# Fileset

[BiFeO3-LiWO3-comment-160524.pdf](https://mdr.nims.go.jp/filesets/4f92973e-d122-48dc-aa6e-5e5e1d9c7c91/download)

## Creator

[Alexei A. Belik](https://orcid.org/0000-0001-9031-2355)

## Rights

[In Copyright](http://rightsstatements.org/vocab/InC/1.0/)

## Other metadata

[Comments on the paper “studies of structural, dielectric, conductivity, leakage current mechanism, and efficiency of complex electroceramic”](https://mdr.nims.go.jp/datasets/96b19a48-f84d-41ec-ad46-345e96c6790f)

## Fulltext

Comments on the paper “Influence of Ba-doping on the structural and physical properties of Sr2−xBaxFeVO6 double perovskites”1  Comments on the paper “Studies of structural, dielectric, conductivity, leakage current mechanism, and efficiency of complex electroceramic”  Alexei A. Belik  Research Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS), Namiki 1-1, Tsukuba, Ibaraki 305-0044, Japan E-mail: Alexei.Belik@nims.go.jp  Abstract The commented paper claims the preparation of a new compound, Bi1/2Li1/2Fe1/2W1/2O3. By this commentary, we showed that erroneous experimental evidence was provided for such claims. We demonstrated that the main phase in the commented paper was Bi2WO6.  Keywords: perovskites; doped BiFeO3; X-ray diffraction; phase analysis; lattice parameters; errors 2  The BiFeO3 perovskite and its derivatives continue to attract a lot of attention of researchers worldwide. S. S. Hota et al. have recently claimed the preparation of a new heavily-doped BiFeO3-related compound with a chemical composition of “Bi1/2Li1/2Fe1/2W1/2O3” (BLFWO) [1]. BLFWO was prepared using a conventional solid-state method from a stoichiometric mixture of Li2CO3, FeCO3, WO3, and Bi2O3 in air at 1053 K for 4 h and at 1023 K for 4 h. An X-ray powder diffraction pattern of BLFWO could be indexed by the authors with lattice parameters of a = 10.0096 Å, b = 9.9673 Å, c = 7.5531 Å, and β = 110.64°. Therefore, the authors of Ref. [1] concluded that a new single-phase compound was prepared, and space group P21 was assigned to BLFWO. However, we found that the majority of observed reflections on the reported X-ray powder diffraction pattern of BLFWO (Figure 1a of this commentary) could be explained by a known phase, Bi2WO6 (Figure 1b). Reflections from Fe2O3 and Li2WO4 could also be seen on the reported X-ray powder diffraction pattern of BLFWO; other weak reflections could not be identified. Therefore, a situation with BLFWO resembles a situation with another similar compound, “Bi1/2K1/2Fe1/2W1/2O3”, claimed by the same authors [2]. It was shown that “Bi1/2K1/2Fe1/2W1/2O3” does not exist, and a mixture of Bi2WO6, K2WO4, and Fe2O3 was investigated instead [3].  Therefore, a mixture of (partly) known phases was investigated in Ref. [1] instead of a new compound, “Bi1/2Li1/2Fe1/2W1/2O3”. The authors of Ref. [1] did not perform any standard phase-analysis procedures, assumed that a single-phase compound was obtained, and moved to indexing attempts resulting in erroneous claims.  References [1] S. S. Hota, D. Panda, R. N. P. Choudhary, Studies of structural, dielectric, conductivity, leakage current mechanism, and efficiency of complex electroceramic. Ceram. Int. 50 (2024) 4031–4045. [2] S. S. Hota, D. Panda, R. N. P. Choudhary, Fabrication and physical characteristics of K/W double doped BiFeO3 complex electro-ceramic; (Bi1/2K1/2)(Fe1/2W1/2)O3. J. Alloys Compd. 976 (2024) 172900. doi: 10.1016/j.jallcom.2023.172900 [3] A. A. Belik, Comments on the paper “Fabrication and physical characteristics of K/W double doped BiFeO3 complex electro-ceramic; (Bi1/2K1/2)(Fe1/2W1/2)O3”. J. Alloys Compd. 977 (2024) 173434. doi: 10.1016/j.jallcom.2024.173434  3    Figure 1. (a) An experimental X-ray powder diffraction pattern of a “Bi1/2Li1/2Fe1/2W1/2O3” sample from Figure 1a of Ref. [1]. (b) Calculated X-ray diffraction patterns of Bi2WO6 (the black curve and the black tick marks for possible Bragg reflection positions; International Center for Diffraction Data (ICDD) Powder Diffraction File (PDF) record 73-2020), Fe2O3 (the green curve and the green tick marks; PDF 33-0664), and Li2WO4 (the blue curve and the blue tick marks; PDF 79-2006). The calculated patterns (intensity ratios) correspond to a 1:1 molar mixture of Bi2WO6 and Fe2O3 [3]. Figure 1a is reproduced with the permission from Elsevier.   Abstract