx and CeO2. The catalystformed by a hydrothermal treatment exhibited excellent physicochemical properties, optimal catalyticperformance, and good H2O resistance in NH3‐SCR reaction. This was attributed to incorporationof Mnn+ into the CeO2 lattice to form a uniform ceria‐based solid solution (containing Mn‐O‐Cestructures). Strengthening of the electronic interactions between MnOx and CeO2, driven by thehigh‐temperature and high‐pressure conditions during the hydrothermal treatment also improved the catalyst characteristics. Thus, the hydrothermal treatment method is an efficient and environment‐friendly route to synthesizing low‐temperature denitrification (deNOx) catalysts. 展开更多
关键词 MnOx‐CeO2 catalyst Preparation method Nitrogen oxides Low‐temperature NH3‐SCR Electron interaction Surface acidity
暂未订购 下载PDF
已选0条
引用分析
参考文献
引证文献
 统计分析
检索结果
已选文献
上一页 1 2 … 8 下一页 到第 页
在线咨询 使用帮助 返回顶部 意见反馈