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One-pot synthesis of Pt-Cu bimetallic nanocrystals with different structures and their enhanced electrocatalytic properties

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Nano Research 2018年第5期11卷 2612-2624页

作者： daowei gao Shuna Li Guolong Song Pengfei Zha Cuncheng Li Qin Wei Yipin Lv Guozhu Chen School of Chemistry and Chemical Engineering University of Jinan Jinan 250022 China State Key Laboratory of Heavy Oil Processing China University of Petroleum Beijing 102249 China

Shape-controlled synthesis of Pt-Cu alloy nanocrystals （NCs） with unique geometries is of great importance in the rational design and deterministic synthesis of highly active electrocatalysts. Herein, Pt-Cu alloy NCs with concave octahedron （COH）, porous octahedron （POH）, yolk-shell （YSH）, and nanoflower （NOF） structures were fabricated by altering the sequential reduction kinetics in a one-pot aqueous phase. The effect of the reaction kinetics on the formation of Pt-Cu bimetallic NCs with different morphologies was analyzed quantitatively. The concentrations of glycine and metal cation are demonstrated to play a key role in the reduction of Pt（Ⅳ） and Cu（Ⅱ） ions; these significantly affected the morphology of Pt-Cu NCs. These Pt-Cu alloy NCs exhibit substantially enhanced catalytic activity and durability for methanol and formic acid oxidation compared to the commercial Pt/C catalyst. Specifically, the COH and NOF Pt-Cu NCs with more step atoms, intragranular dislocations, and protrusions showed superior electrochemical properties than those of POH and YSH Pt-Cu NCs. The structure- property relationship between the Pt-Cu NCs and their electrochemical performances was also investigated in depth.

关键词： Pt-Cu nanocrystals different structures reduction kinetics electrocatalytic properties

Defect-density control of platinum-based nanoframes with high-index facets for enhanced electrochemical properties

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Nano Research 2019年第11期12卷 2881-2888页

作者： Shaohan Yang Shuna Li Lianghao Song Yipin Lv Zhongyao Duan Chunsheng Li Raphael Francesco Praeg daowei gao Guozhu Chen School of Chemistry and Chemical Engineering University of JinanJinan250022China Institute for Solar Fuels Helmholtz Zentrum Berlin für Materialien und Energie GmbHBerlin14109Germany Young Investigator Group Operando Characterization of Solar Fuel Materials Helmholtz-Zentrum Berlin für Materialien und Energie GmbHBerlin12489Germany

Structure-engineered platinum-based nanoframes(NFs)at the atomic level can effectively improve the catalytic performance for fuel cells and other heterogeneous catalytic *** report herein,a microwave-assisted wet-chemical method for the preparation of platinum-copper-cobalt NFs with tunable defect density and architecture,which exhibit enhanced activity and durability towards the electro-oxidation reactions of methanol(MOR)and formic acid(FAOR).By altering the reduction/capping agents and thus the nucleation/growth kinetics,trimetallic platinum-copper-cobalt hexapod NFs with different density high-index facets are ***,the rough hexapod nanoframes(rh-NFs)exhibit excellent specific activities towards MOR and FAOR,7.25 and 5.20 times higher than those of benchmark Pt/C,respectively,along with prolonged *** excellent activities of the rh-NFs are assigned to a synergistic effect,including high density of defects and high-index facets,suitable d-band center,and open-framework *** synergistic working mechanism opens up a new way for enhancing their electrocatalytic performances by increasing defect density and high-index facets in open-framework platinum-based NFs.

关键词： nanoframes defect-density high-index facets electrocatalyst

Pt-confinement catalyst with dendritic hierarchical pores on excellent sulfur-resistance for hydrodesulfurization of dibenzothiophene and 4,6-dimethyldibenzothiophene

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Green Energy & Environment 2022年第2期7卷 324-333页

作者： Xilong Wang Chengkun Xiao Mohnnad H.Alabsi Peng Zheng Zhengkai Cao Jinlin Mei Yu Shi Aijun Duan daowei gao Kuo-Wei Huang Chunming Xu State Key Laboratory of Heavy Oil Processing China University of Petroleum(Beijing)Beijing102249China KAUST Catalysis Center and Division of Physical Sciences and Engineering King Abdullah University of Science and TechnologyThuwal23955-6900Saudi Arabia School of Chemistry and Chemical Engineering University of JinanJinan250022China

Metal confinement catalyst Mo S_(2)/Pt@TD-6%Ti(TD,TS-1/Dendritic mesoporous silica nanoparticles composite) in dendritic hierarchical pore structures was synthesized and showed excellent sulfur-resistance performance and stabilities in catalytic hydrodesulfurization reactions of probe sulfide *** Mo S_(2)/Pt@TD-6%Ti catalyst combines the concepts of Pt-confinement effect and hydrogen spillover of Pt noble *** modified micropores of Mo/Pt@TD-6%Ti only allow the migration and dissociation of small H_(2) molecules(0.289 nm),and effectively keep the sulfur-containing compounds(e.g.H_(2)S,0.362 nm) ***,the Mo S_(2)/Pt@TD-6%Ti catalyst exhibits higher DBT and 4,6-DMDBT HDS activities because of the synergistic effect of the strong H_(2) dissociation ability of Pt and desulfurization ability of Mo S_(2) with a lower catalyst *** new concept combining H2dissociation performance of noble metal catalyst with the desulfurization ability of transition metal sulfide Mo S_(2) can protect the noble metal catalyst avoiding deactivation and poison,and finally guarantee the higher activities for DBT and 4,6-DMDBT HDS.

关键词： catalyst sulfur pores

Morphology-selective synthesis of active and durable gold catalysts with high catalytic performance in the reduction of 4-nitrophenol

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Nano Research 2016年第10期9卷 3099-3115页

作者： daowei gao Xin Zhang Xiaoping Dai Yuchen Qin Aijun Duan Yanbing Yu Hongying Zhuo Hairui Zhao Pengfang Zhang Yan Jiang Jianmei Li Zhen Zhao State Key Laboratory of Heavy Oil Processing China University of Petroleum Beijing 102249 China College of Science China University of Petroleum Beijing 102249 China

A series of novel catalysts consisting of nanosized Au particles confined in micro-mesoporous ZSM-5/SBA-15 （ZSBA） materials with platelet （PL）, rod （RD）, and hexagonal-prism （HP） morphologies have been synthesized in situ. These catalysts possess both SBA-15 and ZSM-5 structures and exhibit excellent stability of their active sites by confinement of the Au nanoparticles （NPs） within ZSBA. The catalysts have been characterized in depth to understand their structure-property relationships. The gold NP dimensions and the pore structure of the catalysts, which were found to be sensitive to calcination temperature and synthetic conditions, are shown to play vital roles in the reduction of 4-nitrophenol. Au/ZSBA-PL, with short mesochannels （210 nm） and a large pore diameter （6.7 nm）, exhibits high catalytic performance in the reduction of 4-nitrophenol, whereas Au/ZSBA-HP and Au/ZSBA-RD, with long mesochannels and relatively smaller pore sizes, show poor catalytic activities. In the case of catalysts with different gold NP sizes, Au/ZSBA-PL-350 with an Au NP diameter of 4.0 nm exhibits the highest reaction rate constant （0.14 min-1） and turnover frequency （0.0341 s-1）. In addition, the effect of the reaction parameters on the reduction of 4-nitrophenol has been systematically investigated. A possible mechanism for 4-nitrophenol reduction over the Au/ZSBA catalysts is proposed.

关键词： gold catalysis porous material environmental pollution 4-nitrophenol

室内环境对ZigBee无线网络信号传输强度的影响

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兵工学报 2020年第S2期41卷 275-279页

作者：李鹏斐王伟刘炳楠张志永高道伟北京理工大学机电动态控制重点实验室北京100081

室内空间利用无线网络进行定位的算法中质心定位法等需要利用信号强度测距,但由于室内空间环境复杂,基于信号强度的测距模型准确性对室内无线网络定位精度影响较大。分析影响室内无线网络接收信号强度的主要因素,通过实验研究了收发终... 详细信息

室内空间利用无线网络进行定位的算法中质心定位法等需要利用信号强度测距,但由于室内空间环境复杂,基于信号强度的测距模型准确性对室内无线网络定位精度影响较大。分析影响室内无线网络接收信号强度的主要因素,通过实验研究了收发终端距地高度、天线方向、接收终端移动方向和人体遮挡4种因素对信号传输强度的影响。根据实测数据建立了典型室内无其他障碍物遮挡环境中接收信号强度随传输距离的衰减模型。研究结果表明,所建立的室内空间无其他障碍物遮挡环境信号强度衰减模型,提供了更为准确的信号强度与传输距离之间的关系。

关键词： ZigBee无线网络室内定位接收信号强度信号强度衰减模型

载体相变下Pt-TiO_(2) SMSI研究及其对CO催化性能的影响

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化学学报 2022年第9期80卷 1289-1298页

作者：贾亚辉李春生徐忠震刘伟高道伟陈国柱济南大学化学化工学院济南255022 济南大学水利与环境学院济南250002

金属-载体强相互作用(SMSI)是多相催化中的一个重要概念,对负载金属催化剂的稳定性和活性均有重要影响.目前尽管有关Pt-TiO_(2)体系的SMSI已有阐述,但主要围绕载体的结构敏感性(晶面效应)、贵金属的粒径尺寸(尺寸效应)对SMSI的影响进行... 详细信息

金属-载体强相互作用(SMSI)是多相催化中的一个重要概念,对负载金属催化剂的稳定性和活性均有重要影响.目前尽管有关Pt-TiO_(2)体系的SMSI已有阐述,但主要围绕载体的结构敏感性(晶面效应)、贵金属的粒径尺寸(尺寸效应)对SMSI的影响进行研究,而TiO_(2)的晶型对SMSI的形成是否存在影响目前尚未报道.在本工作中,选择青铜矿TiO_(2)(B)为载体,通过浸渍法负载Pt得到Pt-TiO_(2)(B)催化剂,并在H_(2)、H_(2)-O_(2)氛围对其进行热处理.研究结果表明,500℃高温下H2处理不仅导致催化剂中载体由青铜矿变为锐钛矿,而且引起载体迁移至Pt颗粒表面形成几何包覆.当此催化剂再次经400℃O_(2)处理,Pt颗粒表面的包覆层消失,呈现典型的SMSI行为.借助高分辨透射电子显微镜(HRTEM)以及CO漫反射傅立叶变换红外光谱(CO-DRIFTS)结果分析,TiO_(2)的晶型转变对SMSI的形成具有重要影响.此外,对不同气氛、温度下处理的Pt-TiO_(2)进行了催化CO氧化性能研究,结果证明SMSI产生的几何包覆以及载体的氧缺陷对催化CO氧化性能提升发挥了重要作用.显然,该工作丰富了Pt-TiO_(2)体系的SMSI研究,为其它载体晶相转变(或物相转变)可能诱导SMSI产生提供了参考意义.

关键词：金属-载体强相互作用青铜矿晶相转变几何包覆 CO氧化

CeO_(2)表面工程与PtBi纳米板间p-d轨道杂化的协同效应在甲醇电氧化中的应用

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Science China Materials 2024年第6期67卷 1975-1984页

作者：张衍澳王帅司飞燕薛瑞昕吕一品陈国柱高道伟 School of Chemistry and Chemical Engineering University of JinanJinan 250022China

调控铂(Pt)电子结构是增强Pt基电催化剂活性和耐久性的关键策略.本研究开发了CeO_(2)/PtBi金属间纳米板(NPs),这种结构通过Pt和Bi之间的强p-d轨道杂化,显著提高了催化剂在甲醇电氧化反应(MOR)中的活性和稳定性.CeO_(2)的表面沉积不仅进... 详细信息

调控铂(Pt)电子结构是增强Pt基电催化剂活性和耐久性的关键策略.本研究开发了CeO_(2)/PtBi金属间纳米板(NPs),这种结构通过Pt和Bi之间的强p-d轨道杂化,显著提高了催化剂在甲醇电氧化反应(MOR)中的活性和稳定性.CeO_(2)的表面沉积不仅进一步优化了Pt的电子结构,还提供了额外的羟基吸附位点.特别是,在酸性和碱性环境下,CeO_(2)/PtBi NPs展现出超越商业Pt/C的甲醇电氧化质量活性,分别提高了1.62和7.65倍.在经历了1000次耐久性测试后,CeO_(2)/PtBi NPs在酸碱环境下的活性仅分别下降了20.1%和39.8%,相比之下,商业Pt/C的活性在相同条件下分别下降了55.4%和78.5%.CeO_(2)/PtBi NPs的这一卓越性能得益于Pt与Bi之间的p-d轨道杂化以及CeO_(2)表面工程对催化剂电子结构的有效调节.本研究为Pt基电催化剂设计提供了新的电子结构调控策略和深入见解.

关键词： electrocatalysis intermetallic p-d orbital hybridiza-tion CeO_(2)deposition methanol electro-oxidation

反应堆通风系统安全壳隔离阀故障期间安全壳内部压力的控制方式

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机电工程技术 2023年第1期52卷 281-285页

作者：冯志新高道微中核核电运行管理有限公司浙江嘉兴314300

重水反应堆CANDU6机组在反应堆厂房通风系统的入口安全壳隔离阀缺陷处理期间,由于安全壳内设备仪用压缩空气的持续使用,必将导致安全壳内压力持续上升,压力持续上升会闭锁应急供水系统向蒸汽发生器(SG)应急补水功能,触发安全壳隔离系统... 详细信息

重水反应堆CANDU6机组在反应堆厂房通风系统的入口安全壳隔离阀缺陷处理期间,由于安全壳内设备仪用压缩空气的持续使用,必将导致安全壳内压力持续上升,压力持续上升会闭锁应急供水系统向蒸汽发生器(SG)应急补水功能,触发安全壳隔离系统自动动作关闭安全壳隔离阀,甚至因安全壳高压力触发停堆保护系统动作,所以此时安全壳内部压力降压控制是必须考虑的首要问题。对可用于安全壳内降压的四种方式进行了详细论述,对分别使用反应堆安全壳厂房排放机、重水蒸汽回收系统的压差控制风机采用间歇运行和连续运行策略的分析论证,提出了较为合理可行的反应堆安全壳降压手段,为某核电厂重水堆今后出现类似的缺陷时,提过了科学、合理可行的安全壳内部降压方案。

关键词：安全壳安全壳隔离阀压力排风机

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FCC汽油加氢脱硫工艺技术研究进展

石油与天然气化工 2013年第3期42卷 216-221页

作者：高道伟段爱军赵震邓云川中国石油大学(北京)重质油国家重点实验室

介绍了国内外典型的选择性加氢脱硫工艺及加氢脱硫-辛烷值恢复工艺的研究进展。对各工艺的流程及特点进行比较,并概述了目前工业上常用的FCC汽油加氢脱硫催化剂。最后,对FCC汽油加氢脱硫技术的发展趋势进行了展望。

关键词：加氢脱硫辛烷值恢复催化剂研究发展趋势