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基于LF-NMR的蓖麻油脱水过程中指标监测研究
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作者 王琰 闫枫丹 +5 位作者 孙悦文 许盼盼 刘梦洋 李文龙 彭丹 李军 《中国油脂》 北大核心 2025年第9期124-130,共7页
旨在建立一种脱水蓖麻油指标的快检方法,对不同脱水程度蓖麻油样品进行低场核磁共振(LF-NMR)扫描,结合化学计量学方法,分析弛豫特性指标与脱水蓖麻油样品羟基值、共轭亚油酸和非共轭亚油酸含量的相关性,通过对建模数据、预处理方法和建... 旨在建立一种脱水蓖麻油指标的快检方法,对不同脱水程度蓖麻油样品进行低场核磁共振(LF-NMR)扫描,结合化学计量学方法,分析弛豫特性指标与脱水蓖麻油样品羟基值、共轭亚油酸和非共轭亚油酸含量的相关性,通过对建模数据、预处理方法和建模方法进行优化,建立脱水蓖麻油羟基值、共轭亚油酸和非共轭亚油酸含量预测模型,并对模型的准确性和稳定性进行验证。结果表明:脱水蓖麻油羟基值、共轭亚油酸和非共轭亚油酸含量与弛豫特性中单组分弛豫时间τ_(2w)、弛豫时间τ_(21)和τ_(22)、峰面积S_(21)和S_(22)均呈现良好的线性关系,其相关系数均大于0.96,表明采用LF-NMR技术建立脱水蓖麻油指标的快检方法具有可行性。模型的最佳数据筛选方法为等间隔数4数据波段,最佳数据预处理方法为标准正态变量变换(SNV),最佳建模方法为偏最小二乘法(PLS),该条件下所建立的脱水蓖麻油羟基值、共轭亚油酸和非共轭亚油酸含量模型的预测值与真实值相关性较好,决定系数均大于0.99,预测平均误差为5.61%~7.12%。综上,成功建立了一种脱水蓖麻油指标的快检方法。 展开更多
关键词 lf-nmr 脱水蓖麻油 羟基值 共轭亚油酸 非共轭亚油酸 化学计量学
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Multi-Scale Analysis Combined Operando Elemental/Spectroscopic Measurement Techniques in Oxide-Type All-Solid-State Na Batteries
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作者 Koji Hiraoka Kazuo Yamamoto +2 位作者 Takeshi Kobayashi Tetsuo Sakamoto Shiro Seki 《Energy & Environmental Materials》 2025年第2期34-43,共10页
Understanding the charge/discharge mechanism of batteries plays an important role in the development of high-performance systems,but extremely complicated reactions are involved.Because these complex phenomena are als... Understanding the charge/discharge mechanism of batteries plays an important role in the development of high-performance systems,but extremely complicated reactions are involved.Because these complex phenomena are also bottlenecks for the establishment of all-sol id-state batteries(ASSB),we conducted multi-scale analysis using combined multi-measurement techniques,to directly observe charge/discharge reactions at hierarchical scales for the oxide-type ASSB using Na as the carrier cation.In particular,all of measurement techniques are applied to cross-section ASSB in the same cell,to complementarily evaluate the elemental distributions and structural changes.From Operando scanning electron microscopy-energy-dispersive X-ray spectroscopy,the Na concentration in the electrode layers changes on the micrometer scale under charge/discharge reactions in the first cycle.Furthermore,Operando Raman spectroscopy reveal changes in the bonding states at the atomic scale in the active material,including changes in reversible structural changes.After cycling the ASSB,the elemental distributions are clearly observed along with the particle shapes and can reveal the Na migration mechanism at the nanometer scale,by time-of-flight secondary ion mass spectrometry.Therefore,this study can provide a fundamental and comprehensive understanding of the charge/discharge mechanism by observing reaction processes at multiple scales. 展开更多
关键词 operando oxide-typeall-solid-statebattery Raman SEM-EDS sodium battery TOF-SIMS
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Operando photoelectrochemical analysis of H_(2)O_(2) photoproduction:differentiating catalytic roles of metal nanoclusters and carbon dot-modified nanoclusters
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作者 ZHOU Yanyan LI Zenan +3 位作者 ZHANG Hao WU Yangbo LIAO Fan KANG Zhenhui 《分子科学学报》 2025年第2期3-13,共11页
The photocatalytic production of hydrogen peroxide(H_(2)O_(2))via the oxygen reduction reaction(ORR)holds great significance in chemical engineering,agriculture,and national defense.However,the underlying influence of... The photocatalytic production of hydrogen peroxide(H_(2)O_(2))via the oxygen reduction reaction(ORR)holds great significance in chemical engineering,agriculture,and national defense.However,the underlying influence of interfacial charge dynamics on catalytic performance remains poorly understood due to limitations in conventional characterization techniques.In this study,we employ thiolate-protected gold-silver metal nanoclusters(MNCs)and nitrogen-doped carbon dot-modified nanoclusters(MNCs/N-CDs)as model systems to investigate ORR selectivity and charge dynamics under light irradiation.This catalyst design leverages the self-oxidation behavior of thiolate ligands and the intrinsic ORR selectivity of nanoclusters to establish a clean and well-defined photocatalytic system.By integrating time-resolved transient photovoltage(TPV)spectroscopy and operando transient potential scanning(TPS)test,we demonstrate that N-CDs promote the separation and storage of photoinduced charge carriers,as well as enhance oxygen adsorption and activation on the catalyst surface,thereby significantly improving H_(2)O_(2)production efficiency.These findings offer new mechanistic insights into the interplay between interfacial charge dynamics and photocatalytic performance,providing guidance for the rational design of advanced ORR catalysts. 展开更多
关键词 Oxygen reduction reaction PHOTOCATALYSIS NANOCLUSTERS operando methods
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Perspective on the operando battery monitoring of multi-parameter by embedded optical fiber sensors
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作者 Jun Guo Pengcheng Liu +11 位作者 Fu Xue Jie Zeng Xinyue Mu Feier Wang Zhihan Kong Dingwei Ji Heng Zhou Longbiao Yu Qi Wu Kang Yan Jing Wang Kongjun Zhu 《Journal of Energy Chemistry》 2025年第11期899-919,I0020,共22页
Battery safety has emerged as a critical challenge for achieving carbon neutrality,driven by the increasing frequency of thermal runaway incidents in electric vehicles(EVs)and stationary energy storage systems(ESSs).C... Battery safety has emerged as a critical challenge for achieving carbon neutrality,driven by the increasing frequency of thermal runaway incidents in electric vehicles(EVs)and stationary energy storage systems(ESSs).Conventional battery monitoring technologies struggle to track multiple physicochemical parameters in real time,hindering early hazard detection.Embedded optical fiber sensors have gained prominence as a transformative solution for next-generation smart battery sensing,owing to their micrometer size,multiplexing capability,and electromagnetic immunity.However,comprehensive reviews focusing on their advancements in operando multi-parameter monitoring remain scarce,despite their critical importance for ensuring battery safety.To address this gap,this review first introduces a classification and the fundamental principles of advanced battery-oriented optical fiber sensors.Subsequently,it summarizes recent developments in single-parameter battery monitoring using optical fiber sensors.Building on this foundation,this review presents the first comprehensive analysis of multifunctional optical fiber sensing platforms capable of simultaneously tracking temperature,strain,pressure,refractive index,and monitoring battery aging.Targeted strategies are proposed to facilitate the practical development of this technology,including optimization of sensor integration techniques,minimizing sensor invasiveness,resolving the cross-sensitivity of fiber Bragg grating(FBG)through structural innovation,enhancing techno-economics,and combining with artificial intelligence(AI).By aligning academic research with industry requirements,this review provides a methodological roadmap for developing robust optical sensing systems to ensure battery safety in decarbonization-driven applications. 展开更多
关键词 Battery safety Multi-parameter monitoring Embedded optical fiber sensors operando sensing
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In-situ and operando characterizations in membrane electrode assemblies:Resolving dynamic interfaces and degradation pathways in CO_(2)electrocatalysis
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作者 Jiachen Wu Pengfei Liu Huagui Yang 《Chinese Journal of Catalysis》 2025年第12期1-8,共8页
Membrane electrode assemblies(MEAs)represent the preeminent configuration for industrial-scale CO_(2)electrolysis,yet their dynamic interfaces and degradation pathways remain inadequately resolved.This perspective hig... Membrane electrode assemblies(MEAs)represent the preeminent configuration for industrial-scale CO_(2)electrolysis,yet their dynamic interfaces and degradation pathways remain inadequately resolved.This perspective highlights how advanced operando characterization techniques-synchrotron X-ray spectroscopy,spatially resolved X-ray fluorescence,vibrational spectroscopy,electrochemical diagnostics et al.-decipher atomic-scale catalyst evolution,transient ion/water fluxes,and extreme interfacial microenvironments under industrial current densities.These methodologies reveal critical degradation mechanisms,including catalyst restructuring,carbonate precipitation-driven flooding,and cation-induced pH gradients,which are inaccessible to conventional ex-situ or three-electrode analyses.Integrating multimodal characterization is paramount to correlate transient interfacial chemistry with system-level performance,guiding the rational design of durable,high-selectivity MEAs for scalable CO_(2)conversion. 展开更多
关键词 operando characterization Membrane electrode assemblies Electrocatalytic CO_(2)reduction Interfacial dynamics Degradation pathways
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大豆油煎炸过程理化指标与LF-NMR弛豫特性的相关性研究 被引量:16
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作者 史然 王欣 +2 位作者 刘宝林 卢海燕 赵婷婷 《分析测试学报》 CAS CSCD 北大核心 2013年第6期653-660,共8页
在对大豆油无料/薯条煎炸过程[温度:(180±5)℃,持续36 h]中的酸价(AV)、粘度(V)、吸光值(A)及总极性化合物(TPC)含量等及低场核磁共振(LF-NMR)弛豫特性(峰起始时间T21、T22、T23、相应的峰面积比例S21、S22、S23、单组份弛豫时间T... 在对大豆油无料/薯条煎炸过程[温度:(180±5)℃,持续36 h]中的酸价(AV)、粘度(V)、吸光值(A)及总极性化合物(TPC)含量等及低场核磁共振(LF-NMR)弛豫特性(峰起始时间T21、T22、T23、相应的峰面积比例S21、S22、S23、单组份弛豫时间T2W)变化规律研究的基础上,利用多元回归分析建立了理化指标与其LF-NMR检测结果的相关性模型,并进行验证。结果表明:大豆油的酸价、TPC含量及S21峰面积均随煎炸时间的延长而线性增大,T21、T22峰起始时间及T2W则随煎炸时间的延长而线性减小(r2>0.90),粘度、吸光值随煎炸时间的延长逐渐增加并符合二项式关系(r2>0.90),而T23峰起始时间及S22、S23与煎炸时间之间无明显规律性变化。煎炸薯条后,油样的酸价、粘度、TPC含量、吸光值及S21均较无料煎炸显著增大(P<0.05),而T21、T22峰起始时间及T2W显著缩短。多元回归分析表明,酸价及TPC含量与T2W、T21,粘度与T2W,吸光值与S21间均可建立良好的相关性模型(R2>0.93)。模型验证合理可靠,可通过油样的LF-NMR检测结果有效预测其理化指标的变化。 展开更多
关键词 大豆油 煎炸时间 理化特性 lf-nmr 弛豫特性
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基于低场核磁共振(LF-NMR)弛豫特性的油脂品质检测研究 被引量:12
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作者 赵婷婷 王欣 +1 位作者 卢海燕 刘宝林 《食品工业科技》 CAS CSCD 北大核心 2014年第12期58-65,共8页
研究了低场核磁共振(LF-NMR)检测过程中的仪器参数、检测温度及体积等对大豆油、棕榈油和猪油弛豫特性检测结果的影响,并给出了适用于含固态脂类油脂样品的LF-NMR检测条件,即:TR=2000ms,τ=250μs,EchoCount=6000个,检测体积2.5mL,检测... 研究了低场核磁共振(LF-NMR)检测过程中的仪器参数、检测温度及体积等对大豆油、棕榈油和猪油弛豫特性检测结果的影响,并给出了适用于含固态脂类油脂样品的LF-NMR检测条件,即:TR=2000ms,τ=250μs,EchoCount=6000个,检测体积2.5mL,检测温度50℃。并应用建立的方法对多种地沟油样品进行了检测。结果表明,基于油样的LFNMR弛豫特性,可有效区分8种固态油样和10种液态地沟油,检测正确识别率可达75%和100%,有效避免了假阳性,且S21峰比例面积可有效反映样品的掺杂梯度变化,说明了该方法对固态和液态地沟油也具有较好的识别能力,在后期油脂品质检测应用中具有较好的可行性。 展开更多
关键词 低场核磁共振(lf-nmr) 弛豫特性 参数优化 油脂
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皱皮木瓜真空冻干工艺优化及基于LF-NMR技术的复水特性研究 被引量:16
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作者 崔莉 杜利平 +3 位作者 闫慧娇 刘伟 耿岩玲 王晓 《中国食品学报》 EI CAS CSCD 北大核心 2019年第6期124-133,共10页
目的:对皱皮木瓜片的真空冷冻条件进行优化,研究木瓜片复水过程中水分状态变化。方法:采用单因素试验结合Box-Behnken响应面法,分别以复水比和色差值为指标,考察木瓜片厚度,真空冷冻干燥机的隔板温度以及真空度3个因素对冻干工艺的影响... 目的:对皱皮木瓜片的真空冷冻条件进行优化,研究木瓜片复水过程中水分状态变化。方法:采用单因素试验结合Box-Behnken响应面法,分别以复水比和色差值为指标,考察木瓜片厚度,真空冷冻干燥机的隔板温度以及真空度3个因素对冻干工艺的影响,优化皱皮木瓜片冻干工艺;利用低场核磁共振技术比较真空冷冻干燥和热风干燥的木瓜片成品复水过程中水分状态的变化情况。结果:确定皱皮木瓜真空冷冻干燥的复水比最佳工艺条件:木瓜片厚度4mm,隔板温度40℃,真空度2.4mbar;色差值最优的组合为:木瓜片厚度7.45mm,隔板温度28.37℃,真空度2.02mbar。NMR试验表明,复水过程中进入木瓜片中的水很快转化为不易流动水,结合水和自由水变化不大,且真空冷冻干燥的木瓜片中不易流动水增加较快,说明冻干比热风干燥的木瓜片品质好。结论:本研究结果为优化的皱皮木瓜真空冷冻干燥工艺参数,低场核磁共振技术可用于表征皱皮木瓜复水过程中水分状态的变化。 展开更多
关键词 皱皮木瓜 真空冷冻干燥 lf-nmr(低场核磁共振) 复水特性
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LF-NMR结合化学模式识别鉴别油脂种类及餐饮废弃油脂 被引量:15
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作者 毛锐 王欣 史然 《分析测试学报》 CAS CSCD 北大核心 2017年第3期372-376,共5页
应用主成分分析(Principal component analysis,PCA)和聚类分析法(Cluster analysis,CA)对9种(27个)常见食用植物油及100个餐饮废油的低场核磁共振(Low-field nuclear magnetic resonance,LF-NMR)(T2)弛豫特性数据进行分析。结果表明:... 应用主成分分析(Principal component analysis,PCA)和聚类分析法(Cluster analysis,CA)对9种(27个)常见食用植物油及100个餐饮废油的低场核磁共振(Low-field nuclear magnetic resonance,LF-NMR)(T2)弛豫特性数据进行分析。结果表明:在正常食用油种类区分方面,主成分分析的效果较优,9种食用油在主成分分布图上按种类正确分组,边界清晰。而在正常食用油与餐饮废油的区分方面,聚类分析效果较优,引入30个待测样本后,聚类分析(127个样品,欧式距离=5)的正确率为94.49%,分析误判率为5.51%,分组效果良好。LF-NMR结合化学模式识别可实现对油脂种类及餐饮废弃油脂的鉴别。 展开更多
关键词 低场核磁共振(lf-nmr) 食用油 餐饮废油 主成分分析(PCA) 聚类分析(CA)
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食用/工业明胶的凝胶及LF-NMR弛豫特性的比较 被引量:4
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作者 王欣 郭琦 +2 位作者 黄远芬 谷桂英 刘宝林 《分析测试学报》 CAS CSCD 北大核心 2018年第1期62-69,共8页
该文研究了食品/工业明胶浓度、混合比例及蔗糖或NaCl对体系的黏度、凝冻强度及LF-NMR弛豫特性的影响。结果发现,与食用明胶相比,工业明胶的凝冻强度与黏度较低。随着明胶浓度的增加,体系的黏度、凝胶强度均相对增大;结合水弛豫时间T_(... 该文研究了食品/工业明胶浓度、混合比例及蔗糖或NaCl对体系的黏度、凝冻强度及LF-NMR弛豫特性的影响。结果发现,与食用明胶相比,工业明胶的凝冻强度与黏度较低。随着明胶浓度的增加,体系的黏度、凝胶强度均相对增大;结合水弛豫时间T_(21)、自由水弛豫时间T_(22)及自由水比例S_(22)均减小,而结合水比例S_(21)增大。随着工业明胶含量的增多,混合体系的黏度与凝冻强度均线性降低,T_(21)、T_(22)及S_(21)均线性增大,S_(22)线性减小;相同蔗糖或NaCl浓度下,食用明胶体系的黏度、凝冻强度最大,混合明胶体系次之,而工业明胶体系的最小;随着蔗糖浓度的增加,体系的黏度均增大,食用、混合体系的凝冻强度增大,而工业明胶变化较小;各体系的T_(22)、S_(22)均减小,S_(21)增大,工业明胶的T_(21)增大,而食用明胶、混合明胶体系的T_(21)变化不大。随着NaCl浓度的增加,各体系的凝冻强度均相对降低,而T_(21)、T_(22)、S_(21)均相对增大,S_(22)减小。 展开更多
关键词 明胶 低场核磁共振(lf-nmr) 蔗糖 氯化钠
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无机盐对乙醇-水体系LF-NMR弛豫特性的影响及主成分分析
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作者 刘敏 王欣 刘宝林 《分析测试学报》 CAS CSCD 北大核心 2015年第11期1220-1226,共7页
该文研究了不同浓度(0~9%)的Na Cl,Mg SO4或Na OH对乙醇-水体系LF-NMR弛豫特性的影响,并应用主成分分析(PCA)对样品的弛豫特性进行了分析。研究表明:无机盐种类和浓度会对水及乙醇-水体系的LF-NMR弛豫特性产生影响。无机盐-水二元... 该文研究了不同浓度(0~9%)的Na Cl,Mg SO4或Na OH对乙醇-水体系LF-NMR弛豫特性的影响,并应用主成分分析(PCA)对样品的弛豫特性进行了分析。研究表明:无机盐种类和浓度会对水及乙醇-水体系的LF-NMR弛豫特性产生影响。无机盐-水二元体系仅存在1个弛豫峰,且弛豫时间:Mg SO4〉Na OH〉Na Cl。而无机盐-乙醇-水三元体系则存在2个弛豫峰,Na Cl/Na OH-乙醇-水体系的弛豫峰分别位于200~330 ms和1 300~1 600 ms处;而Mg SO4-乙醇-水体系则位于约250~335 ms和1 620~1 707 ms处。不同种类无机盐、水和乙醇-水体系间的LF-NMR弛豫特性差异均可在PCA得分图上有效反映,且随着无机盐浓度的增加,各浓度梯度在主成分得分图中亦呈规律性分布。说明基于样品的LF-NMR弛豫特性,结合主成分分析法可快速分析无机盐对水/乙醇-水的缔合特性。 展开更多
关键词 低场核磁共振(lf-nmr) 无机盐 乙醇-水体系 弛豫特性
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利用Operando IR-MS研究S Zorb工艺中烯烃反应的影响因素 被引量:3
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作者 袁蕙 徐广通 +4 位作者 史延强 忻睦迪 陈帅 邱丽美 邹亢 《石油学报(石油加工)》 EI CAS CSCD 北大核心 2020年第1期121-129,共9页
设计构建了用于S Zorb反应化学研究的Operando IR-MS分析表征平台,开发了烯烃加氢反应Operando IR-MS表征技术。以炼油厂运行装置使用的S Zorb工业新剂、待生剂及参比剂为对象,以正丁烯为反应探针分子,系统考察了影响烯烃加氢造成辛烷... 设计构建了用于S Zorb反应化学研究的Operando IR-MS分析表征平台,开发了烯烃加氢反应Operando IR-MS表征技术。以炼油厂运行装置使用的S Zorb工业新剂、待生剂及参比剂为对象,以正丁烯为反应探针分子,系统考察了影响烯烃加氢造成辛烷值损失的因素及其规律。结果表明:与新剂相比,待生剂的烯烃相对消耗量大幅减少,其变化趋势与吸附剂中ZnS和碳的质量分数均成负相关;吸附剂表面的活性Ni对加氢和脱硫反应贡献均较大;吸附剂上NixSy的生成及量的增加抑制烯烃的加氢反应。因此,在保证脱硫率前提下为降低汽油的辛烷值损失,可通过抑制吸附剂上过多的活性Ni、选择性调变表面Ni的存在形态、合理控制吸附剂表面ZnS和积炭量等综合方法来实现。 展开更多
关键词 operando IR-MS表征技术 S Zorb吸附脱硫技术 催化剂 烯烃加氢反应 辛烷值损失
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动态现场原位(operando)表征技术在多相催化反应中的应用与进展 被引量:5
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作者 孙杨 丁豆豆 +7 位作者 林昌 刘向林 张超 田鹏飞 曹晨熙 杨子旭 徐晶 韩一帆 《化工进展》 EI CAS CSCD 北大核心 2019年第1期260-277,共18页
动态现场原位(operando)表征是在接近过程工业反应条件下,揭示催化反应机理及工业催化剂结构演变的新兴动态结构解析技术。本文综述了operando表征技术在多相催化反应中的应用及发展趋势,从operando红外、operando拉曼、operando X射线... 动态现场原位(operando)表征是在接近过程工业反应条件下,揭示催化反应机理及工业催化剂结构演变的新兴动态结构解析技术。本文综述了operando表征技术在多相催化反应中的应用及发展趋势,从operando红外、operando拉曼、operando X射线衍射、operando穆斯堡尔谱、operando X射线吸收谱及operando X射线光电子能谱6个方面概述了operando技术的最新进展。此外,还介绍了正在兴起的operando联用技术,该技术综合多种operando技术为一体,能够在反应过程中对催化剂的结构全貌进行深度表征,实现工业催化剂的理性设计,将成为未来多相催化研究的重要手段。然而,目前operando技术的时间分辨率和空间分辨率仍需进一步提升,其巨大潜力依然有待开发。 展开更多
关键词 动态现场原位技术 催化 原位表征 催化剂构-效关系 反应 表面
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Local structural evolutions of CuO/ZnO/Al2O3 catalyst for methanol synthesis under operando conditions studied by in situ quick X-ray absorption spectroscopy 被引量:4
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作者 Xue-Ping Sun Fan-Fei Sun +5 位作者 Song-Qi Gu Jing Chen Xian-Long Du Jian-Qiang Wang Yu-Ying Huang Zheng Jiang 《Nuclear Science and Techniques》 SCIE CAS CSCD 2017年第2期35-43,共9页
In situ quick X-ray absorption spectroscopy(QXAFS) at the Cu and Zn K-edge under operando conditions has been used to unravel the Cu/Zn interaction and identify possible active site of CuO/ZnO/Al_2O_3 catalyst for met... In situ quick X-ray absorption spectroscopy(QXAFS) at the Cu and Zn K-edge under operando conditions has been used to unravel the Cu/Zn interaction and identify possible active site of CuO/ZnO/Al_2O_3 catalyst for methanol synthesis. In this work, the catalyst, whose activity increases with the reaction temperature and pressure, was studied at calcined, reduced, and reacted conditions. TEM and EDX images for the calcined and reduced catalysts showed that copper was distributed uniformly at both conditions. TPR profile revealed two reduction peaks at 165 and 195 °C for copper species in the calcined catalyst. QXAFS results demonstrated that the calcined form consisted mainly of a mixed Cu O and Zn O, and it was progressively transformed into Cu metal particles and dispersed Zn O species as the reduction treatment. It was demonstrated that activation of the catalyst precursor occurred via a Cu^+intermediate, and the active catalyst predominantly consisted of metallic Cu and Zn O evenunder higher pressures. Structure of the active catalyst did not change with the temperature or pressure, indicating that the role of the Zn was mainly to improve Cu dispersion.This indicates the potential of QXAFS method in studying the structure evolutions of catalysts in methanol synthesis. 展开更多
关键词 In SITU Quick X-ray ABSORPTION spectroscopy CuO/ZnO/Al2O3 CATALYST operando condition
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Operando X-ray diffraction analysis of the degradation mechanisms of a spinel LiMn2O4 cathode in different voltage windows 被引量:2
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作者 Fakui Luo Congcong Wei +6 位作者 Chi Zhang Hui Gao Jiazheng Niu Wensheng Ma Zhangquan Peng Yanwen Bai Zhonghua Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第5期138-146,共9页
The understanding of reaction mechanisms of electrode materials is of significant importance for the development of advanced batteries.The LiMn2O4 cathode has a voltage plateau around 2.8 V(vs.Li^+/Li),which can provi... The understanding of reaction mechanisms of electrode materials is of significant importance for the development of advanced batteries.The LiMn2O4 cathode has a voltage plateau around 2.8 V(vs.Li^+/Li),which can provide an additional capacity for Li storage,but it suffers from a severe capacity degradation.In this study,operando X-ray diffraction is carried out to investigate the structural evolutions and degradation mechanisms of LiMn2O4 in different voltage ranges.In the range of 3.0-4.3 V(vs.Li^+/Li),the LiMn2O4 cathode exhibits a low capacity but good cycling stability with cycles up to 100 cycles and the charge/discharge processes are associated with the reversible extraction/insertion of Li^+from/into LixMn2O4(0≤x≤1).In the range of 1.4-4.4 V(vs.Li^+/Li),a capacity higher than 200 mAh/g is achieved,but it rapidly decays during the cycling.The voltage plateau around 2.8 V(vs.Li^+/Li)is related to the transformation of the cubic LiMn2O4 phase to the tetragonal Li2Mn2O4 phase,which leads to the formation of cracks as well as the performance degradation. 展开更多
关键词 LITHIUM-ION BATTERY OVER-DISCHARGE Phase transition CATHODE operando X-ray DIFFRACTION
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In-situ/operando characterization techniques in lithium-ion batteries and beyond 被引量:8
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作者 Haoyu Li Shaohua Guo Haoshen Zhou 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第8期191-211,I0005,共22页
Nowadays,in-situ/operando characterization becomes one of the most powerful as well as available means to monitor intricate reactions and investigate energy-storage mechanisms within advanced batteries.The new applica... Nowadays,in-situ/operando characterization becomes one of the most powerful as well as available means to monitor intricate reactions and investigate energy-storage mechanisms within advanced batteries.The new applications and novel devices constructed in recent years are necessary to be reviewed for inspiring subsequent studies.Hence,we summarize the progress of in-situ/operando techniques employed in rechargeable batteries.The members of this large family are divided into three sections for introduction,including bulk material,electrolyte/electrode interface and gas evolution.In each part,various energy-storage systems are mentioned and the related experimental details as well as data analysis are discussed.The simultaneous strategies of various in-situ methods are highlighted as well.Finally,current challenges and potential solutions are concluded towards the rising influence and enlarged appliance of in-situ/operando techniques in the battery research. 展开更多
关键词 In-situ/operando Characterization techniques Secondary batteries
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Thickness evolution of graphite-based cathodes in the dual ion batteries via in operando optical observation 被引量:1
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作者 Na Li Yaoda Xin +4 位作者 Haosen Chen Shuqiang Jiao Hanqing Jiang Wei-Li Song Daining Fang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第2期122-128,共7页
Graphite has been currently considered as a promising cathode material in dual ion batteries(DIBs)due to its unique features of sp2 hybridized carbon and stacked two-dimensional layered structures.However,unexpected v... Graphite has been currently considered as a promising cathode material in dual ion batteries(DIBs)due to its unique features of sp2 hybridized carbon and stacked two-dimensional layered structures.However,unexpected volume/thickness changes in the graphite cathodes,induced by the intercalation/deintercalation of anions with large molecular size have been known to be a critical problem in designing DIB cells.To understand the volume/thickness changes in the DIB electrodes,in operando optical observing apparatus has been employed to observe the cross-section view of a graphite-based cathode upon cycles in the present work.The observation suggests that the cathode initially presented a huge irreversible thickness change(60%),and such thickness variation was prone to reduce and remain <20% in the following cycles.The results from both in operando observation and electrochemical characterizations collectively indicate that the greater thickness variation at initial cycle should be attributed to both anion intercalation into graphite-based cathodes and irreversible decomposition of chemical components in the DIB system.The method here highlights a universal route for fundamentally understanding the electrodes of huge volume variation. 展开更多
关键词 DUAL ion BATTERIES In operando optical observation GRAPHITE CATHODE Thickness EVOLUTION
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Rapid operando gas monitor for commercial lithium ion batteries: Gas evolution and relation with electrode materials 被引量:9
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作者 Siqi Lyu Na Li +3 位作者 Lei Sun Shuqiang Jiao Haosen Chen Wei-Li Song 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第9期14-25,I0002,共13页
Internal gases caused by side reactions are crucial signals for evaluating health and safety states of Li-ion batteries(LIBs)while it is still a great challenge to timely realize accurate monitoring.To address the iss... Internal gases caused by side reactions are crucial signals for evaluating health and safety states of Li-ion batteries(LIBs)while it is still a great challenge to timely realize accurate monitoring.To address the issues of implanting various gas sensors into commercial batteries,here a novel method is developed to fast operando monitoring gas evolution via equipping non-dispersive infrared multi-gases sensors into a sealed tank,where real commercial batteries with one open end could be settled for operating.The generated CO_(2)concentration is strongly linked with both voltage and temperature,while the concentrations of CH_(4) and C_(2)H_(4) are solely dependent on temperature.As a typical trace gas,evolution behaviors of CO_(2)have been related to 0_(2) generation from LiNi_(o.5)Mn_(0.3)CoO_(2)0_(2) positive electrode,implying stable CO_(2)release below a critical voltage of 4.5 V.By tracking CO_(2)concentration,an increased amount of Li_(2)CO_(3) was monitored on the surface of graphite negative electrode during discharge process at dfferent temperatures and cutoff voltages,which contributes to the component variation of solid electrolyte interfaces.Such operando techniques promise a plaform for well understanding the interaction of side reactions linked with gas evolution between positive and negative electrodes in commercial LIBs. 展开更多
关键词 operando monitoring CO_(2)evolution Fast response Li-ion batteries
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Simultaneously mastering operando strain and reconstruction effects via phase-segregation strategy for enhanced oxygen-evolving electrocatalysis 被引量:2
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作者 Daqin Guan Chenliang Shi +6 位作者 Hengyue Xu Yuxing Gu Jian Zhong Yuchen Sha Zhiwei Hu Meng Ni Zongping Shao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第7期572-580,I0012,共10页
Material strain and reconstruction effects are critical for catalysis reactions,but current insights into operando strain effects during reaction and means to master catalyst reconstruction are still lacking.Here,we p... Material strain and reconstruction effects are critical for catalysis reactions,but current insights into operando strain effects during reaction and means to master catalyst reconstruction are still lacking.Here,we propose a facile thermal-induced phase-segregation strategy to simultaneously master material operando strain and reconstruction effects for enhanced oxygen-evolving reaction(OER).Specifically,self-assembled and controllable layered LiCoO_(2)phase and Co_(3)O_(4)spinel can be generated from pristine Li2Co_(2)O_(4)spinel via Li and O volatilization under different temperatures,realizing controllable proportions of two phases by calcination temperature.Combined operando and ex-situ characterizations reveal that obvious tensile strain along(003)plane appears on layered LixCoO_(2)phase during OER,while low-valence Co_(3)O_(4)phase transforms into high-valence CoOOHx,realizing simultaneous operando strain and reconstruction effects.Further experimental and computational investigations demonstrate that both strained LixCoO_(2)phase and reconstructed CoOOHxcompound contribute to the beneficial adsorption of important OH-reactants,while respective roles in activity and stability are uncovered by exploring their latticeoxygen participation mechanism.This work not only reveals material operando strain effects during OER,but also inaugurates a new thermal-induced phase-segregation strategy to artificially master material operando strain and reconstruction effects,which will enlighten rational material design for many potential reactions and applications. 展开更多
关键词 operando strain Structural reconstruction Phase-segregation strategy operando synergistic effects Oxygen-evolving reaction
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In situ and operando infrared spectroscopy of battery systems:Progress and opportunities 被引量:3
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作者 Murilo M.Amaral Carla G.Real +4 位作者 Victor Y.Yukuhiro Gustavo Doubek Pablo S.Fernandez Gurpreet Singh Hudson Zanin 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第6期472-491,I0011,共21页
In situ and operando infrared spectroscopies are powerful techniques to support the design of novel materials for batteries and the development of new battery systems.These techniques can support the study of batterie... In situ and operando infrared spectroscopies are powerful techniques to support the design of novel materials for batteries and the development of new battery systems.These techniques can support the study of batteries by identifying the formation of new species and monitoring electrochemical energy stability.However,few works have employed these techniques,which can be used to investigate various materials,including systems beyond lithium-ion technology,in the research of batteries.Therefore,this review presents a comprehensive overview focusing on the main contributions of in situ and operando infrared spectroscopy for lithium-ion batteries(LIBs)and other battery systems.These techniques can successfully identify the formation of species during the electrolyte reduction,electrode degradation,and the formation of the solid-electrolyte interphase(SEI)layer.From these outcomes,it is possible to conclude that this characterization approach should be employed as a protocol to overcome remaining issues in batteries,consequently supporting battery research.This review aims to be a guide on how infrared spectroscopy can contribute to monitoring battery systems and to lead researchers interested in applying this technique. 展开更多
关键词 In situ spectroscopy operando spectroscopy FTIR Spectro-electrochemical cells BATTERIES
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