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Probing On-Surface chemistry at the Nanoscale Using Tip-Enhanced Raman Spectroscopy

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CCS chemistry 2023年第1期5卷 55-71页

作者： Zhen-Feng Cai Naresh Kumar Renato Zenobi Department of Chemistry and Applied Biosciences ETH ZurichZurich CH-8093

chemistry on solid surfaces is central to many research areas of practical interest,such as synthesis,catalysis,electrochemistry,photochemistry,and materials science.A comprehensive understanding of the nanoscale on-surface chemistry involved in these areas is important for establishing composition-structure-performance relationships.With the rapid development of tip-enhanced Raman spectroscopy(TERS),it has become possible to investigate physical and chemical processes on suitable surfaces at the nanoscale level and in real space.In this review,after a brief introduction of the background of onsurface chemistry and TERS,we systematically discuss the progress in the application of TERS in this field.Our focus is the applications of TERS to nanoscale coordination processes,decomposition reactions,polymerization processes,electrochemical reactions,catalytic chemistry,and functionalization chemistry on solid surfaces.We conclude by discussing the future challenges and development of TERS techniques and related applications in on-surface chemistry.

关键词： on-surface chemistry tip-enhanced Raman spectroscopy scanning probe microscopy chemical imaging nanoscale chemical analysis spatial resolution

Gelation of polymeric nanoparticles

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Particuology 2014年第3期12卷 1-11页

作者： Hua Wu Massimo Morbidelli Institute for Chemical and Bioengineering.Department of Chemistry and Applied Biosciences ETH Zurich8093 ZurichSwitzerland

We review how, starting from polymeric nanoparticles, to generate clusters of fractal morphology and to expand the entire space and interconnect to form gels, through either Brownian motion or intense shear-induced aggregation. In the case of Brownian motion-induced gelation, specific techniques developed to obtain uniform structure of gels under both reaction-limited and diffusion-limited cluster aggregation conditions have been described. In the case of intense shear-induced gelation as a newly developed technique, our focus is on its principle, theoretical development and advantages with respect to Brownian motion-induced gelation in practical applications. We consider gelation of both rigid and soft particles. As a physical process, the bonding between the particles within gels is owed to van der Waals attractions, thus being easily broken. However, in the case of soft particles that can coalesce upon contact, the coalescence can allow the particles to stick together forming permanent gels. In this case, the gel structure can be controlled by controlling the degree of coalescence. Techniques used to control the degree of coalescence have also been described.

关键词： Structured material Fractal Gelation Gel Polymer

Spectroscopic visualization of hydrogenation and hydrogen diffusion on a bimetallic interface with high spatial resolution

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Spectroscopic visualization of hydrogenation and hydrogen di...

Tough PEG-only hydrogels with complex 3D structure enabled by digital light processing of“all-PEG”resins

第二十届全国光散射学术会议（CNCLS20）

作者： Hao Yin Liqing Zheng Wei Fang Ying-hung Lai Nikolaus Porenta Guillaume Goubert Jeremy Richardson Bin Ren Jianfeng Li Renato Zenobi Department of Chemistry and Applied Biosciences ETH Zurich department of chemistry Xiamen University

＜正＞Catalytic hydrogenation has diverse important industrial uses.Most frequently,industrial hydrogenation relies on heterogeneous catalysts especially novel metal hydrogenation catalysts such as palladium （Pd）,platinum （Pt）,ruthenium （Ru）.While a single metal catalyst is not enough to achieve both high efficiency and selectivity,researchers have developed several

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Aggregate 2023年第6期4卷 57-70页

作者： Safira Noor Anindita Riccardo Conti Doris Zauchner Nevena Paunovi´c Wanwan Qiu Marina Green Buzhor Adva Krivitsky Zhi Luo Ralph Müller Hansjörg Grützmacher Xiao-Hua Qin Jean-Christophe Leroux Yinyin Bao Department of Chemistry and Applied Biosciences Institute of Pharmaceutical SciencesETH ZurichZunichSwitzerland Laboratory of Inorganic Chemitry Department of Chemistry and Applied BiosciencesETH ZurichZurichSwitzerland department of Health Sciences and Technology Institute for BiomechanicsETH ZurichZurichSwitzerland

Digital light processing(DLP)of structurally complex poly(ethylene glycol)(PEG)hydrogels with high mechanical toughness represents a long-standing challenge in theﬁeld of 3D printing.Here,we report a 3D printing approach for the high-resolution manufacturing of structurally complex and mechanically strong PEG hydrogels via heat-assisted DLP.Instead of using aqueous solutions of photo-crosslinkable monomers,PEG macromonomer melts wereﬁrst printed in the absence of water,resulting in bulk PEG networks.Then,post-printing swelling of the printed networks was achieved in water,producing high-ﬁdelity 3D hydrogels with complex structures.By employing a dual-macromonomer resin containing a PEG-based four-arm macrophotoinitiator,“all-PEG”hydrogel constructs were pro-duced with compressive toughness up to 1.3 MJ m^(-3).By this approach,porous 3D hydrogel scaffolds with trabecular-like architecture were fabricated,and the scaf-fold surface supported cell attachment and the formation of a monolayer mimicking bone-lining cells.This study highlights the promises of heat-assisted DLP of PEG photopolymers for hydrogel fabrication,which may accelerate the development of 3D tissue-like constructs for regenerative medicine.

关键词： 3D printing digital light processing PEG hydrogels

超细纤维素纳米晶增强MXene仿生复合材料的多功能电磁屏蔽性能

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Science China Materials 2023年第4期66卷 1597-1606页

作者：吴娜李宾潘飞张如娜刘久荣曾志辉 Department of Chemistry and Applied Biosciences ETH ZurichCH-8093 ZurichSwitzerland Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials Ministry of Education and School of Materials Science and EngineeringShandong UniversityJinan 250061China department of chemistry University of BaselMattenstrasse 24aBPR 1096BaselSwitzerland

聚合物用于改善过渡金属碳化物和/或氮化物(MXenes)的力学性能、构建高性能电磁(EMI)屏蔽结构面临以下挑战:绝缘聚合物对MXene基复合材料导电性和电磁屏蔽性能的影响以及聚合物的不可再生性.本文将一维、超细、可持续的纤维素纳米晶体(C... 详细信息

聚合物用于改善过渡金属碳化物和/或氮化物(MXenes)的力学性能、构建高性能电磁(EMI)屏蔽结构面临以下挑战:绝缘聚合物对MXene基复合材料导电性和电磁屏蔽性能的影响以及聚合物的不可再生性.本文将一维、超细、可持续的纤维素纳米晶体(CNCs)用于增强MXene纳米片,从而制备出高强度、高柔性、同时兼顾优异导电性和电磁屏蔽效能(SE)的仿生复合材料,其性能优于目前报道的聚合物复合材料.在厚度仅为2–14μm的情况下,MXene/CNC纳米复合材料的电磁屏蔽效能分别达到30–66 d B,比屏蔽效能和面比屏蔽效能分别达到15,155 d B mm^(-1)和54,125 d B cm^(2)g^(-1).复合薄膜具有良好的光热性能,扩展了其应用场景.结合简便、高效、可规模化的常压干燥制备方法得到的超薄、柔韧、高强度、多功能的CNC增强MXene基仿生薄膜在下一代先进电子或航空航天领域显示出巨大的应用潜力.

关键词：仿生复合材料纤维素纳米晶体聚合物复合材料纳米复合材料常压干燥电磁屏蔽性能屏蔽效能过渡金属碳化物

HIGH-PERFORMANCE COMPUTATION AND ARTIFICIAL INTELLIGENCE IN PESTICIDE DISCOVERY: STATUS AND OUTLOOK

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Frontiers of Agricultural Science and Engineering 2022年第1期9卷 150-154页

作者： Li ZHANG Jialin CUI Qi HE Qing X.LI Innovation Center of Pesticide Research Department of Applied ChemistryCollege of ScienceChina Agricultural UniversityBeijing 100193China department of Molecular biosciences and Bioengineering University of Hawaii at ManoaHonoluluHI 96822USA

1 INTRODUCTION Pesticides are extremely important in global crop,food and ecological safety.Use of pesticides can prevent around 20%to 30%of global crop loss every year.The continuous growth of population and the limited acreage of agricultural land require increasing crop yields to feed people.Pesticides are important for protecting crops and preventing yield losses.With the increasing concerns over environmental protection,ecofriendly pesticides are needed to replace some higher risk ones.It is slow and difficult to successfully discover new pesticides with the standard random screening.New technologies and methods,such as high-performance computation and artificial intelligence(AI),can dramatically facilitate in the pesticide discovery process.

关键词： artificial pesticides PEST

In situ frequency gating and beam splitting of vacuum- and extreme-ultraviolet pulses

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Light(Science & Applications) 2016年第1期5卷 396-402页

作者： Rajendran Rajeev Johannes Hellwagner Anne Schumacher Inga Jordan Martin Huppert Andres Tehlar Bhargava Ram Niraghatam Denitsa Baykusheva Nan Lin Aaron von Conta Hans Jakob Wörner Laboratory of Physical chemistry Department of Chemistry and Applied BiosciencesVladimir-Prelog-Weg 2ETH ZurichZurich 8093Switzerland

Monochromatization of high-harmonic sources has opened fascinating perspectives regarding time-resolved photoemission from all phases of matter.Such studies have invariably involved the use of spectral filters or spectrally dispersive optical components that are inherently lossy and technically complex.Here we present a new technique for the spectral selection of near-threshold harmonics and their spatial separation from the driving beams without any optical elements.We discover the existence of a narrow phase-matching gate resulting from the combination of the non-collinear generation geometry in an extended medium,atomic resonances and absorption.Our technique offers a filter contrast of up to 104 for the selected harmonics against the adjacent ones and offers multiple temporally synchronized beamlets in a single unified scheme.We demonstrate the selective generation of 133,80 or 56 nm femtosecond pulses from a 400-nm driver,which is specific to the target gas.These results open new pathways towards phase-sensitive multi-pulse spectroscopy in the vacuum-and extreme-ultraviolet,and frequencyselective output coupling from enhancement cavities.

关键词： beam splitting below-threshold harmonics coherent extreme-ultraviolet pulses frequency gating non-collinear generation

Breath Metabolomics using Secondary Electrospray Ionization(SESI)-High Resolution Mass Spectrometry

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Breath Metabolomics using Secondary Electrospray Ionization(...

介于二维和三维晶体间的超薄晶态材料的X射线衍射及对称性研究

2018年中国质谱学术大会（CMSC2018）

作者： Renato Zenobi College of chemistry & Chemical Engineering Xiamen University Department of Chemistry and Applied Biosciences ETH Zurich

On-line breath analysis is a powerful approach to obtain insight into the metabolism of a person in real time. With ambient ionization methods, this can be achieved rapidly and completely non-invasively, opening up interesting possibilities to diagnose diseases via exhaled breath, to discern diurnal changes in the metabolism, and to monitor drug use(or drug abuse) by analyzing the chemical composition of exhaled breath. Our laboratory uses SESI coupled to high-resolution MS for this purpose, which affords sub-ppt limits of detection, and analysis and identification [1] of compounds with molecular weights up to 1000 Da. This keynote lecture will present several examples for application of SESI-MS in medical diagnosis, including the detection of novel biomarkers for respiratory diseases such as obstructive sleep apnea(OSA) [2], chronic obstructive pulmonary disease(COPD) [3], pulmonary fibrosis, and asthma. Monitoring of drug compliance and pharmacokinetics [4] via real-time SESI-MS will also be shown. A variety of biomarkers that describe diseases have been detected in exhaled breath and identified via SESI-MS. Identification is normally aided by chromatographic separation of exhaled breath condensate and comparison against commercially available or synthetic reference compounds.

关键词： Secondary Electrospray Ionization On-line Exhaled Breath Analysis Medical Diagnosis

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Science Bulletin 2023年第9期68卷 887-891,M0003页

作者：马恒瑞蒋巧荣南子昂李根贾艳艳宁若昕吉家葆曹振明吕林喆李慧齐戴升林海昕谢兆雄 State Key Laboratory of Physical chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy Materialsand Department of ChemistryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center Institute of Fine ChemicalsSchool of Chemistry&Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China Department of Chemistry and Applied Biosciences Laboratory of Physical ChemistryETH ZürichZürich CH-8093Switzerland Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKKEM) Xiamen 361005China

为了深入理解超薄晶态材料的结构和对称性的独特性,本文在充分考虑超薄晶态材料堆积自由度的情况下,从数学和晶体学角度对介于二维与三维之间的超薄纳米晶体的对称性和X射线衍射进行了探讨.认为超薄纳米晶体的对称性需要用数学层群(laye... 详细信息

为了深入理解超薄晶态材料的结构和对称性的独特性,本文在充分考虑超薄晶态材料堆积自由度的情况下,从数学和晶体学角度对介于二维与三维之间的超薄纳米晶体的对称性和X射线衍射进行了探讨.认为超薄纳米晶体的对称性需要用数学层群(layer group)来描述;另外,由于其层堆叠方向上不具有周期性结构,超薄纳米晶体可能产生特异衍射特征.为了验证这一观点,研究了三类在层堆叠方向不具有周期性的典型超薄纳米晶体的X射线衍射,从实验上观察到了超薄纳米晶体与其体相三维晶体粉末X射线衍射的不同;针对基于三维晶体的X射线衍射模拟软件不再适用于超薄纳米晶体的情况,发展了超薄纳米晶体的全结构X射线衍射分析方法,很好地模拟了超薄纳米晶粉末X射线衍射图.该研究对超薄纳米晶态材料的结构及对称性提出了新见解,将有益于推动相关材料的构效关系研究和新功能开发.

关键词：纳米晶体周期性结构 X射线衍射纳米晶粉末模拟软件对称性自由度