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Highly performed platinum nanosheets synthesized under in situ reaction conditions for hydrogen generation

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Journal of Energy Chemistry 2020年第12期29卷 272-279页

作者： Xiaobing Bao Yutong Gong Xiaozhong Zheng Jiayi Chen shanjun mao Yong Wang Advanced Materials and Catalysis Group Institute of CatalysisZhejiang UniversityHangzhou 310028ZhejiangChina

Surface properties of a catalyst, especially exposed crystal facets and coordination states, directly affect the catalyst's performance. Herein, we illustrate how reaction conditions direct the fabrication of a wellbehaved catalyst with desired structures in the case of hydrogen evolution reaction(HER). Stable adsorbed PtClxions on CNTs are in situ electrochemically reduced into a unique Pt nanosheet structure enclosed by high-index(311) and low-index(200) and(111) facets during HER process. Experimental results and density functional theory(DFT) calculation disclose the function mechanism between these unique structures and reactants. The adsorbed H2 O and reactive species act as capping agents protecting the(311) facet where the dissociation of water molecule is promoted, and the produced H*intermediates favorably combine and release on the nearby low-index Pt sites. The joint collaborations of these active sites afford Pt nanosheets comparable activity to 20 wt% Pt/C and a 12.7-fold over mass activity. These findings provide novel insight into the synthesis of heterogeneous catalysts with high specificity.

关键词： Pt nanosheet Crystal growth Reaction condition Hydrogen evolution Heterogeneous catalysis

Boosting the Performance Gain of Ru/C for Hydrogen Evolution Reaction Via Surface Engineering

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Energy & Environmental Materials 2023年第5期6卷 415-424页

作者： Xiaobing Bao Yuzhuo Chen shanjun mao Yong Wang Yong Yang Yutong Gong State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi'an 710072China Advanced Materials and Catalysis Group Institute of CatalysisDepartment of ChemistryZhejiang UniversityHangzhou 310028China

The surface properties of catalysts determine the intrinsic activity and *** is regarded as a potential candidate to substitute platinum for water electrolysis due to the low cost and analogous electronic structures while it suffers from severe dissolution and stability ***,the modification of Ru/C with atomically dispersed cobalt atoms is achieved via a simple thermal doping *** newly formed amorphous shell with Ru-Co sites on the Ru/C catalyst improved the hydrogen evolution reaction activity and stability ***,the obtained Co1Ru@Ru/CN_(x)catalyst exhibited an overpotential as low as 30 mV at 10 mA cm^(-2)in an alkaline medium,which is among the best HER catalysts reported so *** oxygen oxophile Co prevents the fast oxidation and dissolution of Ru species,ensuring outstanding long-term durability up to 70 *** calculations reveal that the Ru-Co coordination acts as a more active site for water dissociation than the ***,the"Ru-Co shell/Ru core"structures show high adaptability for the reaction *** simple doping strategy offers prospects for scalable preparation of highly active electrocatalysts.

关键词： high performance hydrogen evolution reaction ruthenium catalyst surface engineering

Fundamental aspects of alkyne semi-hydrogenation over heterogeneous catalysts

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Nano Research 2022年第12期15卷 10044-10062页

作者： Zhe Wang Qian Luo shanjun mao Chunpeng Wang Jinqi Xiong Zhirong Chen Yong Wang Advanced Materials and Catalysis Group Center of Chemistry for Frontier TechnologiesState Key Laboratory of Clean Energy UtilizationInstitute of CatalysisDepartment of ChemistryZhejiang UniversityHangzhou310028China College of Chemical and Biological Engineering Zhejiang UniversityHangzhou310028China

Alkyne semi-hydrogenation is extremely significant for the production of polymer-grade ethylene and lots of fine chemicals in modem *** efforts had been devoted to regulate the electronic and geometric structure of active ensembles for suppressing side reactions,including over-hydrogenation and *** strategies,such as alloying,surface decoration,atomization of metal centers,and others,were developed to promote the selective production of target alkenes in alkyne *** this review,the basic principles within reaction mechanisms and catalyst optimization would be discussed in *** an updated perspective to the fabrication of next-generation catalysts for alkyne semi-hydrogenation is also provided.

关键词： heterogeneous catalysis alkyne semi-hydrogenation metal-based catalysts catalytic mechanism

into the Role of Additives in Catalytic Synthesis of Insight Cyclohexylamine from Nitrobenzene

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Chinese Journal of Chemistry 2018年第12期36卷 1191-1196页

作者： Xuefeng Li Zhe Wang shanjun mao Yiqing chen Minghui Tang Haoran Li Yong Wang Advanced Materials and Catalysis Group Institute of CatalysisZhejiang UniversityHangzhouZhejiang 310028China

Cyclohexylamine is a versatile intermediate in various chemical industries, which can be expediently synthesized via hydrogenation of aniline or nitrobenzene. However, such processes always suffer from side reactions. Many reports have found that specific additives can suppress the formation of side products, but the mechanism is still not clear. In this work, results suggest that it is the hydroxide ion of alkali metal hydroxides, rather than the cations, which plays a key role in suppressing the side reactions on supported Ru‐based catalysts. With the assistance of LiOH, the selectivity toward cyclohexylamine increased from 85.4% to 100%. Side products, such as dicyclohexylamine, cyclohexanol and N ‐isopropyl cyclohexylamine, could no longer be detected. Theoretical calculations further disclosed that addition of alkali metal hydroxides inhibited the dissociation of enamine and decreased the adsorption energy of cyclohexylamine, which might be the reasons for a better selectivity. However, the addition of alkali metal hydroxides reduced the activity of nitrobenzene hydrogenation by unfolding the condensation reaction route. To recover or even further enhance the catalytic performance, a second metal component was introduced and the resultant RuNi/AC exhibited a significant improvement in activity compared with Ru/AC.

关键词： cyclohexylamine nitrobenzene hydrogenation heterogeneous catalysis basicity bimetallic catalysts

Selective Electrochemical Reduction of Nitrogen to Ammonia by Adjusting the Three-Phase Interface

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Research 2019年第1期2019卷 66-77页

作者： Haiyan Wang Yuzhuo Chen Ruxue Fan Jiadong Chen Zhe Wang shanjun mao Yong Wang Advanced Materials and Catalysis Group Institute of CatalysisDepartment of ChemistryZhejiang UniversityHangzhou 310028China

The electrochemical nitrogen reduction reaction(NRR)provides a sustainable and alternative avenue to the Haber-Bosch process for ammonia(NH_(3))*** the great efforts made on catalysts and electrolytes,unfortunately,current NRR suffers from low selectivity due to the overwhelming competition with the hydrogen evolution reaction(HER).Here,we present an adjusted three-phase interface to enhance nitrogen(N_(2))coverage on a catalyst surface and achieve a record-high Faradic efficiency(FE)up to 97%in aqueous *** almost entirely suppressed HER process combined with the enhanced NRR activity,benefiting from the efficient three-interface contact line,is responsible for the excellent selectivity toward NH_(3),as evidenced by the theoretical and experimental *** strategy also demonstrates the applicability to other catalysts that feature strong H adsorption ability,to boost the FE for NH_(3) synthesis above 90%and to improve the NRR activity by engineering the catalysts.

关键词： synthesis solution selectivity

Cooperative Assembly of Asymmetric Carbonaceous Bivalve-Like Superstructures from Multiple Building Blocks

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Research 2018年第1期2018卷 44-53页

作者： Lei Xie Haiyan Wang Chunhong Chen shanjun mao Yiqing Chen Haoran Li Yong Wang Advanced Materials and Catalysis Group Institute of CatalysisZhejiang UniversityHangzhou 310028China

Te assembly of superstructures from building blocks is of fundamental importance for engineering materials with distinct morphologies and properties,and deepening our understanding of self-assembly processes in *** to now,it is still a great challenge in materials science to construct multiple-component superstructure with unprecedented architectural complexity and symmetry from ***,we demonstrate an improved one-pot hydrothermal carbonization of biomass strategy that is capable of fabricating unprecedented asymmetric carbonaceous bivalve-like superstructures with in suit generated solid particles and ordered porous polymers as two kinds of building *** our system,diferent building blocks can be controllably generated,and they will assemble into complex superstructures through a proposed“cooperative assembly of particles and ordered porous polymers”*** believe that this assembly principle will open up new potential felds for the synthesis of superstructures with diverse morphologies,compositions,and properties.

关键词： properties. mechanism symmetry

Towards the selectivity distinction of phenol hydrogenation on noble metal catalysts

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Nano Materials Science 2023年第1期5卷 91-100页

作者： shanjun mao Zhe Wang Zhirong Chen Kejun Wu Kaichao Zhang Qichuan Li Huihuan Yan Guofeng Lü Guodong Huang Yong Wang Advanced Materials and Catalysis Group Institute of CatalysisDepartment of ChemistryZhejiang UniversityHangzhou310028PR China College of Chemical and Biological Engineering Zhejiang UniversityHangzhou310027PR China Zhejiang NHU Company Ltd Xinchang CountyZhejiang ProvincePR China

Selective hydrogenation of phenol to cyclohexanone is intriguing in chemical *** a few catalysts with promising performances have been developed in recent years,the basic principle for catalyst design is still missing owing to the unclear catalytic *** work tries to unravel the mechanism of phenol hydro-genation and the reasons causing the selectivity discrepancy on noble metal catalysts under mild *** show that different reaction pathways always firstly converge to the formation of cyclohexanone under mild *** selectivity discrepancy mainly depends on the activity for cyclohexanone sequential hy-drogenation,in which two factors are found to be responsible,*** hydrogenation energy barrier and the competitive chemisorption between phenol and cyclohexanone,if the specific co-catalyzing effect of H 2 O on Ru is not *** on the above results,a quantitative descriptor,E b(one/pl)/E a,in which E a can be further correlated to the d band center of the noble metal catalyst,is proposed by the first time to roughly evaluate and predict the selectivity to cyclohexanone for catalyst screening.

关键词： Phenol Selective hydrogenation Cyclohexanone DFT Noble metal catalysts

Rational design of hydrogenation catalysts using nitrogen-doped porous carbon

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Chinese Journal of Catalysis 2019年第7期40卷 971-979页

作者： Yuzhuo Chen Zhe Wang shanjun mao Yong Wang 浙江大学催化研究所先进材料与催化课题组浙江杭州310028

1. Introduction Hydrogenation is one of the most important reactions in the chemical and petroleum refining industries. Since Sabatier [1] first studied the hydrogenation of unsaturated organic compounds in the presence of nickel in 1897, different catalysts have been tested for the hydrogenation of a wide range of substances to produce useful chemicals or intermediates. Compared with homogeneous catalysts, heterogeneous catalysts have attracted greater attention due to their easier separation and better handling properties [2]. Among the various heterogeneous catalysts, metal-supported catalysts are widely used in various hydrogenation reactions. Particularly, metal oxides are generally used as supports in consecutive hydrogenation reactions due to their high mechanical strength, whereas carbon supports are often utilized to produce fine medicals owing to their large surface area and acid-alkali resistance.

关键词：负载型催化剂氮掺杂炭催化选择性加氢碳基催化剂化工

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煤矿地理信息系统数据模型的研究

测绘学报 1998年第4期27卷 331-337页

作者：毛善君北京大学遥感与地理信息系统研究所

地下煤矿开采所面对的空间目标具有灰色、动态变化的特征。本文在分析煤矿空间信息特点的基础上，提出了实用于煤矿的地理信息系统数据模型。这些数据模型包括全要素的结构化不规则三角网（ＴＩＮ）与ＧＩＳ一体化的数据模型以及网状模型。

关键词：煤矿数据模型不规则三角网 GIS 矿山测量