Microstructure development and twinning in Nb2O5-doped SnO2-CoO ceramics exhibiting promising varistor characteristics

Sara Tominc

Jozef Stefan Institute

Name: Sara Tominc Birth date: April 28th, 1989. Address: Šarhova 101, 2000 Maribor, Slovenia E-mail: sara.tominc@ijs.si Web: https://www.researchgate.net/profile/Sara_TomincEducation:› Diploma (2008–2013): Chemical technology. Faculty of Chemistry and Chemical Engineering, University of Maribor. BSc Thesis: »Immobilization of cholesterol oxidase onto maghemite nanoparticles modified with chitosan« (2013). › Doctorate (2014–): Chemistry. Jožef Stefan International Postgraduate School, Ljubljana. PhD Thesis: »Structural investigations of twin boundaries in natural SnO2 (cassiterite) and SnO2-based ceramics «. Employments:2014/10 – present: Young researcher at Jožef Stefan Institute, Ljubljana. Bibliography:› Articles - 1 scientific paper› Citations – 2 citations› Presentations – 4 talks and 3 posters at conferences, 7 conference contributions. Scientific profile:Sara Tominc started her PhD studies in October 2014. Her basic education is chemical technology with focus on synthesis of nanoparticles. With a growing interest in research work in the field of crystal growth and phase transformations in minerals, she became young researcher at Jožef Stefan Institute. The main tools for her investigations are transmission and scanning electron microscopy techniques, so she is already intensely involved in Slovenian society for microscopy. The main goal of her work is to study the crystal growth mechanism and the twinning of mineral cassiterite from nature and to determine whether the cause of twinning in cassiterite (SnO2) is topotaxial growth on still unknown precursor material, or is the source tropochemical. A new area of research, which she also open in 2015, is the study of twinning in cassiterite (SnO2) in the field of varistors ceramics. Based on microstructural studies of ZnO ceramics, where grain growth was successfully controlled by the formation of inversion boundaries, she made an attempt to apply the same principle to SnO2 ceramics.


We investigated the effects of dual doping of SnO2 varistor ceramics with 1 mol% CoO and different amounts of Nb2O5 (0.1-2 mol%) on the formation of twin boundaries, microstructure development and electrical properties.Already... [ view full abstract ]


  1. Sara Tominc (Jozef Stefan Institute)
  2. Aleksander Rečnik (Jozef Stefan Institute)
  3. Zoran Samardžija (Jozef Stefan Institute)
  4. Goran Drazic (National Institute of Chemistry)
  5. Matejka Podlogar (Jozef Stefan Institute)
  6. Slavko Bernik (Jozef Stefan Institute)
  7. Nina Daneu (Jozef Stefan Institute)

Topic Area

Tunable devices, thermistors, varistors


PS-1C » Poster Session 1 - Symposium C (17:30 - Monday, 9th July, Foyer)

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