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1. Edge‐Passivated Monolayer WSe ₂ Nanoribbon Transistors

   https://doi.org/10.1002/adma.202313694  

   Chen, Sihan; Zhang, Yue; King, William_P; Bashir, Rashid; van_der_Zande, Arend_M (July 2024, Advanced Materials)

   Abstract The ongoing reduction in transistor sizes drives advancements in information technology. However, as transistors shrink to the nanometer scale, surface and edge states begin to constrain their performance. 2D semiconductors like transition metal dichalcogenides (TMDs) have dangling‐bond‐free surfaces, hence achieving minimal surface states. Nonetheless, edge state disorder still limits the performance of width‐scaled 2D transistors. This work demonstrates a facile edge passivation method to enhance the electrical properties of monolayer WSe₂nanoribbons, by combining scanning transmission electron microscopy, optical spectroscopy, and field‐effect transistor (FET) transport measurements. Monolayer WSe₂nanoribbons are passivated with amorphous WO_xSe_yat the edges, which is achieved using nanolithography and a controlled remote O₂plasma process. The same nanoribbons, with and without edge passivation are sequentially fabricated and measured. The passivated‐edge nanoribbon FETs exhibit 10 ± 6 times higher field‐effect mobility than the open‐edge nanoribbon FETs, which are characterized with dangling bonds at the edges. WO_xSe_yedge passivation minimizes edge disorder and enhances the material quality of WSe₂nanoribbons. Owing to its simplicity and effectiveness, oxidation‐based edge passivation could become a turnkey manufacturing solution for TMD nanoribbons in beyond‐silicon electronics and optoelectronics. 

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2. LiMo ₈ O ₁₀ : Polar Crystal Structure with Infinite Edge-Sharing Molybdenum Octahedra

   https://doi.org/10.1021/acs.inorgchem.2c01917  

   Messegee, Zachary T.; Gall, Philippe; Bhandari, Hari; Siegfried, Peter E.; Kang, Chang-Jong; Chen, Benjamin; Conti, Carl R.; Chen, Banghao; Croft, Mark; Zhang, Qiang; et al (September 2022, Inorganic Chemistry)

   Polycrystalline LiMo8O10 was prepared in a sealed Mo crucible at 1380 °C for 48 h using the conventional high-temperature solid-state method. The polar tetragonal crystal structure (space group I41md) is confirmed based on the Rietveld refinement of powder neutron diffraction and 7Li/6Li solid-state NMR. The crystal structure features infinite chains of Mo4O5 (i.e., Mo2Mo4/2O6/2O6/3) as a repeat unit containing edge-sharing Mo6 octahedra with strong Mo–Mo metal bonding along the chain. X-ray absorption near-edge spectroscopy of the Mo-L3 edge is consistent with the formal Mo valence/configuration. Magnetic measurements reveal that LiMo8O10 is paramagnetic down to 1.8 K. Temperature-dependent resistivity [ρ(T)] measurement indicates a semiconducting behavior that can be fitted with Mott’s variable range hopping conduction mechanism in the temperature range of 215 and 45 K. The ρ(T) curve exhibits an exponential increase below 5 K with a large ratio of ρ1.8/ρ300 = 435. LiMo8O10 shows a negative field-dependent magnetoresistance between 2 and 25 K. Heat capacity measurement fitted with the modified Debye model yields the Debye temperature of 365 K. 

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3. Nitrogen‐Vacancy Magnetometry of Edge Magnetism in WS ₂ Flakes

   https://doi.org/10.1002/adfm.202512391  

   Fescenko, Ilja; Kumar, Raman; Gas‐Osoth, Thitinun; Wang, Yifei; Lamichhane, Suvechhya; Li, Tianlin; Erickson, Adam; Raghavan, Nina; Delord, Tom; Cress, Cory_D; et al (July 2025, Advanced Functional Materials)

   Abstract Two‐dimentional magnets are of significant interest both as a platform for exploring novel fundamental physics and for their potential in spintronic and optoelectronic devices. Recent bulk magnetometry studies have indicated a weak ferromagnetic response in tungsten disulfide (WS₂), and theoretical predictions suggest edge‐localized magnetization in flakes with partial hydrogenation. Here, room‐temperature wide‐field quantum diamond magnetometry to image pristine and Fe‐implanted WS₂flakes of varying thicknesses (45–160 nm), exfoliated from bulk crystals and transferred to NV‐doped diamond substrates, is used. Direct evidence of edge‐localized stray magnetic fields, which scale linearly with applied external magnetic field (4.4–220 mT), reaching up to ±4.7 µT, is observed. The edge signal shows a limited dependence on the flake thickness, consistent with dipolar field decay and sensing geometry. Magnetic simulations using five alternative models favor the presence of edge magnetization aligned along an axis slightly tilted from the normal to the WS₂flake's plane, consistent with spin canting in antiferromagnetically coupled edge states. Thses findings establish WS₂as a promising platform for edge‐controlled 2D spintronics. 

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4. Nitrogen ion-implanted resistive regions for edge termination of vertical Ga ₂ O ₃ rectifiers

   https://doi.org/10.1116/6.0001347  

   Xia, Xinyi; Xian, Minghan; Fares, Chaker; Sharma, Ribhu; Law, Mark E.; Ren, Fan; Pearton, Stephen J. (December 2021, Journal of Vacuum Science & Technology A)
5. 3-D Edge-Oriented Electrocatalytic NiCo ₂ S ₄ Nanoflakes on Vertical Graphene for Li-S Batteries

   https://doi.org/10.34133/2021/2712391  

   Li, Wenyue; Li, Shiqi; Bernussi, Ayrton A.; Fan, Zhaoyang (March 2021, Energy Material Advances)

   null (Ed.)

   Polysulfide shuttle effect, causing extremely low Coulombic efficiency and cycling stability, is one of the toughest challenges hindering the development of practical lithium sulfur batteries (LSBs). Introducing catalytic nanostructures to stabilize the otherwise soluble polysulfides and promote their conversion to solids has been proved to be an effective strategy in attacking this problem, but the heavy mass of catalysts often results in a low specific energy of the whole electrode. Herein, by designing and synthesizing a free-standing edge-oriented NiCo 2 S 4 /vertical graphene functionalized carbon nanofiber (NCS/EOG/CNF) thin film as a catalytic overlayer incorporated in the sulfur cathode, the polysulfide shuttle effect is largely alleviated, revealed by the enhanced electrochemical performance measurements and the catalytic function demonstration. Different from other reports, the NiCo 2 S 4 nanosheets synthesized here have a 3-D edge-oriented structure with fully exposed edges and easily accessible in-plane surfaces, thus providing a high density of active sites even with a small mass. The EOG/CNF scaffold further renders the high conductivity in the catalytic structure. Combined, this novel structure, with high sulfur loading and high sulfur fraction, leads to high-performance sulfur cathodes toward a practical LSB technology. 

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