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Photo-responsive functional materials based on light-driven molecular motors

Light(science & Applications) 2024年第3期13卷 407-420页

作者： Yanping Deng Guiying Long Yang Zhang Wei Zhao Guofu Zhou Ben L.Feringa Jiawen Chen SCNU-UG International Joint Laboratory of Molecular science and Displays National Center for International Research on Green OptoelectronicsSouth China Normal UniversityGuangzhou 510006China Stratingh Institute for Chemistry University of GroningenNijenborgh 49747AG GroningenThe Netherlands

In the past two decades,the research and development of light-triggered molecular machines have mainly focused on developing molecular devices at the nanoscale.A key scientific issue in the field is how to amplify the controlled motion of molecules at the nanoscale along multiple length scales,such as the mesoscopic or the macroscopic scale,or in a more practical perspective,how to convert molecular motion into changes of properties of a macroscopic ***-driven molecular motors are able to perform repetitive unidirectional rotation upon irradiation,which offers unique opportunities for responsive macroscopic *** several reviews that focus on the design,synthesis and operation of the motors at the nanoscale,photo-responsive macroscopic materials based on light-driven molecular motors have not been comprehensively *** the present review,we first discuss the strategy of confining absolute molecular rotation into relative rotation by grafting motors on ***,examples of self-assemble motors in supramolecular polymers with high internal order are ***,we will focus on building of motors in a covalently linked system such as polymeric gels and polymeric liquid crystals to generate complex responsive ***,a perspective toward future developments and opportunities is *** review helps us getting a more and more clear picture and understanding on how complex movement can be programmed in light-responsive systems and how man-made adaptive materials can be invented,which can serve as an important guideline for further design of complex and advanced responsive materials.

关键词： functions materials material

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Dynamic Control of Multiple Optical Patterns of Cholesteric Liquid Crystal Microdroplets by Light-Driven Molecular Motors

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CCS Chemistry 2024年第2期6卷 427-438页

作者： Jiaqin Li Shuting Xie Jiahui Meng Yuying Liu Qi Zhan Yang Zhang Lingling Shui Guofu Zhou Ben L.Feringa Jiawen Chen SCNU-UG International Joint Laboratory of Molecular science and Displays National Center for International Research on Green OptoelectronicsSouth China Normal UniversityGuangzhou 510006 Joint Laboratory of Optofluidic Technology and Systems Guangdong Provincial Key Laboratory of Nanophotonic Functional Materials and DevicesSchool of Information and Optoelectronic Science and EngineeringSouth China Normal UniversityGuangzhou 510006 Stratingh Institute for Chemistry University of Groningen9747AG Groningen

The key to high-level encryption and anti-counterfeiting techniques is the storage of multiple levels of distinct information that can be individually and precisely addressed by certain *** continues to be a formidable challenge as the concealed images or codes must be read with fast response and high resolution without cross-talk to the first layer of ***,we report a non-fluorescencebased strategy to establish responsive encryption labels taking advantage of solely tuning multiple optical patterns of cholesteric liquid crystal(CLC)microdroplets doped with light-driven molecular *** photo-triggered unidirectional rotation of the motor induced not only changes in the helical twist power value but the opposite helical orientation of the superstructure in CLCs as well,resulting in changes in both the structural color and the selective reflection of circularly polar *** designed labels,which featured highly selective addressability of dual-level distinct information,good reversibility,and viewing angle-independence,were applied to build devices for daily practical use,demonstrating great potential in anti-counterfeiting technology and provide a versatile platform for enhanced data protection and encryption of authentic information.

关键词： molecular motor chirality amplification cholesteric liquid crystal anti-counterfeiting label data encryption

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Stability and activity of carbon nanofiber-supported catalysts in the aqueous phase reforming of ethylene glycol

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Journal of Energy Chemistry 2013年第2期22卷 257-269页

作者： T. van Haasterecht C. C. I. Ludding K. P. de Jong J. H. Bitter Inorganic Chemistry and Catalysis Utrecht University

Nickel, cobalt, copper and platinum nanoparticles supported on carbon nano-fibers were evaluated with respect to their stability, catalytic activity and selectivity in the aqueous phase reforming of ethylene glycol （230 ℃, autogenous pressure, batch reactor）. The initial surface-specific activities for ethylene glycol reforming were in a similar range but decreased in the order of Pt （15.5 h-1 ）〉Co（13.0 h 1 ）〉Ni（5.2 h-1） while the Cu catalyst only showed low dehydrogenation activity. The hydrogen molar selectivity decreased in the order of Pt （53%）〉Co（21%）〉Ni （15%） as a result of the production of methane over the latter two catalysts. Over the Co catalyst acids were formed in the liquid phase while alcohols were formed over Ni and Pt. Due to the low pH of the reaction mixture, especially in the case of Co （as a result of the formed acids）, significant cobalt leaching occurs which resulted in a rapid deactivation of this catalyst. Investigations of the spent catalysts with various techniques showed that metal particle growth is responsible for the deactivation of the Pt and Ni catalysts. In addition, coking might also contribute to the deactivation of the Ni catalyst.

关键词： carbon nano-fiber catalyst deactivation aqueous phase reforming non-noble metal catalyst

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Effect of initial nickel particle size on stability of nickel catalysts for aqueous phase reforming

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Journal of Energy Chemistry 2016年第2期25卷 287-294页

作者： Tomas van Haasterecht Marten Swart Krijn P.de Jong Johannes Hendrik Bitter Inorganic Chemistry and Catalysis Utrecht University 3508 TB Utrecht The Netherlands Biobased Chemistry and Technology Wageningen University 6708 WG Wageningen The Netherlands

The deactivation behavior by crystallite growth of nickel nanoparticles on various supports（carbon nanofibers, zirconia, Si C, α-Al2O3 and γ-Al2O3） was investigated in the aqueous phase reforming of ethylene glycol. Supported Ni catalysts of ~10 wt% were prepared by impregnation of carbon nanofibers（CNF）,Zr O2, SiC, γ-Al2O3 and α-Al2O3. The extent of the Ni nanoparticle growth on various support materials follows the order CNF ~ ZrO2〉 SiC 〉 γ-Al2O3〉〉 α-Al2O3 which sequence, however, was determined by the initial Ni particle size. Based on the observed nickel leaching and the specific growth characteristics; the particle size distribution and the effect of loading on the growth rate, Ostwald ripening is suggested to be the main mechanism contributing to nickel particle growth. Remarkably, initially smaller Ni particles（~12 nm） supported on α-Al2O3 were found to outgrow Ni particles with initially larger size（~20 nm）. It is put forward that the higher susceptibility with respect to oxidation of the smaller Ni nanoparticles and differences in initial particle size distribution are responsible for this behavior.

关键词： Aqueous phase reforming Particle growth Catalyst stability Ostwald ripening Leaching Nickel catalysts Particle size effect Support effect

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Understanding and tuning blue-to-near-infrared photon cutting by the Tm^(3+)/Yb^(3+) couple

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Light(science & Applications) 2020年第1期9卷 992-1000页

作者： Dechao Yu Ting Yu Arnoldus Jvan Bunningen Qinyuan Zhang Andries Meijerink Freddy T.Rabouw Debye Institute for Nanomaterials science Utrecht UniversityPrincetonplein 13584 CC UtrechtThe Netherlands State Key Laboratory of Luminescence Materials and Devices Institute of Optical Communication MaterialsSouth China University of TechnologyGuangzhou 510641China

Lanthanide-based photon-cutting phosphors absorb high-energy photons and‘cut’them into multiple smaller excitation *** quanta are subsequently emitted,resulting in photon-conversion efficiencies exceeding *** photon-cutting process relies on energy transfer between optically active lanthanide ions doped in the ***,it is not always easy to determine,let alone predict,which energy-transfer mechanisms are operative in a particular *** makes the identification and design of new promising photon-cutting phosphors *** we unravel the possibility of using the Tm^(3+)/Yb^(3+) lanthanide couple for photon *** compare the performance of this couple in four different host *** energy transfer from Tm^(3+)to Yb^(3+) would enable blue-to-near-infrared conversion with 200% ***,we identify phonon-assisted cross-relaxation as the dominant Tm^(3+)-to-Yb^(3+) energy-transfer mechanism in YBO_(3),YAG,and Y_(2)O_(3).In NaYF_(4),in contrast,the low maximum phonon energy renders phonon-assisted cross-relaxation impossible,making the desired cooperative mechanism the dominant energy-transfer *** work demonstrates that previous claims of high photon-cutting efficiencies obtained with the Tm^(3+)/Yb^(3+) couple must be interpreted with ***,the Tm^(3+)/Yb^(3+) couple is potentially promising,but the host material-more specifically,its maximum phonon energy-has a critical effect on the energy-transfer mechanisms and thereby on the photon-cutting performance.

关键词： couple phonon lanthanide

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Extending the dynamic temperature range of Boltzmann thermometers

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Light(science & Applications) 2022年第12期11卷 3069-3079页

作者： Thomas Pieter van Swieten Jesse Merlijin Steenhoff Auke Vlasblom Ravi de Berg Sam Pieter Mattern Freddy Teunis Rabouw Markus Suta Andries Meijerink Debye Institute for Nanomaterials science Utrecht UniversityPrincetonplein 13584 CC UtrechtThe Netherlands Inorganic Photoactive Materials Heinrich Heine University DüsseldorfUniversitätsstraBe 140225 DüsseldorfGermany

Lanthanide-doped(nano)crystals are an important class of materials in luminescence *** working mechanism of these thermometers is diverse but most often relies on variation of the ratio of emission intensities from two thermally coupled excited states with *** low temperatures,nonradiative coupling between the states can be slow compared to radiative decay,but,at higher temperatures,the two states reach thermal equilibrium due to faster nonradiative *** thermal equilibrium,the intensity ratio follows Boltzmann statistics,which gives a convenient model to calibrate the ***,we investigate multiple strategies to shift the onset of thermal equilibrium to lower temperatures,which enables Boltzmann thermometry in a wider dynamic *** use Eu^(3+)-doped microcrystals as a model system and find that the nonradiative coupling rates increase for host lattices with higher vibrational energies and shorter lanthanide-ligand distances,which reduces the onset temperature of thermal equilibrium by more than 400 *** additionally reveal that thermometers with excited states coupled by electricdipole transitions have lower onset temperatures than those with magnetic-dipole-coupled states due to selection *** insights provide essential guidelines for the optimization of Boltzmann thermometers to operate in an extended temperature range.

关键词： equilibrium excited dynamic

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Fabrication of freestanding Pt nanowires for use as thermal anemometry probes in turbulence measurements

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Microsystems & Nanoengineering 2021年第2期7卷 155-165页

作者： Hai Le-The Christian Küchler Albert van den Berg Eberhard Bodenschatz Detlef Lohse Dominik Krug Physics of Fluids Group MESA+InstituteUniversity of Twente7522 NBEnschedeThe Netherlands BIOS Lab-on-a-Chip Group MESA+InstituteUniversity of Twente7522 NBEnschedeThe Netherlands Max Planck-University of Twente Center for Complex Fluid Dynamics GöttingenGermany Max Planck Institute for Dynamics and Self-Organization 37077GöttingenGermany

We report a robust fabrication method for patterning freestanding Pt nanowires for use as thermal anemometry probes for small-scale turbulence *** e-beam lithography,high aspect ratio Pt nanowires(~300 nm width,~70µm length,~100 nm thickness)were patterned on the surface of oxidized silicon(Si)*** wet etching processes with dry etching processes,these Pt nanowires were successfully released,rendering them freestanding between two silicon dioxide(SiO2)beams supported on Si ***,the unique design of the bridge holding the device allowed gentle release of the device without damaging the Pt *** total fabrication time was minimized by restricting the use of e-beam lithography to the patterning of the Pt nanowires,while standard photolithography was employed for other parts of the *** demonstrate that the fabricated sensors are suitable for turbulence measurements when operated in constant-current mode.A robust calibration between the output voltage and the fluid velocity was established over the velocity range from 0.5 to 5 m s−1 in a SF6 atmosphere at a pressure of 2 bar and a temperature of 21°*** sensing signal from the nanowires showed negligible drift over a period of several ***,we confirmed that the nanowires can withstand high dynamic pressures by testing them in air at room temperature for velocities up to 55 m s−1.

关键词： nanowires turbulence thermal

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Reversible hydrogenation restores defected graphene to graphene

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science China Chemistry 2021年第6期64卷 1047-1056页

作者： Lin Jiang Pauline MGvan Deursen Hadi Arjmandi-Tash Liubov ABelyaeva Haoyuan Qi Jiao He Vincent Kofman Longfei Wu Valery Muravev Ute Kaiser Harold Linnartz Emiel JMHensen Jan PHofmann Grégory FSchneider Leiden Institute of Chemistry Leiden UniversityEinsteinweg 552333CC LeidenThe Netherlands Central Facility for Electron Microscopy Electron Microscopy Group of Materials ScienceUlm UniversityAlbert-Einstein-Allee 11Ulm 89081Germany Laboratory for Astrophysics Leiden ObservatoryLeiden UniversityNiels Bohrweg 22333 CA LeidenThe Netherlands Laboratory for Inorganic Materials and Catalysis Department of Chemical Engineering and ChemistryEindhoven University of TechnologyP.O.Box 5135600 MB EindhovenThe Netherlands Center for Advancing Electronics Dresden(cfaed)and Faculty of Chemistry and Food Chemistry Technical University of Dresden010069 DresdenGermany

Graphene as a two-dimensional material is prone to hydrocarbon contaminations,which can significantly alter its intrinsic electrical ***,we implement a facile hydrogenation-dehydrogenation strategy to remove hydrocarbon contaminations and preserve the excellent transport properties of monolayer *** electron microscopy we quantitatively characterized the improved cleanness of hydrogenated graphene compared to untreated *** situ spectroscopic investigations revealed that the hydrogenation treatment promoted the adsorption of water at the graphene surface,resulting in a protective layer against the re-deposition of hydrocarbon ***,the further dehydrogenation of hydrogenated graphene rendered a more pristine-like basal plane with improved carrier mobility compared to untreated pristine *** findings provide a practical post-growth cleaning protocol for graphene with maintained surface cleanness and lattice integrity to systematically carry a range of surface chemistry in the form of a well-performing and reproducible transistor.

关键词： graphene reversible hydrogenation surface cleanness in situ spectroscopy transistors

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Scale effect of circularly polarized luminescent signal of matter

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National science Review 2023年第5期10卷 232-239页

作者： Siyu Sun Xiaolin Li Chen Xu Yan Li YongZhen Wu Ben L.Feringa He Tian Xiang Ma Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center Frontiers Science Center for Materiobiology and Dynamic ChemistrySchool of Chemistry and Molecular EngineeringEast China University of Science and Technology School of Physics East China University of Science and Technology Stratingh Institute for Chemistry and Zernike Institute for Advanced Materials Faculty of Science and EngineeringUniversity of Groningen

Circularly polarized luminescence(CPL) is an important part in the research of modern luminescent materials and photoelectric ***,chiral molecules or chiral structures are the key factors to induce CPL spontaneous *** this study,a scale-effect model based on scalar theory was proposed to better understand the CPL signal of luminescent *** chiral structures being able to induce CPL,achiral ordered structures can also have a significant influence on CPL *** achiral structures are mainly reflected in the particle scale in micro-order or macro-order,*** CPL signal measured under most conditions depends on the scale of the ordered medium,and does not reflect the inherent chirality of the excited state of the luminescent *** kind of influence is difficult to be eliminated by simple and univers al strategies in *** the same time,it is found that the measurement entropy of CPL detection may be the key factor to determine the isotropy and anisotropy of the CPL *** discovery would bring new opportunities to the research of chiral luminescent *** strategy can also greatly reduce the development difficulty of CPL materials and show high application potential in biomedical,photoelectric information and other fields.

关键词： scale effect circularly polarized luminescent chirality quantum dots perovskite

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Droplet microreactor for high-throughput fluorescence-based measurements of single catalyst particle acidity

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Microsystems & Nanoengineering 2023年第2期9卷 101-111页

作者： Jeroen C.Vollenbroek Anne-Eva Nieuwelink Johan G.Bomer Roald M.Tiggelar Albert van den Berg Bert M.Weckhuysen Mathieu Odijko BIOS Lab on a Chip Group MESA+InstituteUniversity of TwenteHallenweg 157522 NH EnschedeThe Netherlands inorganic Chemistry and Catalysis Debye Institute for Nanomaterials ScienceUtrecht UniversityUniversiteitsweg 993584 CG UtrechtThe Netherlands NanoLab Cleanroom MESA+InstituteUniversity of TwenteHallenweg 157522 NH EnschedeThe Netherlands

The particles of heterogeneous catalysts differ greatly in size,morphology,and most importantly,in *** these catalyst particles in batch typically results in ensemble averages,without any information at the level of individual catalyst *** date,the study of individual catalyst particles has been rewarding but is stll rather slow and often ***,these valuable in-depth studies at the single particle level lack statistical ***,we report the development of a droplet microreactor for high-throughput fluorescence-based measurements of the acidities of individual particles in fluid catalytic cracking(FCC)equilibrium catalysts(ECAT).This method combines systematic screening of single catalyst particles with statistical *** oligomerization reaction of 4-methoxystyrene,catalyzed by the Bronsted acid sites inside the zeolite domains of the ECAT particles,Was performed on-chip at 95 ℃.The fluorescence signal generated by the reaction products inside the ECAT particles was detected near the outlet of the *** high-throughput acidity screening platform was capable of detecting~1000 catalyst particles at a rate of 1 catalyst particle every 2.4 *** number of detected catalyst particles was representative of the overall catalyst particle population with a confidence level of 95%.The measured fluorescence intensities showed a clear acidity distribution among the catalyst particles,with the majority(96.1%)showing acidity levels belonging to old,deactivated catalyst particles and a minority(3.9%)exhibiting high acidity *** latter are potentially of high interest,as they reveal interesting new physicochemical properties indicating why the particles were still highly acidic and reactive.

关键词： catalyst acidity particle

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