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Core-shell structured Ru-Ni@SiO_2: Active for partial oxidation of methane with tunable H_2/CO ratio

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Journal of Energy Chemistry 2018年第3期27卷 883-889页

作者： Yixuan Dou Yijun Pang Lingli Gu Yifan Ding Wu Jiang Xinzhen Feng Weijie Ji chak-Tong au Key Laboratory of Mesoscopic Chemistry MOE School of Chemistry and Chemical Engineering Nanjing University Department of Chemistry Hong Kong Baptist University

This study demonstrated that a Ru-Ni bimetallic core-shell catalyst（0.6%Ru-Ni）@Si O2with a proper surface Ru concentration is superior in achieving better catalytic activity and tunable H2/CO ratio at a comparatively lower reaction temperature（700℃）.Compared to the impregnation method,the hydrothermal approach leads to a highly uniform Ru distribution throughout the core *** Ru distribution would result in a proper surface Ru concentration as well as more direct Ru-Ni interaction,accounting for better catalyst *** surface Ru species hinders surface carbon deposition,but also declines overall activity and H2/CO ratio,meanwhile likely enhances Ni oxidation to certain degree under the applied reaction *** the current（m%Ru-Ni）@Si O2catalyst,the formation of fibrous carbon species is suppressed,which accounts for good stability of catalyst within a TOS of 10 h.

关键词： Ruthenium Nicolet Bimetallic Core-shell structure Partial oxidation of methane

MODIFIED SCHEME BASED ON SEMI-ANALYTIC APPROACH FOR COMPUTING NON-PROBABILISTIC RELIABILITY INDEX

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Acta Mechanica Solida Sinica 2010年第2期23卷 115-123页

作者： Xuyong Chen chak-yin tang Chi-pong Tsui Jianping Fan Hubei Key Laboratory for Engineering Structrual Analysis and Safety Assessment School of Civil Engineering and Mechanics Huazhong University of Science and Technology Wuhan 430074 China Department of Industrial and Systems Engineering The Hong Kong Polytechnic University Hong Kong China

A new computation scheme proposed to tackle commensurate problems is devel- oped by modifying the semi-analytic approach for minimizing computational complexity. Using the proposed scheme, the limit state equations, usually referred to as the failure surface, are obtained from transformation of an interval variable to a normalized one. In order to minimize the computational cost, two algorithms for optimizing the calculation steps have been proposed. The monotonicity of the objective function can be determined from narrowing the scope of interval variables in normalized infinite space by incorporating the algorithms into the computational scheme. Two examples are used to illustrate the operation and computational efficiency of the approach. The results of these examples show that the proposed algorithms can greatly reduce the computation complexity without sacrificing the computational accuracy. The advantage of the proposed scheme can be even more efficient for analyzing sophistic structures.

关键词： semi-analytic approach non-probabilistic reliability index interval variable,state equation monotonicity

Effects of cerium and tungsten addition on acid-base properties of spindle-likeα-Fe_(2)O_(3)in low-temperature SCR of NO_(x)with NH_(3)

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Journal of Rare Earths 2022年第11期40卷 1734-1742,I0003页

作者： Jun Ni Xuanbei Peng Linlin Yang Kai Zhang Yangyu Zhang Yanliang Zhou Xiuyun Wang chak-tong au Lilong Jiang National Engineering Research Center of Chemical Fertilizer Catalyst Fuzhou UniversityFuzhou 350002China

Low-temperature selective catalytic reduction(SCR)is important for the elimination of NOfrom stationary *** the present study,the loading of Ce and W onα-Fe_(2)O_(3)was achieved through the integration of single-mode microwave and incipient wetness impregnation(IWI)*** scanning electron microscopy(SEM)and transmission electron microscopy(TEM)images reveal that the structure ofα-Fe_(2)O_(3)is spindle-like,and the structure remains unchanged after the introduction of Ce and/or *** results of NH-SCR investigation demonstrate that NOconversion over Ce-W/α-Fe_(2)O_(3)is more than85%at 300℃,which is much higher than that over Ce/a-Fe_(2)O_(3)andα-Fe_(2)O_(3),Our studies illustrate that the addition of Ce can significantly increase the amount of surface oxygen vacancies as well as sites of moderate *** the other hand,the addition of W can obviously decrease the amount of basic sites and increase the number of Br?nsted acid *** synergistic effect of Ce and W addition on balancing acidity/basicity properties accounts for the high activity of CeW/α-Fe_(2)O_(3)for NOremoval at low *** study provides insight into the relationship between acidity/basicity properties and catalytic performance of Ce-W/α-Fe_(2)O_(3)catalysts,which is beneficial to the design of high-performance NH-SCR catalyst for NOremoval at low temperatures.

关键词： NH_(3)-SCR Fe_(2)O_(3) NO_(x)removal Acidity/basicity properties Morphology structure Rare earths

Target-oriented confinement of Ru-Co nanoparticles inside N-doped carbon spheres via a benzoic acid guided process for high-efficient low-temperature ammonia synthesis

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Journal of Energy Chemistry 2021年第6期30卷 140-146,I0005页

作者： Jun Ni Zhenni Tan Qianjin Sai Jie Zhu Xiuyun Wang Bingyu Lin Jianxin Lin chak-tong au Lilong Jiang National Engineering Research Center of Chemical Fertilizer Catalyst Fuzhou UniversityFuzhou 350002FujianChina

Ru-based heterogeneous catalysts have been used in a wide range of important ***,due to the sintering of Ru nanoparticles their practical applications are somewhat ***,for the first time we report a new and facile strategy to confine Ru and/or Co nanoparticles(NPs) in the channels of N-doped carbon using benzoic acid to guide the deposition location of *** developed catalyst with confined RuCo alloy particles exhibits high resistance against Ru sintering and displays excellent activity and long term stability for NH3 synthesis,achieving an NH3 synthesis rate of up to 18.9 mmol NH_(3) gcat^(-1)h^(-1)at 400℃,which is ca.2.25 times that of the catalyst prepared without confinement(with metal deposited on the support surface).In the latter case,there is an increase of nanoparticle size from 2.52 to 4.25 nm together with ca.48% decrease of NH_(3) synthesis rate after 68 h at 400℃.This study provides a new avenue for simple fabrication of precious-metal-based catalysts that are highly resistant against sintering,specifically suitable for low-temperature synthesis of ammonia with outstanding efficiency.

关键词： Ru-and Co-based catalysts Ammonia synthesis Confinement Sintering resistance Nanoparticle size

Porous FeO_x/BiVO_(4-δ)S_(0.08): Highly efcient photocatalysts for the degradation of Methylene Blue under visible-light illumination

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Journal of Environmental Sciences 2013年第10期25卷 2138-2149页

作者： Zhenxuan Zhao Hongxing Dai Jiguang Deng Yuxi Liu Yuan Wang Xinwei Li Guangmei Bai Baozu Gao chak Tong au Laboratory of Catalysis Chemistry and Nanoscience Department of Chemistry and Chemical Engineering College of Environmental and Energy Engineering Beijing University of Technology Department of Chemistry and Center for Surface Analysis and Research Hong Kong Baptist University

Porous S-doped bismuth vanadate with an olive-like morphology and its supported iron oxide （y wt.% FeOx/BiVO4-δS0.08, y = 0.06, 0.76, and 1.40） photocatalysts were fabricated using the dodecylamine-assisted alcohol-hydrothermal and incipient wetness impregnation methods, respectively. It is shown that the y wt.% FeOx/BiVO4-δS0.08 photocatalysts contained a monoclinic scheetlite BiVO4 phase with a porous olive-like morphology, a surface area of 8.8-9.2 m^2/g, and a bandgap energy of 2.38-2.42 eV. There was co-presence of surface Bi^5＋, Bi^3＋, V^5＋, V^3＋, Fe^3＋, and Fe^2＋ species in y wt.% FeOx/BiVO4-δS0.08. The 1.40 wt.% FeOx/BiVO4-δS0.08 sample performed the best for Methylene Blue degradation under visible-light illumination. The photocatalytic mechanism was also discussed. We believe that the sulfur and FeOx co-doping, higher oxygen adspecies concentration, and lower baudgap energy were responsible for the excellent visible-light-driven catalytic activity of 1.40 wt.% FeOx/BiVO4-δS0.08.

关键词： sulfur-doped bismuth vanadate supported iron oxide visible-light-driven photocatalyst porous morphology Methylene Blue degradation

Efficient catalytic removal of COS and H_(2)S over graphitized 2D micro-meso-macroporous carbons endowed with ample nitrogen sites synthesized via mechanochemical carbonization

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Green Energy & Environment 2022年第5期7卷 983-995页

作者： Xun Kan Guanqing Zhang Yingying Luo Fujian Liu Yong Zheng Yihong Xiao Yanning Cao chak-tong au Shijing Liang Lilong Jiang National Engineering Research Center of Chemical Fertilizer Catalyst(NERC-CFC) School of Chemical EngineeringFuzhou UniversityFuzhou350002China

Developing a suitable catalyst for the elimination of highly toxic carbonyl sulfide(COS)and hydrogen sulfide(H_(2)S) is of great significance in terms of industrial safety and environmental *** demonstrate here the facile synthesis of graphitized 2D micro-meso-macroporous carbons by one-step carbonization of a mixture of urea and glucose at 700–900℃.The as-synthesized graphitized catalysts,designated as 2DNHPC-x(x=urea/glucose mass ratio),are endowed with an ultra-high concentration(12.9–20.2 wt%)of stable and versatile nitrogen sites(*** and pyridine)which are anchored on the surface via stable covalent *** a result,the 2D-NHPC-x are active in catalytic hydrolysis of COS on pyrrolic N to H_(2)S,and the H_(2)S can be subsequently captured on pyridinic N and converted to elemental sulfur at ambient conditions over the same *** the prepared catalysts,2D-NHPC-x can catalytically hydrolysize 91%of COS to H_(2)S at 30℃,whereas the conversion ratio over the common catalysts g-C_(3)N_(4)and Fe_(2)O_(3)are below 6.0%.Furthermore,these catalysts also exhibit H_(2)S conversion and sulfur selectivity of nearly 100%at 180℃with long-time durability,which is higher than those of the most reported carbonbased *** contrast,the H_(2)S capacities of activated carbon,ordered mesoporous carbons(OMC)and N-doped OMC are 3.9,1.5 and2.39 mmol g^(-1),*** the experimental and theoretical results are disclosed that 2D-NHPC-x are superior to the nitrogen-doped porous materials ever applied in simultaneous catalytic elimination of both COS and H_(2)S.

关键词： carbons catalytic endowed

Attenuation of arsenic in a karst subterranean stream and correlation with geochemical factors: A case study at Lihu,South China

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Journal of Environmental Sciences 2014年第11期26卷 2222-2230页

作者： Liankai Zhang Hui Yang Jiansheng tang Xiaoqun Qin au Yik Yu Institute of Karst Geology Chinese Academy of Geological Sciences Karst Dynamics Laboratory Ministry of Land and Resources and Guangxi Zhuang Autonomous Region

Arsenic （As） pollutants generated by human activities in karst areas flow into subterranean streams and contaminate groundwater easily because of the unique hydrogeological characteristics of karst areas. To elucidate the reaction mechanisms of arsenic in karst subterranean streams, physical-chemical analysis was conducted by an inductively coupled plasma mass spectrometer and an X-ray fluorescence spectrometer. The results show that inorganic species account for most of the total arsenic, whereas organic arsenic is not detected or occurs in infinitesimal amounts. As（III） accounts for 51.0% ± 9.9% of the total inorganic arsenic. Arsenic attenuation occurs and the attenuation rates of total As, As（III） and As（V） in the Lihu subterranean stream are 51%, 36% and 59%, respectively. To fully explain the main geochemical factors influencing arsenic attenuation, SPSS 13.0 and CANOCO 4.5 bundled with CanoDraw for Windows were used for simple statistical analysis and redundancy analysis （RDA）. Eight main factors, i.e., sediment iron （SFe）, sediment aluminum （SAI）, sediment calcium （SCa）, sediment organic matter （SOM）, sediment manganese （SMn）, water calcium （WCa^2＋）, water magnesium （WMg^2＋）, and water bicarbonate ion （WILCOX） were extracted from thirteen indicators. Their impacts on arsenic content rank as： SFe〉SCa〉WCa^2＋〉SAl〉wHCO3^-〉SMn〉SOM〉WMg^2＋. Of these factors, SFe, SAl, SCa, SOM, SMn, WMg^2＋ and WCa＆2＋ promote arsenic attenuation, whereas WHCO3^- inhibits it. Further investigation revealed that the redox potential （Eh） and pH are adverse to arsenic removal. The dramatic distinction between karst and non-karst terrain is that calcium and bicarbonate are the primary factors influencing arsenic migration in karst areas due to the high calcium concentration and alkalinity of karst water.

关键词： Karst subterranean stream Sediment Arsenic Geochemical factors Redundancy analysis

Building a PEG-C@MoSe_(2)@CNT heterostructure via in-situ selenidation as highly reversible anodes for Na+batteries

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Science China Chemistry 2023年第2期66卷 475-491页

作者： Yincai Yang Feng Wang Youwen Chen Changmiao Chen Shiguo Zhang Zhen-Qiang Yu chak-Tong au Shuang-Feng Yin Renhua Qiu State Key Laboratory of Chemo/Biosensing and Chemometrics Advanced Catalytic Engineering Research Centre of the Ministry of EducationCollege of Chemistry and Chemical EngineeringSchool of Physics&ElectronicsCollege of Material Science and Chemical EngineeringHunan UniversityChangsha410082China College of Information and Mechatronic Engineering Hunan International Economics UniversityChangsha410082China College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen518000China

Herein,we describe a simple and efficient method to build C@MoSe_(2)@CNT composites that exhibit good electrochemical performance as anode materials for sodium-ion *** protocol uses commercially available and cheap carbon nanotubes(CNT)as the conductive *** selenide(MoSe_(2)),in-situ-synthesized from Mo-ethylene glycol(poly(ethylene glycol)(PEG,M_(n)≈200))complexes,grows along the CNT with a discontinuous morphology,which creates multiple channels for the insertion of Na^(+).Meanwhile,PEG-C provides a thin carbon coating layer to increase *** PEG-200-2-C/MoSe_(2)/CNTat room temperature,the storage at 2 A g^(-1)is 426 m A h g^(-1)after 500 cycles and 212 m A h g^(-1)after 3,000 *** with pure MoSe_(2),density functional theory calculations indicate that the Na^(+)diffusion barrier in the MoSe_(2)of C@MoSe_(2)@CNT effectively decreases from 0.91 to 0.72 e V,hence promoting the reversibility of the Na^(+)storage.

关键词： sodium-ion batteries MoSe_(2) CNT

Tuning photocatalytic performance of Cs_(3)Bi_(2)Br_(9)perovskite by g-C_(3)N_(4)for C(sp^(3))–H bond activation

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Nano Research 2023年第5期16卷 6104-6112页

作者： Zhang-Jun Bai Yu Mao Bing-Hao Wang Lang Chen Sheng Tian Biao Hu You-Ji Li chak-Tong au Shuang-Feng Yin Advanced Catalytic Engineering Research Center of the Ministry of Education State Key Laboratory of Chemo/Biosensing and ChemometricsCollege of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China Key Laboratory of Mineral Cleaner Production and Exploit of Green Functional Materials in Hunan Province Jishou UniversityJishou 416000China College of Chemical Engineering Fuzhou UniversityFuzhou 350002China

All-inorganic halide perovskite(IHP)has been deemed promising in photocatalysis due to tunable bandgap and long lifetime of charge ***,unsatisfactory photocatalytic activity and low stability prevent its practical *** construction of heterojunctions has been proved to be an efficient way to circumvent these ***,g-C_(3)N_(4)nanosheet was employed to construct a 2D/2D(2D:two-dimensional)heterostructure with Cs_(3)Bi_(2)Br_(9)through an electrostatic self-assembly *** to the efficient transfer of photogenerated charge carriers,the activity of Cs_(3)Bi_(2)Br_(9)was boosted with enhanced generation of carbon centered *** optimized 10%Cs_(3)Bi_(2)Br_(9)/g-C_(3)N_(4)composite displays the highest benzaldehyde formation rate of 4.53 mmol·h^(−1)·g^(−1)under visible light,which is 41.8 and 2.3 times that of individual g-C_(3)N_(4)and Cs_(3)Bi_(2)Br_(9),*** stability of Cs_(3)Bi_(2)Br_(9)nanosheets and its selectivity for benzaldehyde(from 65%of Cs_(3)Bi_(2)Br_(9)to 90%of the composite)was enhanced by reducing its surface energy and tuning the reaction pathway,respectively.

关键词： photocatalysis Cs_(3)Bi_(2)Br_(9)/g-C_(3)N_(4)heterojunction selective oxidation toluene benzaldehyde