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Sensing nanoscale electromagnetic forces when the heat is on

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National Science Review 2024年第7期11卷 64-65页

作者： Eric O.Potma department of chemistry University of California

In scanning probe microscopy(SPM),a sharp tip scans across a sample to produce an image with nanometer-scale resolution or better. SPM contrast is derived from the physical interplay between the tip and the sample. A special class of SPM techniques measures forces when the tip–sample junction is illuminated by an external light source. Photo-induced forces can be sensitive to the optical properties of the sample, thus enabling nanoscale imaging with spectroscopic,material-specific contrast.

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Silvery fullerene in Ag102 nanosaucer

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National Science Review 2024年第7期11卷 158-167页

作者： Zhi Wang Yuchen Wang Chengkai Zhang Yan-Jie Zhu Ke-Peng Song Christine M.Aikens Chen-Ho Tung Di Sun School of chemistry and Chemical Engineering Shandong University department of chemistry Kansas State University

Despite the discovery of a series of fullerenes and a handful of noncarbon clusters with the typical topology of Ih-C60, the smallest fullerene with a large degree of curvature, C20, and its other-element counterparts are difficult to isolate experimentally. In coinage metal nanoclusters（NCs）, the first all-gold fullerene, Au32, was discovered after a long-lasting pursuit, but the isolation of similar silvery fullerene structures is still challenging. Herein, we report a flying saucer-shaped 102-nuclei silver NC（Ag102） with a silvery fullerene kernel of Ag32, which is embraced by a robust cyclic anionic passivation layer of（KPO4）10. This Ag32kernel can be viewed as a non-centered icosahedron Ag12encaged into a dodecahedron Ag20, forming the silvery fullerene of Ag12@Ag20. The anionic layer（KPO4）10is located at the interlayer between the Ag32kernel and Ag70shell, passivating the Ag32silvery fullerene and templating the Ag70shell. The ~tBuPhS-and CF3COO-ligands on the silver shell show a regioselective arrangement with the 60 ~tBuPhS-ligands as expanders covering the upper and lower of the flying saucer and 10 CF3COO-as terminators neatly encircling the edges of the structure. In addition, Ag102 shows excellent photothermal conversion efficiency（η） from the visible to near-infrared region（η = 67.1% ± 0.9% at 450 nm, 60.9% ± 0.9% at 660 nm and 50.2% ± 0.5% at 808 nm）, rendering it a promising material for photothermal converters and potential application in remote laser ignition. This work not only captures silver kernels with the topology of the smallest fullerene C20, but also provides a pathway for incorporating alkali metal（M） into coinage metal NCs via M-oxoanions.

关键词： silvery fullerene >Ag102 nanosaucer cyclic anionic passivation layer photothermal conversion DFT calculation

Charting the course to solid-state dual-ion batteries

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Carbon Energy 2024年第3期6卷 132-177页

作者： Habtom D.Asfaw Antonia Kotronia Nuria Garcia-Araez Kristina Edström Daniel Brandell department of chemistry Ångström LaboratoryUppsala UniversityUppsalaSweden department of chemistry University of SouthamptonSouthamptonUK

An electrolyte destined for use in a dual-ion battery(DIB)must be stable at the inherently high potential required for anion intercalation in the graphite electrode,while also protecting the Al current collector from anodic dissolution.A higher salt concentration is needed in the electrolyte,in comparison to typical battery electrolytes,to maximize energy density,while ensuring acceptable ionic conductivity and operational *** recent years,studies have demonstrated that highly concentrated organic electrolytes,ionic liquids,gel polymer electrolytes(GPEs),ionogels,and water-in-salt electrolytes can potentially be used in *** can help reduce the use of solvents and thus lead to a substantial change in the Coulombic efficiency,energy density,and long-term cycle life of ***,GPEs are suited to manufacture compact DIB designs without separators by virtue of their mechanical strength and electrical *** this review,we highlight the latest advances in the application of different electrolytes in DIBs,with particular emphasis on GPEs.

关键词： anion intercalation concentrated electrolytes dual-ion battery graphite ionic liquids polymer electrolyte

Multicolor circularly polarized phosphorescence of axially chiral binuclear platinum(Ⅱ) complexes

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Science China chemistry 2024年第11期67卷 3757-3766页

作者： Jintong Song Rui Zeng Hui Xiao Hailiang Ni Zong-Xiang Xu Haifeng Xiang College of chemistry and Materials Science Sichuan Normal University department of chemistry Southern University of Science and Technology College of chemistry Sichuan University

D-A charge transfer, including through-bond charge transfer and through-space charge transfer between two different electron donors（D） and electron acceptors（A）, is a fundamental and powerful tool to tune the optical properties of organic dyes. Herein,we demonstrate a unique strategy to tune phosphorescence and circularly polarized luminescence properties of axially chiral binuclear Pt（Ⅱ） complexes through long-range charge transfer, even though these molecules have two totally identical segments on either side of the chiral core. The presence of axial chirality would break not only the symmetry of molecular structure and π-conjugation system but also the symmetry of charge distribution for long-range charge transfer. These binaphthyl-based Pt（Ⅱ）complexes bearing coordinated atoms far away from chiral axis exhibit no Pt-Pt interactions but colorful concentrationdependent phosphorescence with quantum yield up to 86.4% and could be applied as emitters in highly efficient solutionprocessed organic light-emitting diodes to achieve luminance, luminance efficiency, power efficiency, external quantum efficiency, and asymmetry factor up to 8.94 × 10～3cd m-2, 41.9 cd A-1, 18.8 lm W-1, 12.6% and 2.98 × 10-3, respectively. Therefore,the present work affords a new and simple way to utilize the inherently asymmetric advantage of chirality for the design of D-Abased organic dyes.

关键词： Pt(II) complexes organic light-emitting diodes circularly polarized phosphorescence axial chirality

Increasing polymer scission rate by tying an overhand knot

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Science China chemistry 2024年第11期67卷 3498-3499页

作者： Yuheng Hu Jennifer T.Ou Jim Y.Huang Yuanning Feng department of chemistry and Biochemistry The University of Oklahoma

Similar to the phenomenon of knotted ropes in life, knotted climbing ropes will reduce their strength due to knots. Although computer simulations [1], theoretical speculation[2,3], and intuition [3] suggest that similar processes may occur at the nanoscale, this hypothesis has not been experimentally proven before. With the increasing maturity of molecular recognition and self-assembly, a research communication by Leigh et al. [4] published in Nature chemistry introduced a molecular overhand knot into a polymer to study its effect on the scission rate of the polymer chain under tension.

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Terminal-selective C（sp3）–H borylation of unbranched alkanes enabled by intermolecular radical sampling and LMCT photocatalysis

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National Science Review 2024年第5期11卷 96-98页

作者： Zhexuan Lei Jie Wu department of chemistry National University of Singapore

The selective functionalization of C（sp3）–H bonds with subtle differences in alkanes is highly sought after due to its atom-and step-efficiency. The activation of C（sp3）–H bonds through hydrogen atom transfer （HAT） has been extensively exploited to produce a valueadded product from unfunctionalized material [1,2].

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Photochromic radical states in 3D covalent organic frameworks with zyg topology for enhanced photocatalysis

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National Science Review 2024年第7期11卷 177-188页

作者： Tian-Tian Ma Guo-Zhang Huang Xiao-Han Wang Yan Liang Run-Han Li Bin Wang Su-Juan Yao Jia-Peng Liao Shun-Li Li Yong Yan Ya-Qian Lan School of chemistry South China Normal University department of chemistry Guangdong Provincial Key Laboratory of Catalytic Chemistry Southern University of Science and Technology

Covalent-organic frameworks（COFs） with photoinduced donor-acceptor（D-A） radical pairs show enhanced photocatalytic activity in principle. However, achieving long-lived charge separation in COFs proves challenging due to the rapid charge recombination. Here, we develop a novel strategy by combining[6 + 4] nodes to construct zyg-type 3D COFs, first reported in COF chemistry. This structure type exhibits a fused Olympic-rings-like shape, which provides a platform for stabilizing the photoinduced D-A radical pairs. The zyg-type COFs containing catalytically active moieties such as triphenylamine and phenothiazine（PTZ） show superior photocatalytic production rates of hydrogen peroxide（H2O2）. Significantly, the photochromic radical states of these COFs show up to 400% enhancement in photocatalytic activity compared to the parent states, achieving a remarkable H2O2synthesis rate of 3324 μmol g-1h-1, which makes the PTZ-COF one of the best crystalline porous photocatalysts in H2O2production. This work will shed light on the synthesis of efficient 3D COF photocatalysts built on topologies that can facilitate photogenerating D-A radical pairs for enhanced photocatalysis.

关键词： 3D covalent-organic frameworks photochromic radical states donor and acceptor hydrogen peroxide photocatalysis

Coordination-driven self-assembly of a molecular 818knot and molecular borromean rings

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Science China chemistry 2024年第11期67卷 3652-3656页

作者： Xiang Gao Dong Liu Hai-Ning Zhang Guo-Xin Jin department of chemistry Fudan University

We report the facile construction of a molecular 818knot and a molecular Borromean rings assembly through self-assembly directed by Cp*Rh corner units. Two curved ligands of similar size and shape were used in this study. The slight steric differences between the two ligands induce the formation of distinctly different topologies of the assembled products. The structures were confirmed by single-crystal X-ray analysis and nuclear magnetic resonance spectroscopy.

关键词： coordination-driven Cp*Rh 818 knot Borromean rings

Inorganic ionic polymerization:From biomineralization to materials manufacturing

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Nano Research 2024年第2期17卷 550-569页

作者： Yanhua Sang Kexin Qin Ruikang Tang Zhaoming Liu department of chemistry Zhejiang UniversityHangzhou 310058China

Biomineralization process regulates the growth of inorganic minerals by complex molecules,proteins,and cells,endowing bio-materials with marvels structures and excellent *** intricate structures and compositions found in biominerals have inspired scientists to design and synthesize numerous artificial biomimetic *** methodology for controlling the formation of inorganics plays a pivotal role in achieving biomimetic structures and ***,the current approach predominantly relies on the classical nucleation theory,which hinders the precise preparation of inorganic materials by replicating the biomineralization ***,the development of“inorganic ionic polymerization”strategy has enabled us to regulate the arrangement of inorganic ions from solution to solid phase,which establishes an artificial way to produce inorganic materials analogous to the biomineralization *** on inorganic ionic polymerization,a series of achievements have been realized for the biomimetic preparation,including moldable construction of inorganic materials,hard tissue regeneration,and high-performance biomimetic ***,the utilization of inorganic ionic polymerization has also facilitated the production of numerous advanced materials,including novel structures that exceed the current knowledge of materials *** inorganic ionic polymerization system provides new artificial strategies and methodologies for the controllable synthesis of inorganics,which mimics the biomineralization process,paving the way for the future development of more high-performance materials.

关键词： biomineralization inorganic ionic polymerization biomimetic materials crystal growth synthetic methodology