• A comprehensive study on improved power materials for high-temperature thermoelectric generators 

      Bittner, Michael; Kanas, Nikola; Hinterding, Richard; Steinbach, Frank; Räthel, Jan; Schrade, Mattias; Wiik, Kjell; Einarsrud, Mari-Ann; Feldhoff, Armin (Journal article; Peer reviewed, 2019)
      Dense Ca3Co4O9-NaxCoO2-Bi2Ca2Co2O9 (CCO-NCO-BCCO) nanocomposites were produced from sol-gel derived Ca2.25Na0.3Bi0.35Tb0.1Co4O9 powder by four methods: Hot-pressing (HP), spark plasma sintering (SPS) and pressureless ...
    • All oxide thermoelectric device based on Ca0.931Mn0.98Ta0.02O3-δ-Ca3Co4O9 pn-junction 

      Kolobekken, Sara Hizon (Master thesis, 2017)
      Metal oxides are promising thermoelectric (TE) material candidates for TE modules operational in a range of 300-1200 K in air. In this work a TE oxide module was fabricated by co-sintering the p-type material Ca3Co4O9 ...
    • All-oxide thermoelectric module with in situ formed non-rectifying complex p-p-n junction and transverse thermoelectric effect 

      Kanas, Nikola; Bittner, Michael; Desissa, Temesgen Debelo; Singh, Sathya Prakash; Norby, Truls Eivind; Feldhoff, Armin; Grande, Tor; Wiik, Kjell; Einarsrud, Mari-Ann (Journal article; Peer reviewed, 2018)
      All-oxide thermoelectric modules for energy harvesting are attractive due to high temperature stability, low cost, and the potential to use non-scarce and non-toxic elements. Thermoelectric modules are mostly fabricated ...
    • Chemical stability of Ca3Co4−xO9+δ/CaMnO3−δ p–n junction for oxide-based thermoelectric generators 

      Gunnæs, Anette Eleonora; Tofan, Raluca; Berland, Kristian; Gorantla, Sandeep Madhukar; Storaas, Thomas Aarflot; Desissa, Temesgen Debelo; Schrade, Matthias; Persson, Clas; Einarsrud, Mari-Ann; Wiik, Kjell; Norby, Truls Eivind; Kanas, Nikola (Peer reviewed; Journal article, 2020)
      An all-oxide thermoelectric generator for high-temperature operation depends on a low electrical resistance of the direct p–n junction. Ca3Co4−xO9+δ and CaMnO3−δ exhibit p-type and n-type electronic conductivity, respectively, ...
    • Chemical tracer diffusion of Sr and Co in polycrystalline Ca-deficient CaMnO3-δ with CaMn2O4 precipitates 

      Desissa, Temesgen D.; Kanas, Nikola; Singh, Sathya Prakash; Wiik, Kjell; Einarsrud, Mari-Ann; Norby, Truls Eivind (Journal article; Peer reviewed, 2018)
      Diffusivity on the A- and B-site of polycrystalline perovskite CaMnO3-δ with Ca deficiency and spinel CaMn2O4 (marokite) as a secondary phase was studied using chemical tracers and secondary ion mass spectrometry (SIMS) ...
    • Development and ceramic processing of all-oxide thermoelectric module with direct p-n junction 

      Kanas, Nikola (Doctoral theses at NTNU;2018:91, Doctoral thesis, 2018)
    • Influence of processing on stability, microstructure and thermoelectric properties of Ca3Co4-xO9+δ 

      Kanas, Nikola; Singh, Sathya Prakash; Rotan, Magnus; saleemi, Mohsin; Bittner, Michael; Feldhoff, Armin; Norby, Truls Eivind; Wiik, Kjell; Grande, Tor (Journal article; Peer reviewed, 2018)
      Due to high figure of merit, Ca3Co4-xO9+δ (CCO) has potential as p-type material for high-temperature thermoelectrics. Here, the influence of processing including solid state sintering, spark plasma sintering and ...
    • Long term stability testing of oxide unicouple thermoelectric modules 

      Skomedal, Gunstein; Vehus, Tore; Kanas, Nikola; Singh, Sathya Prakash; Einarsrud, Mari-Ann; Wiik, Kjell; Middleton, Peter Hugh (Journal article; Peer reviewed, 2019)
      Thermoelectric devices based on oxides are good candidates for energy harvesting technologies for use in aggressive conditions where the materials should withstand high temperatures and corrosive environments over prolonged ...
    • Performance of a thermoelectric module based on n-type (La0.12Sr0.88)0.95TiO3-δ and p-type Ca3Co4-xO9+δ 

      Kanas, Nikola; Skomedal, Gunstein; Desissa, Temesgen D.; Feldhoff, Armin; Grande, Tor; Wiik, Kjell; Einarsrud, Mari-Ann (Journal article; Peer reviewed, 2020)
      Here, we present the performance of a thermoelectric (TE) module consisting of n-type (La0.12Sr0.88)0.95TiO3 and p-type Ca3Co4-xO9+δ materials. The main challenge in this investigation was operation of TE module in different ...
    • Tailoring the electrical conductivity and hardening in BiFeO3 ceramics 

      Makarovič, Maja; Kanas, Nikola; Zorko, A.; Ziberna, K.; Ursic, H.; Småbråten, Didrik Rene; Selbach, Sverre Magnus; Tadej, Rojac (Peer reviewed; Journal article, 2020)
      In this report, the influence of cobalt doping and annealing atmosphere on the electrical conductivity and polarization switching of BiFeO3 (BFO) ceramics was studied. Electrical conductivity as well as hardening behavior ...
    • Thermoelectric properties of A-site deficient La-doped SrTiO3 at 100–900 °C under reducing conditions 

      Singh, Sathya Prakash; Kanas, Nikola; Desissa, Temesgen Debelo; Johnsson, Mats; Einarsrud, Mari-Ann; Norby, Truls Eivind; Wiik, Kjell (Journal article; Peer reviewed, 2019)
      Lanthanum doped strontium titanate is a potential n-type thermoelectric material at moderate and high temperatures. (La0.12Sr0.88)0.95TiO3 ceramics were prepared by two different routes, conventional sintering at 1500 °C ...
    • Thermoelectric Properties of Ca3Co2−xMnxO6 (x = 0.05, 0.2, 0.5, 0.75, and 1) 

      Kanas, Nikola; Singh, Sathya Prakash; Rotan, Magnus; Desissa, Temesgen Debelo; Grande, Tor; Wiik, Kjell; Norby, Truls Eivind; Einarsrud, Mari-Ann (Journal article; Peer reviewed, 2019)
      High-temperature instability of the Ca3Co4−yO9+δ and CaMnO3−δ direct p-n junction causing the formation of Ca3Co2−xMnxO6 has motivated the investigation of the thermoelectric performance of this intermediate phase. Here, ...
    • Thermoelectric properties of non-stoichiometric CaMnO3-d composites formed by redox-activated exsolution. 

      Singh, Sathya Prakash; Kanas, Nikola; Desissa, Temesgen Debelo; Einarsrud, Mari-Ann; Norby, Truls Eivind; Wiik, Kjell (Journal article; Peer reviewed, 2019)
      A novel synthesis route for preparing well-defined composites based on CMO (CaMnO3) has been established taking advantage of the unique phase relations in the system Ca-Mn-O at reducing- and oxidizing atmosphere, respectively. ...
    • Triple-phase ceramic 2D nanocomposite with enhanced thermoelectric properties 

      Bittner, Michael; Kanas, Nikola; Hinterding, Richard; Steinbach, Frank; Groeneveld, Dennis; Wemhoff, Piotr; Wiik, Kjell; Einarsrud, Mari-Ann; Feldhoff, Armin (Journal article; Peer reviewed, 2019)
      A thermoelectric triple-phase p-type Ca3Co4O9-NaxCoO2-Bi2Ca2Co2O9 (CCO–NCO–BCCO) 2D nanocomposite was obtained from pressureless sintering in air. The anisotropic thermoelectric properties of the nanocomposite exhibit a ...