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In Situ Atomic Tracking on the Interfacial Etching and Reconfiguration of Cu-ReSe 2 Contact during Thermal Annealing
The Schottky barrier height can be greatly affected by the metal diffusion, reaction, and covalent bonding formation at the contact. Exploring novel methods and revealing the fundamental mechanisms for contact engineering are of vital importance for microelectronic devices. Here, in this study, the annealing induced interfacial reactions at Cu-ReSe 2 contact are dynamically revealed from the atomic scale. Accompanied by the diffusion of Se to Cu, ReSe 2 is gradually decomposed to a thin Re interlayer through a “chain-by-chain” manner. Theoretical calculations show that the Cu atoms can facilitate the chemical bond breaking of ReSe 2 , significantly lowering the Se diffusion energy barrier toward Cu. The formed Re/ReSe 2 heterostructure presents a metal-like band structure, which underscores the critical role of Cu in altering the interfacial chemistry and promoting carrier transport across the interface. Our results can provide vital insights into the contact properties of ReSe 2 and provide a possible method for fabricating high-performance ReSe 2 -based devices.
Coupling into Hyperbolic Carbon-Nanotube Films with a Deep-Etched Antenna Grating
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Revitalizing interface in protonic ceramic cells by acid etch
Protonic ceramic electrochemical cells hold the promise to be operated at intermediate temperatures below 600 °C. Although the high proton conductivity of the bulk electrolyte has been demonstrated, it cannot be fully utilized in electrochemical full cells due to unknown causes. A practical solution is thus urgently needed. Here we showed that it comes from poor contacts between the low-temperature processed oxygen electrode-electrolyte interface. We demonstrated that a simple acid treatment can effectively rejuvenate the high-temperature annealed electrolyte surface, resulting in reactive bonding between the oxygen electrode and the electrolyte and improved electrochemical performance and stability. This enables exceptional protonic ceramic fuel-cell performance down to 350 °C, with peak power densities of 1.6 W cm -2 at 600 °C, 650 mW cm -2 at 450 °C, and 300 mW cm -2 at 350 °C, as well as stable electrolysis operations at large current densities above 3.9 A cm -2 under 1.4 V applied voltage at 600 °C. Furthermore, our work highlights the critical role of interfacial engineering in ceramic electrochemical devices and offers new understanding and practices towards sustainable energy infrastructure.
Etching of transition metal dichalcogenide monolayers into nanoribbon arrays
Two-dimensional transition metal dichalcogenide (TMDC) nanoribbons are reported to exhibit interesting properties distinctly different from their 2D analogues, including a change of transport properties depending on the edge structure, enhanced exciton correlation effect and thermoelectric property. In this work we report a successful preparation method for large arrays of 2D TMDC nanoribbons without a template, using a reducing agent aqueous etchant. This approach is a simple and tuneable way for generating TMDC ( e.g. MoS 2 and MoSe 2 ) nanoribbons from CVD grown 2D TMDCs on Si/SiO 2 through liquid phase mechano-chemical reaction. The reducing agent converts Mo(IV) from the defect sites to a lower oxidation state, thus expanding the defects. Water acts as a detaching and tearing medium that pulls the TMDC flake into nanoribbons. The area of conversion, density, and aspect ratio of the nanoribbons can be tuned by concentration and potency of the etchant. The 2D nanoribbons possess high structural integrity, zigzag edges with chalcogen termination, and an increase of bandgap when ribbon width decreases. This method allows a scalable approach for 2D nanoribbons to be prepared for various applications.
Sub-micron thick liquid sheets produced by isotropically etched glass nozzles
Liquid sheet jet formation holds immense promise to provide a continuously replenished target for static structural biology and high energy density studies conducted in X-ray free electron laser, synchrotron, and pulsed electron facilities.
High electron mobility recovery in AlGaN/GaN 2DEG channels regrown on etched surfaces
Not Available
Energy-dependent etching-related impacts on CR-39 alpha detection efficiency for the Rn-222 and Rn-220 decay chains
Not provided.
Simulation of nonlinear superconducting rf losses derived from characteristic topography of etched and electropolished niobium surfaces
Not Available