31 results on '"Yutao Sang"'
Search Results
2. Ultrasound‐Directed Symmetry Breaking and Spin Filtering of Supramolecular Assemblies from only Achiral Building Blocks
- Author
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Yutao Sang, Qirong Zhu, Xiaoqin Zhou, Yuqian Jiang, Li Zhang, and Minghua Liu
- Subjects
General Medicine ,General Chemistry ,Catalysis - Abstract
Here we describe the self-assembly of an achiral molecule into macroscopic helicity as well as the emergent chirality selective spin filtering effect. It was found that benzene-1,3,5-tricarboxamide (BTA) motif with an aminopyridine group in each arm could coordinate with Ag(I) and self-assemble into nanospheres. Upon sonication symmetry breaking occurred and the nanospheres transfer into helical nanofibers with strong CD signals. Although the sign of the CD signals appeared randomly, it could be controlled by using the as-made chiral assemblies as a seed. Furthermore, it was found that the charge transport of the helical nanofibers was highly selective with a spin-polarization transport of up to 45% although the chiral nanofibers are composed exclusively from achiral building blocks. The work demonstrated a new example of the symmetry breaking under sonication and the chirality selective spin filtering effect.
- Published
- 2023
3. The Effect of Anesthesia Gases on the Oxygen Reduction Reaction
- Author
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Anu Gupta, Yutao Sang, Claudio Fontanesi, Luca Turin, and Ron Naaman
- Abstract
The oxygen reduction reaction (ORR) is of high importance, among others because of its role in cellular respiration and in the operation of fuel cells. Recently, a possible relation between respiration and general anesthesia has been found. This work aims to explore whether anesthesia related gases affect the ORR. In ORR, oxygen which is in its triplet ground state is reduced to form products that are all in the singlet state. While this process is “in principle” forbidden because of spin conservation, it is known that if the electrons transferred in the ORR are spin polarized, the reaction occurs efficiently. Here we show, in electrochemical experiments, that the efficiency of the oxygen reduction is reduced by the presence of general anesthetics in solution. We suggest that a spin-orbit coupling to the anesthetics depolarizes the spins. This causes both a reduction in reaction efficiency and a change in the reaction products. The findings may point to a possible relation between ORR efficiency and anesthetic action.TOC
- Published
- 2022
4. Chirality enhances oxygen reduction
- Author
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Yutao Sang, Francesco Tassinari, Kakali Santra, Wenyan Zhang, Claudio Fontanesi, Brian P. Bloom, David H. Waldeck, Jonas Fransson, and Ron Naaman
- Subjects
Multidisciplinary ,Other Physics Topics ,chirality ,Annan fysik ,Electrons ,fuel cells ,spin ,Catalysis ,Electron Transport ,Oxygen ,respiration ,Electrodes ,Oxidation-Reduction ,oxygen - Abstract
Controlled reduction of oxygen is important for developing clean energy technologies, such as fuel cells, and is vital to the existence of aerobic organisms. The process starts with oxygen in a triplet ground state and ends with products that are all in singlet states. Hence, spin constraints in the oxygen reduction must be considered. Here, we show that the electron transfer efficiency from chiral electrodes to oxygen (oxygen reduction reaction) is enhanced over that from achiral electrodes. We demonstrate lower overpotentials and higher current densities for chiral catalysts versus achiral ones. This finding holds even for electrodes composed of heavy metals with large spin–orbit coupling. The effect results from the spin selectivity conferred on the electron current by the chiral assemblies, the chiral-induced spin selectivity effect.
- Published
- 2022
5. Simultaneous High-Purity Enantiomeric Resolution of Conglomerates Using Magnetic Substrates
- Author
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Eyal Capua, Debkumar Bhowmick, Maximilian Halbauer, Yutao Sang, Kakali Santra, Francesco Tassinari, Ron Naaman, and Yossi Paltiel
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Materials science ,010405 organic chemistry ,Resolution (electron density) ,General Chemistry ,010402 general chemistry ,Condensed Matter Physics ,01 natural sciences ,Molecular physics ,0104 chemical sciences ,Perpendicular ,Molecule ,General Materials Science ,Enantiomer ,Spin-½ - Abstract
Applying magnetic substrates, magnetized perpendicular to the surface, we were able to crystallize from racemic solution pure conglomerates of several molecules. The resolution is based on the spin...
- Published
- 2021
6. Steering Nanohelix and Upconverted Circularly Polarized Luminescence by Using Completely Achiral Components
- Author
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Junchen Guo, Minghua Liu, Xue Jin, Yutao Sang, Sanxu Chen, Minghao Zhou, and Pengfei Duan
- Subjects
chemistry.chemical_classification ,Materials science ,General Engineering ,Supramolecular chemistry ,General Physics and Astronomy ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Acceptor ,Photon upconversion ,0104 chemical sciences ,chemistry ,Chemical physics ,Molecule ,Non-covalent interactions ,General Materials Science ,Self-assembly ,0210 nano-technology ,Luminescence ,Chirality (chemistry) - Abstract
Enormous attention has been paid to upconverted circularly polarized luminescence (UC-CPL). However, so far, chiral species are still needed in UC-CPL materials, either through the covalent or noncovalent bond. Here, we report a general supramolecular coassembly approach for the fabrication of UC-CPL systems from completely achiral components. We have found that an achiral C3-symmetric molecule could form a chiral nanohelix through symmetry breaking, which could serve as a general helical platform to endow achiral guests with induced chirality and CPL activity. Two different photon upconversion systems, namely, triplet-triplet annihilation photon upconversion (TTA-UC) donor/acceptor pairs and inorganic lanthanide upconversion nanoparticles (UCNPs), are selected. When these two systems coassembled with the chiral nanohelix made from an achiral C3-symmetric molecule, hybrid nanohelix structures formed and UC-CPL activity was induced. Through such an approach, we demonstrated that the fabrication of the UC-CPL materials does not require any chiral molecules. Moreover, we have shown that the polarization of UC-CPL can be tuned by the helicity of the nanohelix, which could be controlled through the seeded vortex. Our work provides a general approach for designing tunable UC-CPL materials from completely achiral motifs, which largely expands the research scope of the CPL materials.
- Published
- 2021
7. Homologous and Heterologous Chiral Supramolecular Polymerization from Exclusively Achiral Building Blocks
- Author
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Chengxi Li, Yutao Sang, Xue Jin, Pengfei Duan, and Minghua Liu
- Subjects
Polymers ,General Chemistry ,General Medicine ,Catalysis ,Polymerization - Abstract
Among the enticing issues of chiral origins are: how chirality is born from the initial achiral units and the mechanisms for the transfer of chiral information. In this work, by combining a physical vortex and chiral seeds, a general process is revealed to generate chiral supramolecular polymers from achiral C
- Published
- 2022
8. Mechanically Controlled and Consecutively Boosted Circularly Polarized Luminescence of Nanoassemblies from Achiral Molecules
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Minghua Liu, Zhaocun Shen, Yutao Sang, Dong Yang, and Pengfei Duan
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Materials science ,Supramolecular chemistry ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Supramolecular assembly ,Crystallography ,General Energy ,Molecule ,Physical and Theoretical Chemistry ,0210 nano-technology ,Luminescence - Abstract
Consecutive boosted circularly polarized luminescence (CPL) with controlled handedness has been demonstrated in a supramolecular assembly from a completely achiral molecule. It is found that achira...
- Published
- 2020
9. The role of electrons’ spin in DNA oxidative damage recognition
- Author
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Qirong Zhu, Yael Kapon, Aaron M. Fleming, Suryakant Mishra, Kakali Santra, Francesco Tassinari, Sidney R. Cohen, Tapan Kumar Das, Yutao Sang, Deb K. Bhowmick, Cynthia J. Burrows, Yossi Paltiel, and Ron Naaman
- Subjects
General Energy ,General Engineering ,General Physics and Astronomy ,General Materials Science ,General Chemistry - Published
- 2022
10. Chirality enhances oxygen reduction
- Author
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Jonas Fransson, David H. Waldeck, Wenyan Zhang, Francesco Tassinari, Ron Naaman, Yutao Sang, and Kakali Santra
- Subjects
Chemical physics ,Chemistry ,Chirality (chemistry) ,Oxygen reduction - Abstract
Controlled reduction of oxygen is important for developing clean energy technologies, such as fuel cells, and is vital to the existence of aerobic organisms. The process starts with oxygen in a triplet ground state and ends with products that are all in singlet states. Hence, spin constraints in the oxygen reduction must be considered. Here we show that electron transfer from chiral electrodes to oxygen (oxygen reduction reaction) is enhanced over that from achiral electrodes. We demonstrate lower overpotentials and higher current densities for chiral catalysts versus achiral ones. This finding holds even for electrodes composed of heavy metals with large spin orbit coupling. The effect results from the spin selectivity conferred on the electron current by the chiral assemblies, the chiral induced spin selectivity effect.
- Published
- 2021
11. Steering Triplet-Triplet Annihilation Upconversion through Enantioselective Self-Assembly in a Supramolecular Gel
- Author
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Dong Yang, Pengfei Duan, Tonghan Zhao, Minghua Liu, Yutao Sang, and Jianlei Han
- Subjects
Chemistry ,High Energy Physics::Lattice ,Enantioselective synthesis ,Supramolecular chemistry ,General Chemistry ,Photochemistry ,Biochemistry ,Acceptor ,Catalysis ,Photon upconversion ,Colloid and Surface Chemistry ,Self-assembly ,Enantiomer ,Homochirality ,Luminescence - Abstract
Research on chiral selection and recognition not only is of fundamental importance in resolving the origin of biological homochirality, but also is instructive in the fabrication of controlled molecular organization in supramolecular systems to modulate their chirality-related functional properties. Here we report an enantioselective assembly process between a chiral energy donor and two enantiomeric energy acceptors, which further results in chirality-controlled energy transfer and enantioselective triplet-triplet annihilation upconversion (TTA-UC). It is found that the chiral energy donor Pd(II) octaethylporphyrin derivative PdOEP-LG12 (RD) can selectively coassemble with the chiral energy acceptor LGAn (RA) with the same chiral scaffold but tends to form segregation with the energy acceptor DGAn (SA) with the opposite chiral scaffold in a thermodynamic equilibrium state. Thus, the coassembly of RA/RD shows more effective triplet-triplet energy transfer (TTET) and stronger upconverted luminescence and upconverted circularly polarized luminescence in comparison to the segregation of SA/RD. The establishment of such an enantioselective TTA-UC system highlights the applications of chirality-regulated triplet fusion in optoelectronic materials.
- Published
- 2021
12. Boosting the circularly polarized luminescence of small organic molecules via multi-dimensional morphology control
- Author
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Pengfei Duan, Yutao Sang, Kai Ma, Jin Zhou, Tifeng Jiao, Minghua Liu, Wenjie Chen, Dong Yang, and Xue Jin
- Subjects
Materials science ,Nanostructure ,010405 organic chemistry ,Supramolecular chemistry ,General Chemistry ,010402 general chemistry ,Excimer ,01 natural sciences ,Small molecule ,0104 chemical sciences ,Nanomaterials ,Morphology control ,Chemical engineering ,Molecule ,Luminescence - Abstract
Achieving a higher dissymmetry factor is a crucial issue in developing circularly polarized luminescence (CPL) materials. Here, by tailoring the solvent composition and the morphology of the same chiral emissive small molecules (R- or S-SPAn), circularly polarized emission with a boosted dissymmetry factor (two orders) was realized. It was found that by regulating the water fraction in the mixed THF/H2O, we were able to achieve kinetic control over association of chiral emissive R- or S-SPAn into various nanostructures with 0D nanospheres, 2D nanoflakes and 3D stacked nanoflakes. These nanostructures are all CPL active. Remarkably, the dissymmetry factors of the nanostructures were significantly enhanced compared to those of the molecules and further boosted in different morphologies, from ∼10−4 (0D nanospheres) to 10−3 (2D flake) to ∼10−2 (3D nanoflakes). The enlarged glum value could be assigned to a good packing induced strong luminescence of an excimer. This strategy provides an efficient way to fabricate higher dissymmetry factor CPL organic nanomaterials by only changing the supramolecular architectures while using the same chiral small molecules.
- Published
- 2019
13. The chiral amine triggered self-assembly of achiral emissive molecules into circularly polarized luminescent supramolecular assemblies
- Author
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Dong Yang, Yutao Sang, Minghua Liu, and Pengfei Duan
- Subjects
010405 organic chemistry ,Chemistry ,Metals and Alloys ,Supramolecular chemistry ,General Chemistry ,010402 general chemistry ,Photochemistry ,01 natural sciences ,Catalysis ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,chemistry.chemical_compound ,Monomer ,Materials Chemistry ,Ceramics and Composites ,Molecule ,Self-assembly ,Enantiomer ,Luminescence ,Chiral amine - Abstract
Enantiomeric diaminocyclohexane was found to trigger the self-assembly of achiral monomers into chiral supramolecular assemblies with strong circularly polarized luminescence.
- Published
- 2019
14. Nanoarchitectonics through supramolecular gelation: formation and switching of diverse nanostructures
- Author
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Minghua Liu and Yutao Sang
- Subjects
Nanostructure ,Materials science ,Chemistry (miscellaneous) ,Process Chemistry and Technology ,Materials Chemistry ,Biomedical Engineering ,Supramolecular chemistry ,Nanoarchitectonics ,Energy Engineering and Power Technology ,Chemical Engineering (miscellaneous) ,Nanotechnology ,Soft materials ,Industrial and Manufacturing Engineering - Abstract
Supramolecular gels are currently an important class of soft materials that are attracting great interest. The gelation process has been proven to be a powerful approach for the construction of diverse and uniform architectures. Generally, these architectures are on the nanoscale and hierarchically self-assembled from small molecules. Nanoarchitectonics tries to bridge the gap between molecules and nanostructures, while supramolecular gelation provides a good platform to realize such a goal. While the design of the gelator molecules and the function of the gel are important topics, here, we focus on how small molecules can be fabricated into nanostructures through gelation, which is in fact the connection between the microstructures to the macroscopic functions. We showed meritorious examples of typical architectures constructed through the supramolecular gelation process. Then some examples showing the transformation or switching between different nanostructures are presented, which reflected the unique responsiveness of the gel system. Through these two key parts, we hope to provide useful insights into the design and control of functional nanoarchitectures via supramolecular gelation.
- Published
- 2019
15. Nanotrumpets and circularly polarized luminescent nanotwists hierarchically self-assembled from an achiralC3-symmetric ester
- Author
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Pengfei Duan, Minghua Liu, and Yutao Sang
- Subjects
Supramolecular chirality ,Nanostructure ,Materials science ,010405 organic chemistry ,Metals and Alloys ,General Chemistry ,010402 general chemistry ,01 natural sciences ,Catalysis ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Self assembled ,Crystallography ,Materials Chemistry ,Ceramics and Composites ,Molecule ,Luminescence - Abstract
An achiralC3-symmetric molecule was found to self-assemble into various hierarchical nanostructures such as nanotwists, nanotrumpets and nanobelts, in which the twisted fibers showed supramolecular chirality as well as circularly polarized luminescence although the compound is achiral.
- Published
- 2018
16. Supramolecular gelatons: towards the design of molecular gels
- Author
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Minghua Liu, Yutao Sang, Dian Niu, and Guanghui Ouyang
- Subjects
inorganic chemicals ,Chemistry ,Organic Chemistry ,technology, industry, and agriculture ,Supramolecular chemistry ,Nanotechnology ,macromolecular substances ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Covalent bond ,biological sciences ,Molecule ,lipids (amino acids, peptides, and proteins) ,0210 nano-technology ,Structural unit - Abstract
The fabrication and application of supramolecular gels have achieved great progress in the past few decades. Although several reviews and books have well summarized the design, properties and functions of certain supramolecular gels, a comprehensive overview is still lacking to reveal the design strategy of the supramolecular gels. In this review, we propose a concept of a supramolecular gelaton, which is a structural unit or molecule for the design and construction of the supramolecular gels, to show how to design the targeted functional gels. We classify the gelaton into two types. One is a covalent gelaton that when covalently connects with other functional groups results in a molecule that can become a gelator. The other type is a non-covalent gelaton, which is a gelator molecule that can assist other gelator or non-gelator molecules to form gels. We hope that the concept of supramolecular gelatons will provide useful guidance and understanding of the design of gelator molecules and preparation of supramolecular gels.
- Published
- 2018
17. Assembly of colloidal cuprous oxide nanocrystals and study of its magnetic and electrocatalytic properties
- Author
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Binghui Xu, Rongyue Wang, Yutao Sang, Xiu Song Zhao, Hongliang Li, Jing Xue, and Peizhi Guo
- Subjects
Aqueous solution ,Materials science ,Inorganic chemistry ,Oxide ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Electrocatalyst ,01 natural sciences ,0104 chemical sciences ,Micrometre ,Magnetization ,chemistry.chemical_compound ,Colloid ,Colloid and Surface Chemistry ,Nanocrystal ,chemistry ,Self-assembly ,0210 nano-technology - Abstract
Colloidal nanocrystal assemblies (CNAs) of cuprous oxide (Cu2O) are controllably synthesized by in-situ self-assembling primary Cu2O nanocrystals, in which Cu2O CNAs assemblied by nanocrystals of 8–10 nm were about 0.6 μm and Cu2O CNAs assemblied by nanocrystals of 32 nm were about 1.8 μm. From room temperature magnetization measurement results, both of the CNAs showed ferromagnetic behavior with very small saturation magnetization (Ms) values and 10 nm nanocrystal-based CNAs had the largest Ms value of about 9.2 emu/g. Electrochemical experimental results showed that submicron Cu2O CNAs were able to detect dopamine and uric acid quickly while micrometer Cu2O CNAs were not. Cu2O CNAs formed by 8 nm nanocrystals showed the highest electrocatalytic activity in oxygen reduction reaction and displayed the best adsorptive ability to remove Congo red in aqueous solutions, which can be recylced after a simple heat treatment. Furthermore, the formation mechanism and the relationship between crystalline size and assembly of primary nanocrystals as well as physicochemical properties of Cu2O CNAs have been discussed and analyzed.
- Published
- 2017
18. Structural Regulation of PdCu2 Nanoparticles and Their Electrocatalytic Performance for Ethanol Oxidation
- Author
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Jing Xue, Yutao Sang, Hongliang Li, Xiu Song Zhao, Wanneng Ye, Peizhi Guo, and Guangting Han
- Subjects
Materials science ,Ethanol ,Morphology (linguistics) ,Inorganic chemistry ,Nanoparticle ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Electrochemistry ,01 natural sciences ,0104 chemical sciences ,Catalysis ,chemistry.chemical_compound ,X-ray photoelectron spectroscopy ,Chemical engineering ,chemistry ,Transmission electron microscopy ,General Materials Science ,0210 nano-technology ,Current density - Abstract
Two types of PdCu2 nanoparticles were prepared through one-pot synthesis and a two-step reducing process, named as PdCu2-1 and PdCu2-2, respectively. The morphology and structure of as-prepared samples were investigated by transmission electron microscopy, high-resolution transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and inductively coupled plasma-optical emission spectrometry. Results showed that more Pd atoms were buried in the inside of PdCu2-1, whereas more available Pd sites were distributed on the surface of PdCu2-2. The electrochemical measurements indicated that both PdCu2-1 and PdCu2-2 nanoparticles showed a higher electrocatalytic activity than that for pure Pd nanoparticles. In particular, PdCu2-2 predictably exhibited a better stability and durability as well as a lower onset potential and a higher catalytic current density than that of PdCu2-1 toward ethanol oxidation in alkaline media. On the basis of these studies, the formation mechanisms of both th...
- Published
- 2016
19. Capacitive behavior of chestnut shell-based porous carbon electrode in ionic liquid electrolytes
- Author
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Xiu Song Zhao, Yuqian Cui, Changna Wen, Peizhi Guo, Lulu Cheng, and Yutao Sang
- Subjects
Supercapacitor ,Tetrafluoroborate ,Nanotechnology ,02 engineering and technology ,Electrolyte ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Electrochemistry ,01 natural sciences ,Capacitance ,0104 chemical sciences ,chemistry.chemical_compound ,Colloid and Surface Chemistry ,chemistry ,Chemical engineering ,Electrode ,Ionic liquid ,Molecule ,0210 nano-technology - Abstract
This paper studies the electrochemical behaviors of symmetric supercapacitors with the porous carbon obtained from chestnut shells as active materials and ionic liquids as electrolytes, including 1-ethyl-3-methylimidazolium bis[(trifluoromethyl) sulfonyl]imide (EMImTF 2 N), 1-ethyl-3-methylimidazolium tetrafluoroborate (EMImBF 4 ) and 1-Butyl-3-methylimidazolium tetrafluoroborate (BMImBF 4 ). Experimental data observed at a current density of 0.1 A/g showed that symmetric supercapacitor using EMImBF 4 as the electrolyte had the maximum specific capacitance of 208.7 F/g, while 180.8 F/g for EMImTF 2 N and 134.6 F/g for BMImBF 4 . However, specific capacitance of supercapacitors assembled with EMImBF 4 , EMImTF 2 N and BMImBF 4 respectively retained 62.9%, 94.5% and 71.5% of the initial values after 2000 galvanostatic charge-discharge cycles. The relationship between the molecular structure of ionic liquids and electrochemical properties of the supercapacitors was discussed based on the experimental data.
- Published
- 2016
20. Circularly polarized luminescence of achiral open-shell π-radicals
- Author
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Wenjie Chen, Qingxian Jin, Yutao Sang, Sanxu Chen, Jianlei Han, Xuefeng Yang, Shengzhi Dong, Feng Li, Pengfei Duan, and Haoqing Guo
- Subjects
Materials science ,010405 organic chemistry ,Radical ,Metals and Alloys ,Supramolecular chemistry ,Physics::Optics ,General Chemistry ,010402 general chemistry ,Photochemistry ,01 natural sciences ,Catalysis ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Magnetic field ,Liquid crystal ,Physics::Atomic and Molecular Clusters ,Materials Chemistry ,Ceramics and Composites ,Molecular materials ,Chirality (chemistry) ,Luminescence ,Open shell - Abstract
Stable luminescent π-radicals with doublet emission have attracted growing attention for functional molecular materials. However, their chiroptical properties, particularly their doublet emission-based circularly polarized luminescence, have never been investigated. Here, we investigate the circularly polarized luminescence (CPL) properties of a series of achiral luminescent open-shell π-radicals through various chirality regulation approaches, including induction by a magnetic field, supramolecular coassembly and chiral liquid crystal encapsulation.
- Published
- 2019
21. Boosting the circularly polarized luminescence of small organic molecules
- Author
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Kai, Ma, Wenjie, Chen, Tifeng, Jiao, Xue, Jin, Yutao, Sang, Dong, Yang, Jin, Zhou, Minghua, Liu, and Pengfei, Duan
- Subjects
Chemistry - Abstract
By regulating the composition of solvents, the assembled nanostructures of chiral molecules transformed from 0D nanospheres to 3D nanoflakes, which showed significantly amplified circularly polarized luminescence., Achieving a higher dissymmetry factor is a crucial issue in developing circularly polarized luminescence (CPL) materials. Here, by tailoring the solvent composition and the morphology of the same chiral emissive small molecules (R- or S-SPAn), circularly polarized emission with a boosted dissymmetry factor (two orders) was realized. It was found that by regulating the water fraction in the mixed THF/H2O, we were able to achieve kinetic control over association of chiral emissive R- or S-SPAn into various nanostructures with 0D nanospheres, 2D nanoflakes and 3D stacked nanoflakes. These nanostructures are all CPL active. Remarkably, the dissymmetry factors of the nanostructures were significantly enhanced compared to those of the molecules and further boosted in different morphologies, from ∼10–4 (0D nanospheres) to 10–3 (2D flake) to ∼10–2 (3D nanoflakes). The enlarged glum value could be assigned to a good packing induced strong luminescence of an excimer. This strategy provides an efficient way to fabricate higher dissymmetry factor CPL organic nanomaterials by only changing the supramolecular architectures while using the same chiral small molecules.
- Published
- 2019
22. Optically Active Upconverting Nanoparticles with Induced Circularly Polarized Luminescence and Enantioselectively Triggered Photopolymerization
- Author
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Pengfei Duan, Minghua Liu, Yuangang Li, Xue Jin, Xuefeng Zhu, Yutao Sang, and Yonghong Shi
- Subjects
Materials science ,Diacetylene ,General Engineering ,Enantioselective synthesis ,General Physics and Astronomy ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,medicine.disease_cause ,Photochemistry ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,Wavelength ,Photopolymer ,Polymerization ,chemistry ,medicine ,General Materials Science ,Self-assembly ,0210 nano-technology ,Luminescence ,Ultraviolet - Abstract
In this work, lanthanide-doped upconversion nanoparticles (UCNPs) showing upconverted circularly polarized luminescence were demonstrated in an organic–inorganic co-assembled system. Achiral UCNPs (NaYF4:Yb/Er or NaYF4:Yb/Tm) can be encapsulated into chiral helical nanotubes through the procedure of co-gelation. These co-gel systems display intense upconverted circularly polarized luminescence (UC-CPL) ranging from ultraviolet (UV, 300 nm) to near-infrared (NIR, 850 nm) wavelength. In addition, the UV part of UC-CPL can be used to initiate the enantioselective polymerization of diacetylene.
- Published
- 2019
23. Circularly Polarized Luminescence in Nanoassemblies: Generation, Amplification, and Application
- Author
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Pengfei Duan, Minghua Liu, Tonghan Zhao, Yutao Sang, and Jianlei Han
- Subjects
3D optical data storage ,Materials science ,Mechanical Engineering ,Supramolecular chemistry ,Nanotechnology ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Nanomaterials ,Key factors ,Mechanics of Materials ,General Materials Science ,Self-assembly ,0210 nano-technology ,Chirality (chemistry) ,Luminescence ,Inorganic nanoparticles - Abstract
Currently, the development of circularly polarized luminescent (CPL) materials has drawn extensive attention due to the numerous potential applications in optical data storage, displays, backlights in 3D displays, and so on. While the fabrication of CPL-active materials generally requires chiral luminescent molecules, the introduction of the "self-assembly" concept offers a new perspective in obtaining the CPL-active materials. Following this approach, various self-assembled materials, including organic-, inorganic-, and hybrid systems can be endowed with CPL properties. Benefiting from the advantages of self-assembly, not only chiral molecules, but also achiral species, as well as inorganic nanoparticles have potential to be self-assembled into chiral nanoassemblies showing CPL activity. In addition, the dissymmetry factor, an important parameter of CPL materials, can be enhanced through various pathways of self-assembly. Here, the present status and progress of self-assembled nanomaterials with CPL activity are reviewed. An overview of the key factors in regulating chiral emission materials at the supramolecular level will largely boost their application in multidisciplinary fields.
- Published
- 2019
24. Cooperative Chirality and Sequential Energy Transfer in a Supramolecular Light-Harvesting Nanotube
- Author
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Yutao Sang, Guanghui Ouyang, Pengfei Duan, Minghua Liu, Lukang Ji, Yuqian Jiang, and Dong Yang
- Subjects
Quantitative Biology::Biomolecules ,Physics::Biological Physics ,Supramolecular chirality ,Work (thermodynamics) ,Nanotube ,Materials science ,010405 organic chemistry ,High Energy Physics::Lattice ,Supramolecular chemistry ,General Chemistry ,General Medicine ,010402 general chemistry ,Acceptor ,01 natural sciences ,Catalysis ,0104 chemical sciences ,Condensed Matter::Materials Science ,Chemical physics ,Chirality (chemistry) ,Luminescence ,Excitation - Abstract
By constructing a supramolecular light-harvesting chiral nanotube in the aqueous phase, we demonstrate a cooperative energy and chirality transfer. It was found that a cyanostilbene-appended glutamate compound (CG) self-assembled into helical nanotubes exhibiting both supramolecular chirality and circularly polarized luminescence (CPL). When two achiral acceptors, ThT and AO, with different energy bands were co-assembled with the nanotube, the CG nanotube could transfer its chirality to both of the acceptors. The excitation energy could be transferred to ThT but only be sequentially transferred to AO. During this process, the CPL ascribed to the acceptor could be sequentially amplified. This work provides a new insight into the understanding the cooperative chirality and energy transfer in a chiral supramolecular system, which is similar to the natural light-harvesting antennas.
- Published
- 2018
25. Experimental and theoretical studies on the effect of functional groups on carbon nanotubes to its oxygen reduction reaction activity
- Author
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Xiu Song Zhao, Jintao Zhang, Zichao Li, Hao Li, Peizhi Guo, Hongliang Li, Aiping Fu, and Yutao Sang
- Subjects
Chemical substance ,Chemistry ,02 engineering and technology ,Electrolyte ,Carbon nanotube ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Catalysis ,law.invention ,Colloid and Surface Chemistry ,Deprotonation ,Chemical engineering ,Magazine ,law ,Surface modification ,Organic chemistry ,0210 nano-technology ,Science, technology and society - Abstract
Functionalization of carbon nanotubes (CNTs) has been proven to be an effective method to modulate their properties including electrocatalytic activity. Here, we report the catalytic properties of CNTs modified with various functional groups in the oxygen reduction reaction (ORR). Experimental data show that ORR activity of CNTs is enhanced markedly with increasing content of carboxyl groups, and MWNT-COOH sample display the highest current density and most positive onset potential among the studied catalysts. Remarkably, the functionalized CNTs exhibit excellent long-time stability and tolerance towards alcohols. Both experimental and theoretical results suggest that the deprotonated state of carboxyl groups promote the ORR electrocatalytic performance of CNTs in an alkaline electrolyte.
- Published
- 2016
26. Electrochemical reaction of nitrobenzene and its derivatives on glassy carbon electrode modified with MnFe2O4 colloid nanocrystal assemblies
- Author
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Xiu Song Zhao, Yutao Sang, Hongliang Li, Yuqian Cui, Peizhi Guo, Zhen Li, and Wanneng Ye
- Subjects
Inorganic chemistry ,Metals and Alloys ,02 engineering and technology ,Glassy carbon ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Electrocatalyst ,Electrochemistry ,01 natural sciences ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Nitrobenzene ,Nitrosobenzene ,chemistry.chemical_compound ,Colloid ,chemistry ,Nanocrystal ,Materials Chemistry ,Electrical and Electronic Engineering ,Phenylhydroxylamine ,0210 nano-technology ,Instrumentation - Abstract
The electrochemical reduction behavior of nitrobenzene was studied on glassy carbon electrodes modified with MnFe 2 O 4 colloid nanocrystal assemblies. The crystalline size and structure of the colloid nanocrystal assemblies were found to play important roles in determining the catalytic activity of the electrode towards nitrobenzene. It was found that nitrobenzene was first reduced to phenylhydroxylamine via a four-electron reduction pathway, then phenylhydroxylamine was oxidized to nitrosobenzene by losing two-electron on the electrode. The electrochemical reaction mechanisms of p -nitrotoluene and m -dinitrobenzen on the electrodes were discussed and analyzed based on the experimental data.
- Published
- 2016
27. Synthesis of Palladium Colloidal Nanoparticle Aggregates and Their Electrocatalysis of Ethanol in Alkaline Media
- Author
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Wanneng Ye, Zichao Li, Qinchao Wang, Yutao Sang, Jing Xue, Hongliang Li, Xiu Song Zhao, Peizhi Guo, and Guangting Han
- Subjects
Materials science ,Inorganic chemistry ,Nanoparticle ,chemistry.chemical_element ,02 engineering and technology ,Electrolyte ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Electrocatalyst ,Electrochemistry ,01 natural sciences ,0104 chemical sciences ,Catalysis ,Colloid ,stomatognathic system ,chemistry ,Transmission electron microscopy ,General Materials Science ,0210 nano-technology ,Palladium - Abstract
Palladium nanoparticle aggregates (Pd-NPAs) with various sizes were prepared by regulating the stability of Pd colloids. Structures of Pd-NPAs and their performances for electrooxidation of ethanol were investigated using power X-ray diffraction, transmission electron microscopy and electrochemical measurements. Experimental data illustrated that the size of Pd-NPAs, the concentration of electrolyte and the process of electrocatalysis jointly affected their electrocatalytic properties. The on-set potentials were negative-shifted during the electrocatalysis of ethanol as the concentration of KOH in the electrolytes continuously increased, while the catalytic current density reached the highest value in 2 M KOH electrolyte. The change of on-set potential, peak potential and peak current of Pd-NPAs during the electrooxidation of ethanol were systematically investigated and analyzed. A "size-electrolyte-process" mechanism was proposed to explain the variation of the electrocatalytic activity promoting in alkane media.
- Published
- 2016
28. Nanotrumpets and circularly polarized luminescent nanotwists hierarchically self-assembled from an achiral C
- Author
-
Yutao, Sang, Pengfei, Duan, and Minghua, Liu
- Abstract
An achiral C3-symmetric molecule was found to self-assemble into various hierarchical nanostructures such as nanotwists, nanotrumpets and nanobelts, in which the twisted fibers showed supramolecular chirality as well as circularly polarized luminescence although the compound is achiral.
- Published
- 2018
29. Self-Assembly and Directed Assembly
- Author
-
Minghua Liu, Hejin Jiang, Yutao Sang, and Li Zhang
- Subjects
Nanostructure ,Materials science ,Nanoparticle ,Nanotechnology ,Self-assembly - Published
- 2018
30. Structural Regulation of PdCu
- Author
-
Jing, Xue, Guangting, Han, Wanneng, Ye, Yutao, Sang, Hongliang, Li, Peizhi, Guo, and X S, Zhao
- Abstract
Two types of PdCu
- Published
- 2016
31. Insights into the electrocatalysis of nitrobenzene using chemically-modified carbon nanotube electrodes
- Author
-
Peizhi Guo, George Zhao, Qinchao Wang, Yutao Sang, and Baoyan Wang
- Subjects
Nanotube ,Multidisciplinary ,Materials science ,Carbon nanotube ,Electrochemistry ,Electrocatalyst ,Ascorbic acid ,Article ,law.invention ,Nitrobenzene ,chemistry.chemical_compound ,Modified carbon ,Chemical engineering ,chemistry ,law ,Electrode - Abstract
The electrochemical behavior of nitrobenzene and its derivatives at chemically-functionalized multi-wall carbon nanotubes (MWNTs) modified electrodes was studied. Experimental results showed that hydroxyl-containing MWNTs exhibited the highest electrocatalytic activity among the used MWNTs because of its weak capacitive features and oxygen-containing functional groups. The cycle voltammetrys of nitrobenzene derivatives on the MWNTs modified electrodes can be easily tuned by changing the substituted groups of nitrobenzene. Based on the experimental data, the electrochemical reaction mechanisms of nitrobenzene and its derivatives on the MWNTs modified electrodes have been discussed and analyzed.
- Published
- 2014
Catalog
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