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Facile synthesis and enhanced catalytic activity of electrochemically dealloyed platinum–nickel nanoparticles towards formic acid electro-oxidation

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Journal of Energy Chemistry 2019年第8期28卷 9-16,I0001页

作者： Maryam Kiani Jie Zhang Yan Luo Yihan Chen Jinwei Chen Jinlong Fan Gang Wang Ruilin Wang College of Materials Science and Engineering Sichuan University

To obtain the electrocatalyst with an improved electrocatalytic performance towards formic acid electrooxidation(FAEO), a simple impregnation method is used to prepare Pt3Ni nanoparticles loaded on carbon black, assisted with electrochemically dealloying process. The X-ray powder diffraction(XRD) results as well as transmission electron microscopy(TEM) analysis of as-synthesized electrocatalyst demonstrates that the reduction temperature has a great influence on the FAEO activity of the dealloyed Pt3Ni nanoparticles. X-ray photoelectron spectroscopy(XPS) analyses confirm the variation in the electronic structure of platinum by incorporation of nickel atoms which reduces chemisorption of toxic carbon monoxide and promotes the dehydrogenation pathway of FAEO. The size of the dealloyed Pt3Ni nanoparticles remains within the range of about 2.7 nm. All electrochemical results illustrate that the performance of the asobtained electrocatalyst towards the FAEO is significantly enhanced. Moreover, the carbon black content,incorporation of Ni atoms, and reduction temperature conditions have been proven to be the key factors for modification of the crystal structure and morphology which leads to enhanced catalytic performance.

关键词： Formic acid electro-oxidation Electrocatalysis Pt3Ni nanoparticles Dealloying dehydrogenation pathway

A study on hydrogen uptake and release of a eutectic mixture of biphenyl and diphenyl ether

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Journal of Energy Chemistry 2020年第3期29卷 11-16页

作者： Munjeong Jang Byeong Soo Shin Young Suk Jo Jeong Won Kang Sang Kyu Kwak Chang Won Yoon Hyangsoo Jeong Center for Hydrogen Fuel Cell Research Korea Institute of Science and Technology(KIST)5 Hwarang-ro 14-gilSeongbuk-guSeoul 02792Republic of Korea Divison of Energy and Environment Technology KIST SchoolKorea University of Science and Technology5 Hwarang-ro 14-gilSeongbuk-guSeoul 02792Republic of Korea Department of Chemical and Biological Engineering Korea UniversityAnam-ro 145Seongbuk-guSeoul 02841Republic of Korea School of Energy and Chemical Engineering Ulsan National Institute of Science and Technology50UNIST-gilUlsan 44919Republic of Korea KHU-KIST Department of Converging Science and Technology Kyung Hee University26 Kyungheedae-roDongdaemun-guSeoul 02447Republic of Korea

Hydrogen storage in Liquid Organic Hydrogen Carrier(LOHC)systems is appealing for the safe storage and distribution of excess renewable energy via existing gasoline infrastructures to end-users.We present the eutectic mixture of biphenyl and diphenyl ether of its first use as a LOHC material.The material is hydrogenated with 99%selectivity without the cleavage of C–O bond,with commercial heterogeneous catalysts,which is confirmed by nuclear magnetic spectroscopy and gas chromatography-mass spectrometry.Equilibrium concentration,dehydrogenation enthalpy,and thermo-neutral temperature are calculated using a density functional theory.The results indicate that O-atom-containing material exhibits more favorable dehydrogenation thermodynamics than that of the hydrocarbon analogue.The H2-rich material contains6.8 wt%of gravimetric hydrogen storage capacity.A preliminary study of catalytic dehydrogenation on a continuous reactor is presented to demonstrate a reversibility of this material.

关键词： Hydrogen storage Liquid organic hydrogen carrier Diphenyl ether dehydrogenation Thermodynamics

Computational mechanistic investigation of radiation damage of adenine induced by hydroxyl radicals

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Chinese Physics B 2018年第2期27卷 64-70页

作者：谈荣日刘慧宣寻大毛宗文军 College of Communication and Electronics Jiangxi Science & Technology Normal University Institute of High Energy Physics Chinese Academy of Sciences

The radiation damage of adenine base was studied by B3LYP and MP2 methods in the presence of hydroxyl radicals to probe the reactivities of five possible sites of an isolated adenine molecule. Both methods predict that the C8 site is the more vulnerable than the other sites. For its bonding covalently with the hydroxyl radicals, B3LYP predicts a barrierless pathway, while MP2 finds a transition state with an energy of 106.1 kJ/mol. For the hydroxylation at the C2 site, the barrier was calculated to be 165.3 kJ/mol using MP2 method. For the dehydrogenation reactions at five sites of adenine, B3LYP method predicts that the free energy barrier decreases in the order of H8 〉 H2 〉 HN62 〉 HN61 〉 HN9.

关键词： DNA damage radicals adenine dehydrogenation

Damage mechanism of hydroxyl radicals toward adenine–thymine base pair

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Chinese Physics B 2014年第2期23卷 431-436页

作者：谈荣日王东琪张丰收 College of Communication and Electronics Jiangxi Science & Technology Normal University The Key Laboratory of Beam Technology and Material Modification of the Ministry of Education College of Nuclear Science and TechnologyBeijing Normal University Guizhou Key Laboratory for Photoelectric and Application College of ScienceGuizhou University Institute of High Energy Physics Chinese Academy of Sciences Beijing Radiation Center Center of Theoretical Nuclear Physics National Laboratory of the Heavy Ion Accelerator of Lanzhou

The adenine-thymine base pair was studied in the presence of hydroxyl radicals in order to probe the hydrogen bond effect. The results show that the hydrogen bonds have little effect on the hydroxylation and dehydrogenation happened at the sites, which are not involved in a hydrogen bond, while at the sites involved in hydrogen bond formation in the base pair, the reaction becomes more difficult, both in view of the free energy barrier and the exothermicity. With a 6-311 ＋＋G（d,p） level of description, both B3LYP and MP2 methods confirm that the C8 site of isolated adenine has the highest possibility to form covalent bond with the hydroxyl radicals, though with different energetics： B3LYP predicts a barrierless pathway, while MP2 finds a transition state with an energy of 106.1 kJ/mol. For the dehydrogenation reactions, B3LYP method predicts that the free energy barrier increases in the order of HN9 〈 HN61 〈 HN62 〈 H2 〈 H8.

关键词： DNA damage hydrogen bond effect hydroxylation dehydrogenation

Stabilization of low-valence transition metal towards advanced catalytic effects on the hydrogen storage performance of magnesium hydride

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Journal of Magnesium and Alloys 2021年第2期9卷 647-657页

作者： Jian Zhang Shuai Yan Guanglin Xia Xiaojie Zhou Xianzheng Lu Linping Yu Xuebin Yu Ping Peng Hunan Provincial Key Laboratory of Intelligent Manufacturing Technology for High-performance Mechanical Equipment Changsha University of Science and TechnologyChangsha 410114China Department of Materials Science Fudan UniversityShanghai 200433China School of Chemistry and Biological Engineering Changsha University of Science and TechnologyChangsha 410114China College of Materials Science and Engineering Hunan UniversityChangsha 410082China

Magnesium hydride(MgH_(2))has been widely regarded as a potential hydrogen storage material owing to its high gravimetric and volumetric capacity.Its sluggish kinetics and high activation energy barrier,however,severely limit its practical application.Transition metal oxides(TMOs)have been extensively used as catalysts to improve the hydrogen storage performance of MgH_(2),but the low-valence transition metal(TM)ions,resulting from the reduction of TMOs accompanied by the formation of inactive Mg O,have been demonstrated to be the most effective components.Herein,we theoretically and experimentally confirm that the doping of low-valence TMs into Mg O could effectively weaken the Mg-H bonds and decrease the energy required for hydrogen desorption from MgH_(2),leading to superior catalytic activity compared to both TMOs and Mg O.In particular,the apparent activation energy for the dehydrogenation of Mg(Nb)O-catalyzed MgH_(2)could be reduced to only 84.1 kJ mol^(-1),and the reversible capacity could reach around 7 wt.%after 5 cycles with a capacity retention of 96%.Detailed theoretical calculations confirm that the remarkable orbital hybridization between Mg(Nb)O and MgH_(2)promotes charge transfer from MgO to the MgH_(2)monomer,resulting in significantly weakened stability of MgH_(2),which could effectively enhance its hydrogen storage performance.

关键词： Magnesium hydride Hydrogen storage dehydrogenation Catalysts First-principles calculations Solid-solution

Kinetic studies of reversible hydrogen storage over sodium phenoxide-cyclohexanolate pair in aqueous solution

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Journal of Energy Chemistry 2019年第12期28卷 244-248页

作者： Yang Yu Qijun Pei Teng He Ping Chen Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sdences Beijing 100049China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina Collaborative Innovation Center of Chemistry for Energy Materials(iChEM-2011) Xiamen UniversityXiamen 361005FujianChina

With reduced dehydrogenation enthalpy change and reduced dehydrogenation temperature compared with its phenol-cyclohexanol pair,sodium phenoxide-cyclohexanolate pair developed recently is promising for large-scale energy storage and long-distance hydrogen transportation.In the present work,we investigate the kinetic behavior of the pair in the hydrogenation and dehydrogenation in water over three commercial catalysts.It is shown that 5%Ru/Al2O3 and 5%Pt/C perform well in the hydrogenation and dehydrogenation,respectively.Kinetic analyses show that the hydrogenation of sodium phenoxide is of first-order with respect to H2 pressure and zero-order to the concentration of sodium phenoxide in the presence of Ru/Al2O3 catalyst.>99%conversion of cyclohexanol and>99%selectivity to phenoxide can be achieved in the dehydrogenation catalyzed by Pt/C catalyst and in the presence of Na OH at 100℃,where cyclohexanone was observed as an intermediate.According to the kinetic analysis,the hydrogenation of sodium phenoxide may undergo the hydrolysis and hydrogenation pathway.For the dehydrogenation,an intermediate,i.e.,cyclohexanone,was detected and two possible pathways are proposed accordingly.

关键词： Hydrogen storage Hydrogenation dehydrogenation Sodium phenoxide Kinetic analysis

Ultrafine PdAg alloy nanoparticles anchored on NH2-functionalized 2D/2D TiO_(2) nanosheet/rGO composite as efficient and reusable catalyst for hydrogen release from additive-free formic acid at room temperature

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Journal of Energy Chemistry 2021年第8期30卷 455-464,I0010页

作者： Xi Zhao Ping Dai Dongyan Xu Xumei Tao Xien Liu Qingjie Ge State Key Laboratory Base of Eco-chemical Engineering College of Chemical EngineeringQingdao University of Science&TechnologyQingdao 266042China Shandong Provincial Key Laboratory Of Polymer Material Advanced Manufacturing Technology College of Electromechanical EngineeringQingdao University of Science&TechnologyQingdao 266061China Dalian National Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China State Key Laboratory of High-efficiency Coal Utilization and Green Chemical Engineering College of Chemistry and Chemical EngineeringNingxia University750021 YinchuanChina

A 2 D-2 D titanium dioxide nanosheet-reduced graphene oxide(TNS-r GO)composite with better electronic conductivity and hydrophilicity was prepared by the hydrothermal method.The as-obtained TNS-r GO composite was further functionalized with 3-aminopropyltriethoxysilane(APTES)to provide a large amount of-NH2 groups on the surface for anchoring ultrafine Pd Ag alloy nanoparticles with an average particle size of 1.69 nm by a facile wet reduction approach.Benefiting from the combined effects of well-dispersed Pd Ag alloy nanoparticles,facilitated electron transfer from TNS-r GO to Pd,and increased electron density of active sites,the Pd8 Ag_(1)/NH_(2)-TNS-r GO catalyst exhibited excellent activity towards dehydrogenation of formic acid without adding any additives at 298 K,corresponding to an initial turn over frequency as high as 1090 h-1,which is much higher than that of most other state-of-theart catalysts.

关键词： Formic acid dehydrogenation TNS-rGO composite PdAg alloy Amine-functionalization

Integrating photocatalytic reduction of CO2 with selective oxidation of tetrahydroisoquinoline over InP–In2O3 Z-scheme p-n junction

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Science China Chemistry 2020年第1期63卷 28-34页

作者： Bohang Zhao Yi Huang Dali Liu Yifu Yu Bin Zhang Department of Chemistry Tianjin Key Laboratory of Molecular Optoelectronic SciencesSchool of ScienceTianjin UniversityTianjin 300072China Institute of Molecular Plus Tianjin UniversityTianjin 300072China Collaborative Innovation Center of Chemical Science and Engineering Tianjin 300072China

The development of a facile strategy to construct stable hierarchal porous heterogeneous photocatalysts remains a great challenge for efficient CO2 reduction.Additionally,hole-trapping sacrificial agents(e.g.,triethanolamine,triethylamine,and methanol)are mostly necessary,which produce useless chemicals,and thus cause costs/environmental concerns.Therefore,utilizing oxidation ability of holes to develop an alternative photooxidation reaction to produce value-added chemicals,especially coupled with CO2 photoreduction,is highly desirable.Here,an in situ partial phosphating method of In2O3 is reported for synthesizing In P–In2O3 p-n junction.A highly selective photooxidation of tetrahydroisoquinoline(THIQ)into value-added dihydroisoquinoline(DHIQ)is to replace the hole driven oxidation of typical sacrificial agents.Meanwhile,the photoelectrons of In P–In2O3 p-n junction can induce the efficient photoreduction of CO2 to CO with high selectivity and stability.The evolution rates of DHIQ and CO are 2 and 3.8 times higher than those of the corresponding In2O3 n-type precursor,respectively.In situ irradiated X-ray photoelectron spectroscopy and electron spin resonance are utilized to confirm that the direct Z-scheme mechanism of In P–In2O3 p-n junction accelerate the efficient separation of photocarriers.

关键词： CO2 reduction dehydrogenation photocatalysis Z-scheme tetrahydroisoquinoline

Dienone-phenol Rearrangement of C-9 Oxygenated Decalinic Dienone and Analogs through B-Ring Cleavage

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Chinese Chemical Letters 2003年第7期14卷 689-692页

作者： Jing Chun CHEN Gang ZHOU Wei Dong LI Yu Lin LI National Laboratory of Applied Organic Chemistry and Institute of Organic Chemistry Lanzhou UniversityLanzhou 730000

dehydrogenation of 9-hydroxy decalinic enones and analogs with DDQ resulted in a formal dienone-phenol type rearrangement via B-ring cleavage, while the corresponding dienone acetates underwent base-catalyzed formal d... 详细信息

关键词： Dienone-phenol rearrangement decalinic dienone dehydrogenation DDQ.