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Defect-rich potassium amide: A new solid-state potassium ion electrolyte

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Journal of Energy Chemistry 2022年第6期31卷 555-560,I0015页

作者： Jiang Wang Gangtie Lei teng he Hujun Cao Ping Chen Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian 116023LiaoningChina Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education School of ChemistryXiangtan UniversityXiangtan 411105HunanChina

One of the major obstacles to the application of potassium-ion batteries in large-scale energy storage is the lack of safe and effective electrolytes.KNH_(2),a new potassium-ion solid electrolyte has been developed in this study.Its ionic conductivity reaches 4.84×10^(-5)S cm^(-1)at 150°C and can reach3.56×10^(-4)S cm^(-1)after mechanochemical treatment.The result from electron paramagnetic resonance(EPR) measurement shows that the increment of ionic conductivity is dependent on the concentration of nitrogen defects in the KNH_(2) electrolyte.To the best of our knowledge,this is the first report that adopts inorganic amide as an electrolyte for potassium-ion battery and initiates the search for a new amidebased solid electrolyte for an all-solid-state potassium-ion battery.

关键词： Solid-state conductor Potassium ionic conductivity Nitrogen defect Potassium amide

NaH doped TiO_(2)as a high-performance catalyst for Mg/MgH_(2)cycling stability and room temperature absorption

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Journal of Magnesium and Alloys 2023年第8期11卷 2740-2749页

作者： Joshua Adedeji Bolarin Zhao Zhang Hujun Cao Zhi Li teng he Ping Chen Dalian National Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalianP.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China Shangdong Energy Group Co. LTD.No.10777Jingshi RoadJinan CityShandong Province250014P.R.China School of Material Science and Engineering Xi'an Jiaotong UniversityXi'anShaanxi Province710049P.R.China

This paper presents the catalytic effect of NaH doped nanocrystalline TiO_(2)(designated as NaTiOxH)in the improvement of MgH_(2)hydrogen storage properties.The catalyst preparation involves ball milling NaH with TiO_(2)for 3 hr.The addition of 5 wt%NaTiOxH powder into MgH_(2)reduces its operating temperature to∼185℃,which is∼110℃lower than the additive-free as-milled MgH_(2).The composite remarkably desorbs∼7.2 wt%H_(2)within 15 min at∼290℃and reabsorbs∼4.5 wt%H_(2)in 45 min at room temperature under 50 bar H_(2).MgH_(2)dehydrogenation is activated at 57 kJ/mol by the catalyst.More importantly,the addition of 2.5 wt%NaTiOxH catalyst aids MgH_(2)to reversibly produce∼6.1 wt%H_(2)upon 100 cycles within 475 hr at 300℃.Microstructural investigation into the catalyzed MgH_(2)composite reveals a firm contact existing between NaTiOxH and MgH_(2)particles.Meanwhile,the NaTiOxH catalyst consists of catalytically active Ti_(3)O_(5),and“rod-like”Na_(2)Ti_(3)O_(7)species liberated in-situ during preparation;these active species could provide multiple hydrogen diffusion pathways for an improved MgH_(2)sorption process.Furthermore,the elemental characterization identifies the reduced valence states of titanium(Tihenomenon is believed to enhance the mobility of Mg/MgH_(2)electrons by the creation and elimination of oxygen vacancies in the defective(TiO_(2-x))catalyst.Our findings have therefore moved MgH_(2)closer to practical applications.

关键词： Magnesium hydride NaH doped nanocrystalline TiO_(2) Kinetics Room temperature absorption Reversibility

Synthesis of pyrimidines from dinitrogen and carbon

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National Science Review 2022年第12期9卷 220-226页

作者： Xianghui Shi Qianru Wang Chao Qin Li-Jun Wu Yuanjin Chen Gao-Xiang Wang Yongli Cai Wenbo Gao teng he Junnian Wei Jianping Guo Ping Chen Zhenfeng Xi Beijing National Laboratory for Molecular Sciences(BNLMS) Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of EducationCollege of ChemistryPeking University Dalian Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

The element nitrogen and nitrogenous compounds are vital to life.The synthesis of nitrogen-containing compounds using dinitrogen as the nitrogen source,not through ammonia,is of great interest and great value but remains a grand challenge.herein,we describe a strategy to realize this transformation by combining the heterogeneous approach with the homogeneous methodology.The N2molecule was first fixed with carbon and LiH through a one-pot heterogeneous process,forming Li2CN2as an ’activated’nitrogen source with high efficiency.Then subsequent homogeneous treatments of Li2CN2to construct the organic synthon carbodiimide and the RNA/DNA building block pyrimidines were fulfilled.By using15N2as the feedstock,their corresponding15N-labeled carbodiimide and pyrimidines were readily obtained.This homogeneous-heterogeneous synergy strategy will open a new chapter for N2transformation.

关键词： dinitrogen transformation nitrogen fixation N-C bond formation homogeneous-heterogeneous synergy strategy 15n-labeled pyrimidines

Liquid organic hydrogen carriers

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Journal of Energy Chemistry 2015年第5期24卷 587-594页

作者： teng he Qijun Pei Ping Chen Dalian Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

The development of efficient hydrogen storage materials is one of the biggest technical challenges for the coming ＂hydrogen economy＂. The liquid organic hydrogen carriers （LOHCs） with high hydrogen contents, reversibilities and moderate dehydrogenation kinetics have been considered as an alternative option supplementing the extensively investigated inorganic hydride systems. In this review, LOHCs for long distance H2 transport and for onboard application will be discussed with the focuses of the design and development of LOHCs and their hydrogenation ＆ dehydrogenation catalyses.

关键词： Liquid organic hydrogen carrier CycloalkanesheterocycleFormic acid Catalysis

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

不同FCM聚类算法的模糊时间序列预测模型比较

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数学的实践与认识 2024年第5期54卷 128-140页

作者：王敏何腾松彭鼎贵州师范大学数学科学学院贵州贵阳550025

在模糊时间序列预测模型通常涉及到论域的划分,通常用FCM聚类算法来对论域进行划分,或者用样本点和聚类中心计算出的相似性距离(DTW)来代替传统的欧式距离,即得到DTW-FCM聚类算法来对论域划分.其中基于DTW的FCM聚类算法(DTW-FCM),引入... 详细信息

在模糊时间序列预测模型通常涉及到论域的划分,通常用FCM聚类算法来对论域进行划分,或者用样本点和聚类中心计算出的相似性距离(DTW)来代替传统的欧式距离,即得到DTW-FCM聚类算法来对论域划分.其中基于DTW的FCM聚类算法(DTW-FCM),引入了一个负指数变量,以获得更好的鲁棒性,由此设计出基于DTW改良后的FCM聚类算法(DTW-MFCM).最后将Alabama大学入学人数预测案例和美国二氧化碳排放总量实列应用到该模型上,将预测结果与其他模糊时间序列预测模型进行比较,结果表明该模型的预测精度和稳定性明显提高,优于其他经典模型.

关键词：模糊时间序列鲁棒性 DTW-MFCM算法预测模型

The Roles of Alkali/Alkaline Earth Metals in the Materials Design and Development for Hydrogen Storage

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Accounts of Materials Research 2021年第9期2卷 726-738页

作者： teng he Hujun Cao Ping Chen Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian 116023China Dalian Institute of Chemical Physics and State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

CONSPECTUS:Hydrogen storage for onboard applications has been recognized as a grand challenge for the large-scale implementation of hydrogen fuel cell vehicles.Tremendous research efforts have thus been devoted to the design and development of hydrides of lightweight elements(HLEs).A prominent feature of these materials is the indispensable ingredient of alkali/alkaline earth cations.Alkali alkaline earth metals(AMs)are highly reactive and have a rich coordination chemistry.As a matter of fact,an AM cation can form a complete range of compounds with hydrogenous anions,such as H−,[NH2]−,[BH4]−,[AlH4]−,[NH2BH3]−,[TMHX]−,[R-CH2−NH]−,[R-CH2−O]−,etc.,and,thus,tune the Al−H,N−H,B−H,and C−H bond strengths for hydrogen storage.In this Account,our research efforts in the development of AM amide-hydride composites,AM amidoboranes,and metalorganic hydrides for hydrogen storage are reviewed.A partial substitution of the H in NH3 by AM gives rise to solid AM amides or imides.Those compounds can react with AM hydride(AMH)to produce H2.This is driven by the redox reaction between a protic H(N)and hydridic H(AM).A variety of amide-hydride composites holding promise for hydrogen storage were thus developed,including LiNH2-hydride,Mg(NH2)2-hydride,and complex amide-hydride composites.For amidoboranes,the substitution of H(N)in ammonia borane(AB)by AM transforms the molecular crystal AB into amidoboranes with an ionic crystal structure,leading to significant changes in terms of charge distribution,bond length,intermolecular forces,and so on,which in turn results in enhanced dehydrogenation properties.For metalorganic hydrides,through reacting AM compounds(usually AM hydride)with aliphatic,carbocyclic,or heterocyclic organic hydrides having“reactive protic H”,corresponding metalorganic hydrides are formed.Because of the electron-donating nature of AM,the strengths of the C−H bond in metal-organic hydrides can be modulated.For each material system,we will introduce the synthesis of materials,show their performances,correlate the hydr

关键词： hydride Alkali earth

OBE理念下高职“机械设计基础”课程资源建设机制探究

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职业教育研究 2024年第4期 82-86页

作者：何腾飞湖南电气职业技术学院湖南湘潭411101

基于OBE理念,探讨高职“机械设计基础”课程建设逻辑。提出五个建设步骤:修订课程标准,优化教材结构;双师合力,共建理实资源;制定建设标准,实施评估督导;延伸相关课程,促推知识升级;优化评估反馈,注重持续改进。

关键词： OBE 机械设计基础课程建设

Effects of doping FeCl3 on hydrogen storage properties of Li-N-H system

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Progress in Natural Science:Materials International 2017年第1期27卷 139-143页

作者： Weijin Zhang Han Wang Hujun Cao teng he Jianping Guo Guotao Wu Ping Chen Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences Institute of Materials Research Materials Technology Helmholtz-Zentrum Geesthacht

The effects of doping FeCl;on the LiNH;-2LiH system were investigated systematically. FeCl;was prior to react with LiH during ball milling their mixtures. The metallic Fe, which is generated from metathesis reaction between FeCl;and LiH, plays an important role on improving the dehydrogenation kinetics of LiNH;-2LiH system. The results indicated that the dehydrogenation peak and ending temperatures of the doped 1 mol%FeCl;sample shifted to low temperatures, and the dehydrogenation active energy changed from 102.45 k J/mol to 87.52 k J/mol. While increasing the amount of FeCl;, an excess of LiCl, the by-product of metathesis reaction between FeCl;and Li H, can stabilize LiNH;and thus hinder hydrogen desorption. The dehydrogenation product is a new solid cubic phase solution of lithium imide-chloride. The high limit of the solid solution of LiCl and Li;NH is near the molar ratio of 1:1.

关键词： Hydrogen storage Iron trichloride Lithium amide Reaction kinetics Solid solution Lithium imide-chloride