A Comparison between Solution-Based Synthesis Methods of ZrO2 Nanomaterials for Energy Storage Applications

Abstract

The present study is focused on the synthesis of zirconium dioxide (ZrO2) nanomaterials using the hydrothermal method assisted by microwave irradiation and solution combustion synthesis. Both synthesis techniques resulted in ZrO2 powders with a mixture of tetragonal and monoclinic phases. For microwave synthesis, a further calcination treatment at 800 °C for 15 min was carried out to produce nanopowders with a dominant monoclinic ZrO2 phase, as attested by X-ray diffraction (XRD) and Raman spectroscopy. The thermal behavior of the ZrO2 nanopowder was investigated by in situ XRD measurements. From the scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images, the presence of near spherical nanoparticles was clear, and TEM confirmed the ZrO2 phases that comprised the calcinated nanopowders, which include a residual tetragonal phase. The optical properties of these ZrO2 nanopowders were assessed through photoluminescence (PL) and PL excitation (PLE) at room temperature (RT), revealing the presence of a broad emission band peaked in the visible spectral region, which suffers a redshift in its peak position, as well as intensity enhancement, after the calcination treatment. The powder resultant from the solution combustion synthesis was composed of plate-like structures with a micrometer size; however, ZrO2 nanoparticles with different shapes were also observed. Thin films were also produced by solution combustion synthesis and deposited on silicon substrates to produce energy storage devices, i.e., ZrO2 capacitors. The capacitors that were prepared from a 0.2 M zirconium nitrate-based precursor solution in 2-methoxyethanol and annealed at 350 °C exhibited an average dielectric constant (κ) of 11 ± 0.5 and low leakage current density of 3.9 ± 1.1 × 10−7 A/cm2 at 1 MV/cm. This study demonstrates the simple and cost-effective aspects of both synthesis routes to produce ZrO2 nanomaterials that can be applied to energy storage devices, such as capacitors.

Scalable Synthesis of ZrO2 Nanoparticles through Imidazolic Precursor and Evaluation of its Energy Storage Performance

“…The peak at 470 cm −1 is attributed to the Zr−O vibration [18] . The confirmation of the successful formation of ZrO 2 nanoparticles was also well‐matched with the previous reported data [19–21] …”

“…[18] The confirmation of the successful formation of ZrO 2 nanoparticles was also well-matched with the previous reported data. [19][20][21]…”

Effect of metal oxide nanoparticles on thermal behavior of polyvinyl alcohol

“…11a, shows that spherical shaped ZrO2 nanoparticles of uniform size (nearly 80 nm) were formed. This is in good agreement with the previously reported work [20,21]. Figure 11b shows that ZrO2 nanoparticles were homogeneously dispersed in the PVA matrix.…”

The absorption properties of ZrO2 nanoparticles in the THz and sub-THz frequency ranges

“…1 shows strong distinct peaks assigned to m-ZrO 2 (ref. 39 and 40 ) 97 cm −1 (A g ), 177 cm −1 (B g ), 189 cm −1 (A g ), 221 cm −1 (B g ), 305 cm −1 (B g ), 331 cm −1 (B g ), 346 cm −1 (A g ), 381 cm −1 (A g ), 474 cm −1 (A g ), 502 cm −1 (B g ), 536 cm −1 (B g ), 557 cm −1 (A g ), 615 cm −1 (B g ), 636 cm −1 (A g ), 753 cm −1 (B g ). There are two small unidentified peaks at 448 cm −1 and 578 cm −1 which are also reported in previous studies.…”