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71.
Dr. Shu Min Tan Dr. Carmen C. Mayorga-Martinez Prof. Zdeněk Sofer Prof. Martin Pumera 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(29):6479-6483
Efficient exfoliation and downsizing of Sb2S3 and Bi2S3 layered compounds by using scalable bipolar electrochemistry on their suspensions in aqueous media are here demonstrated. The resulting samples were characterized in detail by transmission electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy; their electrochemistry toward hydrogen evolution was also investigated. Hydrogen evolution ability of exfoliated Sb2S3 and Bi2S3 was investigated and compared to the bulk counterparts. 相似文献
72.
Nithiyanandan Krishnan Devanathan Perumal Siriki Atchimnaidu Kaloor S. Harikrishnan Murali Golla Nilima Manoj Kumar Jemshiya Kalathil Jithu Krishna Dileep K. Vijayan Dr. Reji Varghese 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(5):1037-1041
High aspect ratio, sugar-decorated 2D nanosheets are ideal candidates for the capture and agglutination of bacteria. Herein, the design and synthesis of two carbohydrate-based Janus amphiphiles that spontaneously self-assemble into high aspect ratio 2D sheets are reported. The unique structural features of the sheets include the extremely high aspect ratio and dense display of galactose on the surface. These structural characteristics allow the sheet to act as a supramolecular 2D platform for the capture and agglutination of E. coli through specific multivalent noncovalent interactions, which significantly reduces the mobility of the bacteria and leads to the inhibition of their proliferation. Our results suggest that the design strategy demonstrated here can be applied as a general approach for the crafting of biomolecule-decorated 2D nanosheets, which can perform as 2D platforms for their interaction with specific targets. 相似文献
73.
Junxiong Wu Prof. Francesco Ciucci Prof. Jang-Kyo Kim 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(29):6296-6319
The rapid development of electrochemical energy storage systems requires new electrode materials with high performance. As a two-dimensional material, molybdenum disulfide (MoS2) has attracted increasing interest in energy storage applications due to its layered structure, tunable physical and chemical properties, and high capacity. In this review, the atomic structures and properties of different phases of MoS2 are first introduced. Then, typical synthetic methods for MoS2 and MoS2-based composites are presented. Furthermore, the recent progress in the design of diverse MoS2-based micro/nanostructures for rechargeable batteries, including lithium-ion, lithium-sulfur, sodium-ion, potassium-ion, and multivalent-ion batteries, is overviewed. Additionally, the roles of advanced in situ/operando techniques and theoretical calculations in elucidating fundamental insights into the structural and electrochemical processes taking place in these materials during battery operation are illustrated. Finally, a perspective is given on how the properties of MoS2-based electrode materials are further improved and how they can find widespread application in the next-generation electrochemical energy-storage systems. 相似文献
74.
Yi Liu Jiaqi Wang Shiguo Han Dr. Xitao Liu Maofan Li Zhiyun Xu Wuqian Guo Prof. Maochun Hong Prof. Junhua Luo Prof. Zhihua Sun 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(16):3494-3498
3D perovskite CsPbBr3 has recently taken a blooming position for optoelectronic applications. However, due to the lack of natural anisotropy of optical attributes, it is a great challenge to fulfil polarization-sensitive photodetection. Here, for the first time, we exploited dimensionality reduction of CsPbBr3 to tailor a 2D-multilayered hybrid perovskite, (TRA)2CsPb2Br7 ( 1 , in which TRA is (carboxy)cyclohexylmethylammonium), serving as a potential polarized-light detecting candidate. Its unique quantum-confined 2D structure results in intrinsic anisotropy of electrical conductivity, optical absorbance, and polarization-dependent responses. Particularly, it exhibits remarkable dichroism with the photocurrent ratio (Ipc/Ipa) of ≈2.1, being much higher than that of the isotropic CsPbBr3 crystal and reported CH3NH3PbI3 nanowire (≈1.3), which reveals its great potentials for polarization-sensitive photodetection. Further, crystal-based detectors of 1 show fascinating responses to the polarized light, including high detectivity (>1010 Jones), fast responding time (≈300 μs), and sizeable on/off current ratios (>104). To our best knowledge, this is the first study on 2D Cs-based hybrid perovskite exhibiting strong polarization-sensitivity. The work highlights an effective pathway to explore new polarization sensitive candidates for hybrid perovskites and promotes their future electronic applications. 相似文献
75.
Dr. Isabella A. Vacchi Shi Guo Dr. Jésus Raya Dr. Alberto Bianco Dr. Cécilia Ménard-Moyon 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(29):6591-6598
Graphene oxide (GO) is a versatile platform with unique properties that have found broad applications in the biomedical field. Double functionalization is a key aspect in the design of multifunctional GO with combined imaging, targeting, and therapeutic properties. Compared to noncovalent functionalization, covalent strategies lead to GO conjugates with a higher stability in biological fluids. However, only a few double covalent functionalization approaches have been developed so far. The complexity of GO makes the derivatization of the oxygenated groups difficult to control. The combination of a nucleophilic epoxide ring opening with the derivatization of the hydroxyl groups through esterification or Williamson reaction was investigated. The conditions were selective and mild, thus preserving the structure of GO. Our strategy of double functionalization holds great potential for different applications in which the derivatization of GO with different molecules is needed, especially in the biomedical field. 相似文献
76.
Prof. Dr. Masaki Shimizu Sho Nagano Takumi Kinoshita 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(23):5162-5167
Fluorescence–phosphorescence dual-emissive compounds are valuable tools for ratiometric luminescence sensing. Herein, it is reported that 2,5-bis(phenylsulfonyl)- and 2,5-bis[bis(4-methoxyphenyl)phosphinyl]-1,4-disiloxybenzenes exhibit dual emission with emission peaks that were easily identified without performing time-gated measurement. The disiloxybenzenes in powder simultaneously fluoresced and phosphoresced at 358–374 and 457–470 nm, respectively, under vacuum. The intensity ratios of the phosphorescence/fluorescence maxima of the disiloxybenzenes in powder and in a thin film of poly(methyl methacrylate) were sensitive to temperature and molecular oxygen, respectively. The plots of the relative intensity versus temperature or partial pressure of molecular oxygen were well fitted with calibration curves defined by an exponential approximation with excellent correlation coefficients R2 (0.9708–0.9921), demonstrating the high potential of the disiloxybenzenes as precious metal-free probes applicable to ratiometric luminescence sensing. 相似文献
77.
Thanh-Hai Le Yuree Oh Prof. Hyungwoo Kim Prof. Hyeonseok Yoon 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(29):6360-6401
The fascinating properties of single-layer graphene isolated by mechanical exfoliation have inspired extensive research efforts toward two-dimensional (2D) materials. Layered compounds serve as precursors for atomically thin 2D materials (briefly, 2D nanomaterials) owing to their strong intraplane chemical bonding but weak interplane van der Waals interactions. There are newly emerging 2D materials beyond graphene, and it is becoming increasingly important to develop cost-effective, scalable methods for producing 2D nanomaterials with controlled microstructures and properties. The variety of developed synthetic techniques can be categorized into two classes: bottom-up and top-down approaches. Of top-down approaches, the exfoliation of bulk 2D materials into single or few layers is the most common. This review highlights chemical and physical exfoliation methods that allow for the production of 2D nanomaterials in large quantities. In addition, remarkable examples of utilizing exfoliated 2D nanomaterials in energy and environmental applications are introduced. 相似文献
78.
Ji Wang Nan Li Yuxia Xu Prof. Dr. Huan Pang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(29):6402-6422
Metal–organic framework (MOF) and covalent organic framework (COF) nanosheets are a new type of two-dimensional (2D) materials with unique design principles and various synthesis methods. They are considered ideal electrochemical devices due to the ultrathin thickness, easily tunable molecular structure, large porosity and other unique properties. There are two common methods to synthesize 2D MOF/COF nanosheets: bottom-up and top-down. The top-down strategy mainly includes ultrasonic assisted exfoliation, electrochemical exfoliation and mechanical exfoliation. Another strategy mainly includes interface synthesis, modulation synthesis, surfactant-assisted synthesis. In this Review, the development of ultrathin 2D nanosheets in the field of electrochemistry (supercapacitors, batteries, oxygen reduction, and hydrogen evolution) is introduced, and their unique dimensional advantages are highlighted. 相似文献
79.
Dr. Yuman Sayed-Ahmad-Baraza Dr. Christopher P. Ewels 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(29):6686-6693
Density functional studies of the edges of single-layer 1H-MoS2 are presented. This phase presents a rich variability of edges that can influence the morphology and properties of MoS2 nano-objects, play an important role in industrial chemical processes, and find future applications in energy storage, electronics and spintronics. The so-called Mo-100 %S edges vertical S-dimers were confirmed to be stable, however the authors also identified a family of metastable edges combining Mo atoms linked by two-electron donor symmetrical disulfide ligands and four-electron donor unsymmetrical disulfide ligands. These may be entropically favored, potentially stabilizing them at high temperatures as a “liquid edge” phase. For Mo-50 %S edges, S-bridge structures with 3× periodicity along the edge are the most stable, compatible with a Peierls’ distortion arising from the d-bands of the edge Mo atoms. An additional explanation for this periodicity is proposed through the formation of 3-center bonds. 相似文献
80.
Zudian Dai Mei Wang Yin Zhang Boya Wang Hang Luo Xuemei Zhang Dr. Qian Wang Prof. Yun Zhang Prof. Hao Wu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(40):8784-8793
Lithium–sulfur batteries (LSBs) still suffer from the shuttle effect on the cathode and the lithium dendrite on the anode. Herein, polyacrylonitrile (PAN) is developed into a bifunctional host material to simultaneously address the challenges faced on both the sulfur cathode and lithium anode in LSBs. For the sulfur cathode, PAN is bonded with sulfur to produce sulfurized PAN (SPAN) to avoid the shuttle effect. The SPAN is accommodated into a conductive 3D CNTs-wrapped carbon foam to prepare a self-supporting cathode, which improves the electronic and ionic conductivity, and buffers the volume expansion. Thereby, it delivers reversible capacity, superb rate capability, and outstanding cycling stability. For the Li-metal anode, PAN aerogel is carbonized to give macroporous N-doped cross-linked carbon nanofiber that behaves as a lithiophilic host to regulate Li plating and suppress the growth of Li dendrite. Combining the improvements for both the cathode and anode realizes a remarkable long-term cyclability (765 mAh g−1 after 300 cycles) in a full cell. It provides new opportunity to propel the practical application of advanced LSBs. 相似文献