Titan g2

Penta-twinned Ag NWs were synthesized by reducing AgNO₃ with ethylene glycol in the presence of polyvinyl pyrrolidone. More details of the NW synthesis process are provided elsewhere45 (link). The solution of Ag NWs was diluted with deionized water and then purified by centrifugation. Single-crystalline Ag NWs were synthesized by physical vapour deposition inside a molecular beam epitaxy system under ultrahigh vacuum condition and substrate temperature of 700 °C. More details of the NW synthesis process are provided elsewhere4 (link).
Conventional TEM observations were performed on JEOL 2010F operated at 200 kV. Atomic-resolution high-angle annular dark-field scanning TEM imaging was performed on a probe-corrected FEI Titan G² 60–300 kV S/TEM equipped with an extreme field emission gun (X-FEG) electron source operated at 200 kV.
Cross-section TEM samples were prepared by embedding Ag NWs into Gatan G1 epoxy with a φ3 Cu tube, cutting the specimen discs with a thickness of ~0.5 mm, mechanically polishing with Allied Multiprep System and finally ion milling the sample via Gatan 791 PIPS while cooling with liquid nitrogen.

The nanobattery setup consists of a SeS₂@CNT working electrode, metallic Na counter/reference electrodes, and Na₂O SE naturally formed on the Na surface. For assembling, SeS₂@CNT was dispersed in ethanol, then dropped to an aluminum rod and dried. The metallic Na was scratched onto another side of the aluminum rod. The assembled nanobatteries were constructed on a microelectrochemical systems (MEMS) heating device, which comprises of an electric circuit and a heating circuit. Subsequently, the device was inserted into a Cs‐corrected environmental TEM (FEI, Titan G2, 300 kV) for observation.
The ASS Na–SeS₂ batteries were assembled in a home‐made mold with a diameter of 10 mm. The as‐prepared composite cathodes with an area loading of 1.34 mg cm⁻², Na₃SbS₄ electrolyte (100 mg), and Na₁₅Sn₄ (50 mg) powders were cold‐pressed under a pressure of 350 MPa for rate and cycling characterizations.

To investigate the structure of the graphene formed at different stages, the Pt foil was quickly pulled out of the high-temperature zone after SACVD growth. The furnace was then shut down and the methane flow was stopped after the furnace temperature had decreased to 600 °C. Finally, the Pt foil was taken out and characterized by SEM (Nova NanoSEM 430, acceleration voltage of 5 kV). The small graphene domains and polycrystalline films were transferred onto Si/SiO₂ (290 nm) substrates using a improved bubbling transfer method11 (link), in which the Poly(methyl methacrylate) (PMMA) used for transfer had a smaller molecular weight (600 kDa, 4 wt.% in ethyl lactate) and the acetone used for removing PMMA was heated at 50 °C to enhance the solubilities, for morphological and quality analysis by optical microscopy (Nikon LV100D) and Raman spectroscopy (JY HR800, 532 nm laser wavelength, 1 μm spot size, 1 s integration time, laser power below 2 mW). The polycrystalline films were transferred to TEM grids by using a improved bubbling transfer method mentioned above for GB analysis by TEM (FEI Tecnai F20, 200 kV; FEI Tecnai T12, 120 kV; FEI Titan G2 equipped with an image-side spherical aberration corrector, 80–300 kV).