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Nitrogen-doped carbon-coated hollow SnS_(2)/nis microflowers for high-performance lithium storage

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Frontiers of Materials Science 2023年第3期17卷 119-129页

作者： Junhai Wang Jiandong Zheng Liping Gao Qingshan Dai Sang Woo Joo Jiarui Huang School of Material and Chemical Engineering Chuzhou UniversityChuzhou 239000China Key Laboratory of Functional Molecular Solids of the Ministry of Education College of Chemistry and Materials ScienceAnhui Normal UniversityWuhu 241002China School of Mechanical Engineering Yeungnam UniversityGyeongsanGyeongbuk 38541Republic of Korea

Nitrogen-doped carbon-coated hollow SnS_(2)/nis(SnS_(2)/nis@N–C)microflowers were obtained using nisn(OH)6 nanospheres as the template via a solventthermal method followed by the polydopamine coating and carbonization process.When served as an anode material for lithium-ion batteries,such hollow SnS_(2)/nis@N–C microflowers exhibited a capacity of 403.5 mAh·g^(−1) at 2.0 A·g^(−1) over 200 cycles and good rate performance.The electrochemical reaction kinetics of this anode was analyzed,and the morphologies and structures of anode materials after the cycling test were characterized.The high stability and good rate performance were mainly due to bimetallic synergy,hollow micro/nanostructure,and nitrogen-doped carbon layers.The revealed excellent electrochemical energy storage properties of hollow SnS_(2)/nis@N–C microflowers in this study highlight their potential as the anode material.

关键词： SnS_(2) nis microflower hollow structure nitrogen-doped carbon anode lithium-ion battery

Self-assembled dandelion-like nis nanowires on biomass-based carbon aerogels as electrode material for hybrid supercapacitors

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Frontiers of Materials Science 2023年第3期17卷 95-105页

作者： Chunfei Lv Ranran Guo Xiaojun Ma Yujuan Qiu College of Light Industry Science and Engineering Tianjin University of Science&TechnologyTianjin 300222China

Carbon aerogels derived from biomass have low specific capacity due to the underutilized structure,limiting their application in high-performance supercapacitors.In this work,the hierarchical nickel sulfide/carbon aerogels from liquefied wood(LWCA-nis)were synthesized via a simple two-step hydrothermal method.Benefitting from the unique 3D coral-like network structure of LWCA,selfassembled nis nanowires with the dandelion-like structure showed high specific surface(389.1 m^(2)·g^(−1))and hierarchical pore structure,which increased affluent exposure of numerous active sites and structural stability,causing superior energy storage performance.As expected,LWCA-nis displayed high specific capacity(131.5 mAh·g^(−1) at 1 A·g^(−1)),good rate performance,and highly reversible and excellent cycle stability(13.1%capacity fading after 5000 cycles)in the electrochemical test.Furthermore,a symmetrical supercapacitor using LWCA-nis-10 as the electrode material delivered an energy density of 12.7 Wh·kg^(−1) at 299.85 W·kg^(−1).Therefore,the synthesized LWCA-nis composite was an economical and sustainable candidate for the electrodes of highperformance supercapacitors.

关键词： carbon aerogel liquefied wood nis self-assembly electrochemistry

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自适应量子储层计算与多任务学习

Science Bulletin 2023年第20期68卷 2321-2329,M0004页

作者：夏威邹杰邱型泽陈锋朱兵李春贺邓东灵李晓鹏 State Key Laboratory of Surface Physics Key Laboratory of Micro and Nano Photonic Structures(MOE)and Department of PhysicsFudan UniversityShanghai 200433China School of Physics Science and Engineering Tongji UniversityShanghai 200092China Institute of Science and Technology for Brain-Inspired Intelligence Fudan UniversityShanghai 200433China Hong Kong and Shang Hai Banking Corporation Laboratory Hong Kong and Shang Hai Banking Corporation Holdings PLCGuangzhou 511458China Shanghai Center for Mathematical Sciences and School of Mathematical Sciences Fudan UniversityShanghai 200433China Center for Quantum Information IIISTsinghua UniversityBeijing 100084China Shanghai Qi Zhi Institute AI TowerShanghai 200232China Shanghai Research Center for Quantum Sciences Shanghai 201315China

随着实验技术的快速发展,含噪声的中等规模量子(nisQ)设备的可编程性越来越高,人们能够更好地利用量子计算的优势.本文利用可编程的nisQ设备的复杂动力学来进行量子储层计算,并通过使用遗传算法来优化该过程.令人惊讶的是,单个自适应量... 详细信息

随着实验技术的快速发展,含噪声的中等规模量子(nisQ)设备的可编程性越来越高,人们能够更好地利用量子计算的优势.本文利用可编程的nisQ设备的复杂动力学来进行量子储层计算,并通过使用遗传算法来优化该过程.令人惊讶的是,单个自适应量子储层可以同时学习多个任务,包括振荡型基因网络、混沌型基因网络和分数阶蔡氏电路.通过自适应量子储层计算,这些任务的学习性能得到了显著提升,远远超过了经典储层计算的表现.此外,本文还将自适应量子储层计算应用于外汇市场,相较于经典储层计算,它能更准确地捕捉汇率的随机演化.通过与经典储层计算的比较,本文突出了量子相干性在量子储层计算中的重要性,并验证了量子相干性是实现卓越学习性能的关键.研究结果表明,自适应量子储层计算能够充分发挥nisQ设备的量子计算能力,并在通用人工智能的发展方面具有巨大潜力.

关键词：基因网络多任务学习量子计算量子相干性 nis 遗传算法蔡氏电路外汇市场

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中国教育网络 2024年第1期 4-4页

近期,欧盟通过首个网络安全认证计划一一《欧洲共同标准网络安全计划》(EUCC)。EUCC由欧盟网络安全局(EnisA)与成员国协同起草,以自愿为基础,允许信息和通信技术(ICT)供应商通过欧盟的通用评估流程,保证其技术组件、硬件和软件等数字产... 详细信息

近期,欧盟通过首个网络安全认证计划一一《欧洲共同标准网络安全计划》(EUCC)。EUCC由欧盟网络安全局(EnisA)与成员国协同起草,以自愿为基础,允许信息和通信技术(ICT)供应商通过欧盟的通用评估流程,保证其技术组件、硬件和软件等数字产品的网络安全,激励供应商遵守网络安全认证要求。EUCC根据与产品、服务或流程的预期用途相关的风险水平,提出了两个级别的保证。

关键词：网络安全信息和通信技术 nis ICT EUC 供应商 UCC 评估流程

基于柔性MXenes/石墨烯纤维直接电沉积nis构建非酶葡萄糖传感器

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分析试验室 2023年第6期42卷 800-806页

作者：李江李作鹏罗宿星丁志明白云峰樊佩武美霞郭永山西大同大学化学与化工学院大同037009 遵义师范学院化学化工学院遵义563006 大同市第五人民医院综合检验科大同037009

使用一步电沉积法在二维过渡金属碳(氮)化物(MXenes)/石墨烯纤维(GF)上直接合成nis,制备非酶葡萄糖传感器。在最佳条件下,nis/MXenes/GF微电极传感器检测葡萄糖,在葡萄糖浓度2.5~5000μmol/L范围内呈良好的线性关系,检出限为1.64μmol/L... 详细信息

使用一步电沉积法在二维过渡金属碳(氮)化物(MXenes)/石墨烯纤维(GF)上直接合成nis,制备非酶葡萄糖传感器。在最佳条件下,nis/MXenes/GF微电极传感器检测葡萄糖,在葡萄糖浓度2.5~5000μmol/L范围内呈良好的线性关系,检出限为1.64μmol/L,灵敏度3951.35μA·L/(mmol·cm^(2))。结果表明,制备的nis/MXenes/GF柔性纤维状微电极可作为生物传感器的电极材料。

关键词：石墨烯纤维微电极 MXenes nis 电沉积葡萄糖

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Immobilization of nis nanoparticles on N-doped carbon fiber aerogels as advanced electrode materials for supercapacitors

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Nano Research 2016年第9期9卷 2747-2759页

作者： Youfang Zhang Lizeng Zuo Longsheng Zhang Jiajie Yan Hengyi Lu Wei Fan Tianxi Liu State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan University220 Handan RoadShanghai 200433China State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua University2999 North Renmin RoadShanghai 201620China

nis nanoparticles (NPs) with excellent electrochemical capacitance have attracted considerable attention as cost-effective energy-storage materials for supercapacitors in recent years. Preventing the aggregation and increasing the conductivity of nis NPs are key to fully realizing their excellent electrochemical properties. In this work, nis/N-doped carbon fiber aerogel (N-CFA) nanocomposites were obtained easily through the combination of polymerization, carbonization, and a one-step solvothermal reaction. N-CFA derived from polydopamine (PDA)-coated cotton wool was used as a template for the construction of hierarchical nis/N-CFA nanocomposites, in which nis NPs are uniformly immobilized on the surface of N-CFA. In this nanostructured system, N-CFA containing abundant nanofibers not only provides active regions for the growth of nis NPs to prevent their aggregation, but also offers short pathways for the transport of electrons and ions. The electrochemical properties of the obtained nis/N-CFA nanocomposites were investigated by cyclic voltammetry, galvanostatic charge–discharge, and alternating current impedance measurements. The optimized nis/N-CFA nanocomposite exhibits a high specific capacitance of 1,612.5 F·g‒1 at a charge/discharge current density of 1 A·g‒1 and excellent rate capacitance retention of 66.7% at 20 A·g‒1. The excellent electrochemical properties of nis/N-CFA nanocomposites make these materials promising electrode materials for supercapacitors.

关键词： nis cotton wool carbon fiber aerogels N-doping supercapacitors

Enhanced photocatalytic N2 fixation by promoting N2 adsorption with a co-catalyst

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Science Bulletin 2019年第13期64卷 918-925页

作者： Xiang Gao Li An Dan Qu Wenshuai Jiang Yanxiao Chai Shaorui Sun Xingyuan Liu Zaicheng Sun State Key Laboratory of Luminescence and Applications Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China University of Chinese Academy of Sciences Beijing 100190China Center of Excellence for Environmental Safety and Biological Effects Beijing Key Laboratory of Green Catalysis and Separation Department of Chemistry and Chemical EngineeringSchool of Environmental and EnergyBeijing University of TechnologyBeijing 100124China

Photocatalytic N2 fixation involves a nitrogen reduction reaction on the surface of the photocatalyst to convert N2 into ammonia.Currently,the adsorption of N2 is the limiting step for the N2 reduction reaction on the surface of the catalyst.Based on the concept of photocatalytic water splitting,the photocatalytic efficiency can be greatly enhanced by introducing a co-catalyst.In this report,we proposed a new strategy,namely,the loading of a nis co-catalyst on CdS nanorods for photocatalytic N2 fixation.Theoretical calculation results indicated that N2 was effectively adsorbed onto the nis/CdS surface.Temperature programmed desorption studies confirmed that the N2 molecules preferred to adsorb onto the nis/CdS surface.Linear sweep voltammetry results revealed that the overpotential of the N2 reduction reaction was reduced by loading nis.Furthermore,transient photocurrent and electrochemical impedance spectroscopy indicated that the charge separation was enhanced by introducing nis.Photocatalytic N2 fixation was carried out in the presence of the catalyst dispersed in water without any sacrificial agent.As a result,1.0 wt% nis/CdS achieved an ammonia production rate of 2.8 and 1.7 mg L-1 for the first hour under full spectrum and visible light(λ>420 nm),respectively.The catalyst demonstrated apparent quantum efficiencies of 0.76%,0.39% and 0.09% at 420,475 and 520 nm,res pectively.This study provides a new method to promote the photocatalytic efficiency of N2 fixation.

关键词： N2 fixation Photocatalyst Co-catalyst N2 adsorption nis

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α-Ni(OH)2正极材料的制备、改性与电化学性能研究

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α-Ni(OH)2正极材料的制备、改性与电化学性能研究

作者：潘云鹏燕山大学

学位级别：硕士

能源与可持续发展问题逐渐成为世界各国发展历程中所面临的巨大挑战。能源需求的迅猛增长和生态环境恶化的加剧使人们将目光转投到新型清洁能源与储能装置的研发与应用上。镍氢电池(Ni/MH)以其清洁环保、低温性能出色以及高安全性等优... 详细信息

能源与可持续发展问题逐渐成为世界各国发展历程中所面临的巨大挑战。能源需求的迅猛增长和生态环境恶化的加剧使人们将目光转投到新型清洁能源与储能装置的研发与应用上。镍氢电池(Ni/MH)以其清洁环保、低温性能出色以及高安全性等优点长期活跃在电化学储能装置领域。目前商用的镍氢电池的正极材料以β-Ni(OH)为主,其在进行电化学循环时只有1 mol电子发生转移,理论容量仅有289mAh/g,逐渐难以满足需求。而α-Ni(OH)作为Ni(OH)的另一种相结构,在充放电反应过程中会转移1.67 mol电子,使得以α-Ni(OH)作为正极的镍氢电池拥有更高的理论比容量。尽管如此,在实际应用中发现α-Ni(OH)在KOH电解液中容易发生α-Ni(OH)→β-Ni(OH)的转化;并且发现其在制备成电极后的导电性并不是很好,使得大部分的活性物质不参与反应,进而限制了其生产应用。因此,本研究围绕提升α-Ni(OH)容量和循环稳定性展开研究。在这项工作中,硝酸镍被用作镍源以提供Ni,表面活性剂选则使用聚乙烯吡咯烷酮(PVP)以控样品的形貌,利用水热法所提供的高温高压环境使尿素缓慢分解以得到OH来沉淀Ni,制备出α-Ni(OH)。为了改善导电性能差的缺点,将制备的α-Ni(OH)与硫脲共同水热,利用S与OH的阴离子交换反应,将nis纳米片包覆在α-Ni(OH)微球表面;采用Y元素对α-Ni(OH)进行单掺杂,以改善样品在碱液中的稳定性;最后将上述成果进行优化,制备出具有良好导电性以及循环稳定性的nis包覆的Ni-Y LDHs。获得的样品还在形态结构和性能方面进行了表征,并详细讨论了电极材料微观结构和性能之间的内在关系。结果如下:(1)使用水热法合成了纳米级花球状α-Ni(OH),样品具有多孔道结构并且高度分散。性能的测试表明,样品在0.2C(室温下)可以放出307.4 mAh/g的电量,比目前商业化的β-Ni(OH)放电容量高出～20 mAh/g。通过二次水热方法将nis包覆在球形α-Ni(OH)表面。形貌表征证实,包覆后的样品仍具有良好的球形结构。电化学测试表明,样品S-Ni-4(α-Ni(OH):硫脲=5:4)在0.2C下的放电容量高达369.9 mAh/g,在3C和5C下也具有290.1 mAh/g和254.4 mAh/g放电容量,呈现出良好的高倍率放电性能。此外,在1C充放电条件下循环200次后,容量保持率可达到～89%。研究结果表明,孔道结构的保留与适度的nis包覆,在电化学循环中对降低阻抗、提高电荷迁移速率等方面做出了协同贡献,进而提升了α-Ni(OH)的综合电化学性能。(2)在合成α-Ni(OH)的实验基础上,采用金属离子Y进行了化学掺杂。结果表明,适量的Y元素进入到晶格内部后,促使α-Ni(OH)自组装形式由纳米片变成纳米线。电化学测试结果显示,掺杂量为2 mol%Y元素的样品在常温下0.2C的放电容量达到337 mAh/g。特别关注的是,样品在充放电循环400次后(1C),放电容量保持率可高达～96%。样品的测试表明,Y的引入不仅可以使α-Ni(OH)的析氧电位升高,还可以使NiO层板的正电荷增多,从而吸引更多的阴离子插入到层间。在二者共同的影响下α-Ni(OH)的循环稳定性和容量均得到了显著提高。(3)最后,结合了上述两种方案的优点,制备出了具有良好导电性和循环稳定性的nis包覆Ni-Y LDHs样品。结果显示,样品在室温下0.2C的放电容量高达390 mAh/g,且在1C充放电条件下循环400圈后的保持率高达～88%。本研究结果为Ni/MH电池的提供了一种容量高、寿命长的Ni(OH)正极材料,同时为镍基水系电池的电极材料也提供了新选择。

关键词：镍氢电池 α-Ni(OH)2 nis 金属掺杂电化学性能

The synthesis of pillared nickel-substituted saponite and its hydroisomerization activity

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Chinese Journal of Chemistry 1993年第6期11卷 509-516页

作者： Da-Zhen Jiang Tie Sun Zi-Yang Liu En-Ze Min Ming-Yuan He Department of Chemistry Jilin University Changchun 130023 Research Institute of Petroleum Processing Beijing 100083

Nickel-substituted saponite clays (nis) were synthesized. The pillared clays noted Pnis were prepared from the nis intercalated with large inorganic cations such as [Al_(13)O_4(OH)_(24). (H_2O)_(12)]^(7+). It is found that the pillar density is correlative with aluminium content in the tetra- hedral sheet of nis. The results from TPR indicate that the palladium loaded on samples promotes the reduction of the nickel ion in the octahedral sheet. The pillared clays impregnated with Pd^(2+) noted PdPnis show excellent hydroisomerization property which is much better than that of nickel substituted mica-montmorillonite pillared with silicon oxide oligomer noted PdPSMM. The hexane conversion increases with the content of aluminium ion in the tetrahedral sheet, whereas the change of the selectivity of isomerization is not obvious.

关键词： nis The synthesis of pillared nickel-substituted saponite and its hydroisomerization activity

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