Neoarm

A field emission JSM-IT700HR scanning electron microscope (SEM) with energy-dispersive X-ray spectroscopy (EDS) was used to characterize the morphology and composition of the samples. A Rigaku SmartLab X-ray diffraction (XRD) system was used to investigate the crystalline structure of the sample. The crystalline structure of Pt-NS catalysts was investigated by scanning transmission electron microscopy (STEM) on a probe-corrected JEOL NEOARM operated at an accelerating voltage of 80 kV.

Sample solutions were drop cast on a continuous carbon-coated copper grids with 400 mesh (Ted Pella). The grids were then dried with filter paper and sealed away from moisture before experiments. JEOL NEOARM was operated at 80 kV in low beam conditions. A spot size of 5 and low screen brightness was combined to perform TEM studies with minimum radiation damage from the electron beam. Image J was used to extract plot profiles from the TEM images and make measurements on domain sizes. Ten measurements were performed for each sample.

The morphologies of the Ir_{1 −x}V_xO₂ nanowires were characterized with a scanning electron microscope (SEM, Quanta FEI and Zeiss Auriga 60), and the structure and growth orientations were characterized via TEM (JEOL 3200 TEM), and the chemical composition of the nanowires determined with XEDS in the SEM, JEOL 3200 TEM, and NEOARM atomic resolution analytical electron microscope by JEOL. The Raman spectra were collected at room temperature with a Renishaw inVia confocal Raman microscope system with a 532 nm excitation laser with a nominal laser power of 50 µW and calibrated with a reference Si peak at 520 cm⁻¹.

We performed in situ TEM heating experiments with the HEA samples under under study to intentionally accelerate the surface oxidation of thin TEM foils. The in situ TEM heating experiments were performed using a Gatan heating holder equipped with water connection on a conventional TEM (JEOL JEM-2010 without any correctors) equipment at 500 °C for 20 min. Afterwards, the surface oxidation of the TEM lamellar was examined using HRTEM and STEM modes in an atomic-resolution TEM (JEOL NEO-ARM) to accurately distinguish the SRO-derived diffuse scattering from the oxidation-induced reflections in the EDPs.

The thickness and refractive index of the deposited single oxides of HfO₂ and ZrO₂ and the HZO thin films were evaluated using an ellipsometer (Elli-SE, Ellipso technology, Suwon, Korea). The shape of the thin film cross-section and the elemental composition were analyzed using transmission electron microscopy (TEM) (NEO ARM, JEOL, Tokyo, Japan) and energy-dispersive spectroscopy (EDS) (JED-2300T, JEOL, Tokyo, Japan), respectively. The crystalline structure of the HZO thin films was measured by high-resolution X-ray diffraction (HR-XRD) (Smartlab, Rigaku, Tokyo, Japan) in Bragg–Brentano geometry, and the density of the thin film was calculated through X-ray reflectometry (XRR) analysis on the same instrument. Electrical properties such as the P-E curve and fatigue endurance of the thin film were evaluated using a TF analyzer (TF-2000E, aixACCT, Aachen, Germany) connected to a microprobe station (APX-6B, WIT, Suwon, Korea). Hysteresis loop measurements were performed at a frequency of 1 kHz with a triangle pulse of ±3 V. Fatigue endurance measurements were conducted by the continuous application of a square pulse of ±3 V at 10 kHz along with a 1 kHz triangle pulse that was applied five times at each time point to measure remnant polarization.

TEM was performed with a JEOL NEOARM operating at 200 kV. All images are high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) data. The diameter of the used condenser lens aperture was 40 μm, the probe current was 150 pA, and the camera length was 4 cm. EDS was performed with two detectors provided by JEOL Ltd. and the maps were obtained with DigitalMicrograph, a software developed by Gatan Inc.