ORIGINAL PAPER Occurrence of Ferromagnetic Behavior in ZrO 2 by Ni Substitution Beyond x = 0.01 Shreenu Pattanaik 1 & Dilip Kumar Mishra 1 & Satyabadi Martha 2 & Geetikamayee Padhy 3 & Siddhartha Kumar Pradhan 3 & Ramasamy Sakthivel 3 & Sachindra Nath Sarangi 4 Received: 17 September 2019 /Accepted: 23 October 2019 # Springer Science+Business Media, LLC, part of Springer Nature 2019 Abstract A series of Zr 1-x Ni x O 2 nanocrystalline powders were synthesized by chemical route and then calcined at 750 °C for 5 h. A mixed phase of monoclinic and tetragonal phase of ZrO 2 has been observed in XRD patterns and Raman studies. The tetragonal phase of ZrO 2 increases up to a Ni concentration of x = 0.025 and thereafter suppression of the tetragonal phase is observed with the increase in monoclinic phase of ZrO 2 . At lower concentration of Ni of x = 0.01, the material manifests with diamagnetic property and then a diamagnetic to ferromagnetic transition is established at above than x = 0.01. The saturation magnetization increases with increase in Ni concentration up to x = 0.025 and then decreases for Ni concentration of x = 0.03 in Ni substituted ZrO 2 . The sudden fall in saturation magnetization in Zr 0.97 Ni 0.03 O 2 arises due to the superexchange interactions between two neighboring Ni 2+ ions which lead to antiferromagnetism in the material and suppress the ferromagnetic ordering. Keywords ZrO 2 . Mixed phase . Diamagnetism . Antiferromagnetism . Superexchange interaction 1 Introduction In the neoteric era, miscellaneous researches have been ac- complished in order to know the spin transport mechanism and ferromagnetic ordering in oxide-based diluted magnetic semiconductors (ODMS) [1, 2], which is a fundamental source for data storage, spin transport, and spintronics device applications [3–5]. Since from last few decades, the diluted magnetic semiconductor oxides is a topic of concern due to its charge and spin phenomena, which associates with both semi- conducting and magnetic properties, respectively. According to the previous research analysis, the III–V semiconductors have ferromagnetic property with low Curie temperature, i.e., far below room temperature, whereas the II–VI semicon- ductors exhibit room temperature ferromagnetism above Curie temperature. So for device application, the ferromagnet- ic property should recline in the room temperature range [6–13]. Transition metal-doped wide band gap diluted mag- netic semiconductors like ZnO, TiO 2 , SnO 2 , HfO 2 , and ZrO 2 have shown the room temperature ferromagnetic property above Curie temperature due to the strong exchange interac- tion between the localized “d” electrons of the transition metals and the conduction electrons [14–23]. The room tem- perature ferromagnetism is also noticed in oxide-based un- doped semiconductors, which may originate due to the intro- duction of various intrinsic defects states such as vacancies, interstitials, and clusters [22, 23]. Instead of other metal oxides, we have chosen ZrO 2 for our study due to some interesting peculiar properties such as p-type wide band gap semiconducting property, poly- morphic phases, and mechanical, thermal, optical, and electrical properties. It is the material of interest in various fields like constructional ceramics, bio-ceramics, catalyst, oxygen sensor, solid-state electrolytes, solid oxide fuel cells, thermal barrier coatings, and electro-optical materials [24–28]. The martensitic phase transitions are materialized, with the advancement of temperature and a phase * Dilip Kumar Mishra dilipiuac@gmail.com; dilipmishra@soa.ac.in 1 Department of Physics, Faculty of Engineering and Technology (ITER), Siksha ‘O’ Anusandhan Deemed to be University, Bhubaneswar, Odisha 751 030, India 2 Government (SSD) +2 Science College, Badabharandi, Umerkote, Odisha 764073, India 3 CSIR-Institute of Minerals and Materials Technology (CSIR), Bhubaneswar, Odisha 751013, India 4 Institute of Physics, P.O. Sainik School, Sachivalaya Marg, Bhubaneswar, Orissa 751004, India Journal of Superconductivity and Novel Magnetism https://doi.org/10.1007/s10948-019-05346-8