Hp 4284a lcr meter

Morphological and elemental characterization of the fabricated composites was performed using scanning electron microscopy (SEM, FEI Quanta Inspect, Thermo Fisher Scientific Inc, Waltham, MA, USA) and energy dispersive X-ray spectroscopy (EDX, 10 keV). The topography and surface roughness of the fabricated samples doped with SiC and ZnO after polishing were analyzed via white light interferometry (WLI) using a 3D optical profilometer (Profil3D^®, Filmetrics, San Diego, CA, USA).
Capacitance measurements were performed using an HP 4284A LCR meter (Hewlett-Packard, Palo Alto, CA, USA). Measurements were performed for frequencies ranging from 1 kHz to 1 MHz and for biases ranging from 0 V to ±2 V. From the capacitance measurements, the dielectric constant was extracted using the following equation: $${\mathrm{C}}_{\mathrm{x}}=\frac{{\mathsf{\epsilon }}_{\mathsf{o}}·{\mathsf{\epsilon }}_{\mathrm{x}}·\mathrm{A}}{\mathrm{d}}$$
where C_x is the measured capacitance, ε_o = 8.854 × 10⁻¹² CV⁻¹ m⁻¹ is the dielectric permittivity of vacuum, ε_x is the composite material dielectric constant, A is the capacitor area, and d is the material thickness.

Fourier transform infrared spectroscopy (FTIR) was conducted using a PerkinElmer (Waltham, MA, USA) frontier infrared spectrometer in the spectral range of 4000–500 cm⁻¹. Proton nuclear magnetic resonances (¹H-NMR) and fluoride nuclear magnetic resonances (¹⁹F-NMR) were obtained using a Bruker (Billerica, MA, USA) (Ascend) 400 MHz instrument in DMSO-d₆ containing tetramethylsilane (TMS) as the internal standard. Scanning electron microscopy (SEM) (JEOL, Tokyo, Japan) was performed with an ULTRA 55 field emission scanning electron microscope (FESEM) in the secondary electron mode with an accelerating voltage of 3 kV. The dielectric and alternating current (AC) conductive properties of the nanocomposites were measured on an HP4284A LCR meter (Hewlett-Packard, Palo Alto, CA, USA) in the frequency range of 100 Hz~1 MHz with 1 V at room temperature. Electric displacement–electric field (D-E) loops were obtained at 10 Hz using a Precision Premier II ferroelectric polarization tester (Radiant, Inc., Renton, WA, USA). Twelve specimens were used for the breakdown strength test for each sample. The energy storage performances were calculated according to the D-E results.

The pH-sensitivity of the CeY_xO_y sensing films was determined by measuring the capacitance–voltage (C–V) curves of their EIS devices against pH buffer solutions (Merck), using a Ag/AgCl reference electrode and a Hewlett–Packard (HP) 4284 A LCR meter (ac signal frequency: 500 Hz); to avoid interference from light and noise, each experiment was performed in the dark at room temperature.