by Hai Lin et al.
New Journal of Physics, 24 (2022)
Excerpt
The synthesis of RNiO2 (R = La, Pr, Nd) samples was conducted in two stages, according to the same procedure as in previous reports. Here, we put an emphasis on bulk PrNiO2, which is obtained for the first time up to our best knowledge.
In the first stage, high-quality PrNiO3 samples were grown under a high-pressure oxygen atmosphere. In the second stage, the precursor PrNiO3 samples were topochemically reduced by applying the following route, mixed with CaH2, sealed in quartz tubes and heated at 270◦C for 40 h.
Afterwards, the mixtures were washed by NH4Cl in ethanol to remove the extra CaH2 and Ca(OH)2. The resulting black powders were PrNiO2. LaNiO2 and NdNiO2 were synthesised in the same way.
The pictures taken by a scanning electron microscope (SEM) indicate that all these samples consist of 1–5μm sized particles, as shown in the insets in figure 1. Last but not least, the samples were stored in sealed centrifuge tubes and handled in the N2 atmosphere in order to avoid degradation caused by water or oxygen in the air.
More about: Topochemical reaction
Low-temperature topochemical reactions which exploit the high mobility of particular components within extended oxide phases, to bring about structure-conserving reactions which form metastable phases.
From: Comprehensive Inorganic Chemistry II (Second Edition), 2013
Style check: Methods sections
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