Amorphous, Monoclinic, and Tetragonal Porous Zirconia Through a Controlled Self-Sustained Combustion Route

Abstract

Porous, large surface area, metastable zirconias, are of importance to catalytic, electrochemical, biological, and thermal insulation applications. Combustion synthesis is a very commonly used method for producing such zirconias. However, its rapid nature makes control difficult. A simple modification has been made to traditional solution combustion synthesis to address this problem. It involves the addition of starch to yield a starting mixture with a “dough‐like” consistency. Just 5 wt% starch is seen to significantly alter the combustion characteristics of the “dough.” In particular, it helps to achieve better control over reaction zone temperature that is significantly lower than the one calculated by the adiabatic approximation typically used in self‐propagating high‐temperature synthesis. The effect of such control is demonstrated by the ability to tune dough composition to yield zirconias with different phase compositions from the relatively elusive “amorphous” to monoclinic (>30 nm grain size) and tetragonal pure zirconia (<30 nm grain size). The nature of this amorphous phase has been investigated using infrared spectroscopy. Starch content also helps tailor porosity in the final product. Zirconias with an average pore size of about 50 μm and specific surface area as large as 110 m2/g have been obtained.

Interaction between Amorphous Zirconia Nanoparticles and Graphite: Electrochemical Applications for Gallic Acid Sensing Using Carbon Paste Electrodes in Wine

“…However, when they are presented as discrete particles, on analysis by the Zetasizer, the sizes range averagely from 20 nm to about 470 nm. [42]. These micro-particle-like sizes of some of the ZrO 2 are consistent with the XRD results, which shows that the compounds are in amorphous form.…”

Chemically enhanced thermal stability of anodized nanostructured zirconia membranes

“…Based on previous experience we attribute the exothermic peak indicated in the DTA traces to crystallization. 39 In case of the nanoporous structure, there is little difference in devitrification between the treated (472 C) and non-treated membranes (492 C). Thus, ammonia solution treatment does not seem to have a significant effect on the onset of devitrification of the nanoporous membrane.…”

Sintesis Bahan Monoklinik Zirkonia Berukuran Nano dari Prekursor Zirkonium Klorida Menggunakan Templat Polietilen Glikol

“…Kwon et al (2017) menambahkan bahwa produk sinter m-ZrO 2 nano memiliki konduktivitas listrik 1,1 × 10 -4 S/cm. Sedangkan Ahmad et al 2017 Sejumlah metode sintesis bahan ZrO 2 berukuran nano telah banyak dikembangkan, antara lain proses hidrotermal (Chen et al 2005;Zhu et al 2007;Arantes et al 2010, Esmaeilifar et al 2014, sistem mikroemulsi (Liu et al 2002), combustion synthesis (Raghavendra et al 2011), proses solvothermal (Kil et al 2012), metode sol-gel (Trunec et al 2013;Bumajdad et al 2018), metode templat (Septawendar et al 2011;Septawendar et al 2013), the green biogenic synthesis (Shanthi & Tharani 2016), dan metode aging ultrasonik . Metode tersebut umumnya digunakan didalam proses sintesis bahan ZrO 2 nano dengan fasa tetragonal.…”