Synthesis and physical properties of perovskite Sm$_{1-x}$Sr$_x$NiO$_3$ (x = 0, 0.2) and infinite-layer Sm$_{0.8}$Sr$_{0.2}$NiO$_2$ nickelates

Chengping He; Xue Ming; Qing Li; Xiyu Zhu; Jin Si; Hai-Hu Wen

doi:10.1088/1361-648X/abfb90

paper

Synthesis and physical properties of perovskite Sm $_{1 - x}$ Sr $_{x}$ NiO $_{3}$ (x = 0, 0.2) and infinite-layer Sm $_{0.8}$ Sr $_{0.2}$ NiO $_{2}$ nickelates

arXiv:2010.11777 · doi:10.1088/1361-648X/abfb90

Abstract

Recently, superconductivity at about 9-15K was discovered in Nd $_{1 - x}$ Sr $_{x}$ NiO $_{2}$ infinite-layer thin films, which has stimulated enormous interests in related rare-earth nickelates. Usually, the first step to synthesize this 112 phase is to fabricate the RNiO $_{3}$ phase, however, it was reported that the 113 phase is very difficult to be synthesized successfully due to the formation of unusual Ni $^{3 +}$ oxidation state. And the difficulty of preparation is enhanced as the ionic radius of rare-earth element decreases. In this work, we report the synthesis and investigation on multiple physical properties of polycrystalline perovskites Sm $_{1 - x}$ Sr $_{x}$ NiO $_{3}$ (x = 0, 0.2) in which the ionic radius of Sm $^{3 +}$ is smaller than that of Pr $^{3 +}$ and Nd $^{3 +}$ in related superconducting thin films. The structural and compositional analyses conducted by X-ray diffraction and energy dispersive X-ray spectrum reveal that the samples mainly contain the perovskite phase of Sm $_{1 - x}$ Sr $_{x}$ NiO $_{3}$ with small amount of NiO impurities. Magnetization and resistivity measurements indicate that the parent phase SmNiO $_{3}$ undergoes a paramagnetic-antiferromagnetic transition at about 224K on a global insulating background. In contrast, the Sr-doped sample Sm $_{0.8}$ Sr $_{0.2}$ NiO $_{3}$ shows a metallic behavior from 300K down to about 12K, while below 12K the resistivity exhibits a slight logarithmic increase. Meanwhile, from the magnetization curves, we can see that a possible spin-glass state occurs below 12K in Sm $_{0.8}$ Sr $_{0.2}$ NiO $_{3}$ . Using a soft chemical reduction method, we also obtain the infinite-layer phase Sm $_{0.8}$ Sr $_{0.2}$ NiO $_{2}$ with square NiO $_{2}$ planes. The compound shows an insulating behavior which can be described by the three-dimensional variable-range-hopping model. And superconductivity is still absent in the polycrystalline Sm $_{0.8}$ Sr $_{0.2}$ NiO $_{2}$ .

arXiv comment13 pages, 6 figures

Synthesis and physical properties of perovskite Sm $_{1 - x}$ Sr $_{x}$ NiO $_{3}$ (x = 0, 0.2) and infinite-layer Sm $_{0.8}$ Sr $_{0.2}$ NiO $_{2}$ nickelates

Abstract

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Synthesis and physical properties of perovskite Sm1−x​Srx​NiO3​ (x = 0, 0.2) and infinite-layer Sm0.8​Sr0.2​NiO2​ nickelates

Abstract

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Cited by in corpus (16)

Synthesis and physical properties of perovskite Sm $_{1 - x}$ Sr $_{x}$ NiO $_{3}$ (x = 0, 0.2) and infinite-layer Sm $_{0.8}$ Sr $_{0.2}$ NiO $_{2}$ nickelates