Journal of Thermal Analysis and Calorimetry

, Volume 119, Issue 1, pp 175–182 | Cite as

Thermal stability and structural properties of Ta nanopowder synthesized via simultaneous reduction of Ta2O5 by hydrogen and carbon

  • Loveleen K. Brar
  • Gourav Singla
  • Navjot Kaur
  • O. P. Pandey


Tantalum nanoparticles have been synthesized by the single-step chemical reaction route. Simultaneous reduction of Tantalum Pentoxide (Ta2O5) with the in situ produced hydrogen and carbon at 600 °C is a new approach for the production of Ta nanopowder. ΔH values obtained from thermodynamic calculations are used to predict the entire mechanism of reduction of bulk Ta2O5 into Ta nanoparticles. The results of X-ray diffraction studies show that the final product consists of predominately nano α-Ta with β-Ta as the minority phase. The lattice strain in the final product was calculated using Williamson–Hall formula. The effect of lattice strain on thermal stability of the samples was analyzed by differential scanning calorimetry and thermal gravimetry in the air atmosphere. The morphology and particle size distribution of Ta nanosized powders have been analyzed by scanning electron microscope and transmission electron microscope. The results show that average crystallite size of the product Ta nanopowder is about 2–7 nm.


Nanoparticles Tantalum α-Ta β-Ta Chemical reaction method 



One of the author (O. P. Pandey) is thankful to Department of Science and Technology (DST), New Delhi, India for which proposal has been submitted. The authors are also grateful to Central Research facilities (IIT Ropar) for providing XRD, IIT Roorkee for providing FE-SEM, SAI Labs, Thapar University for providing SEM and AIIMS, Delhi for providing TEM.


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Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2014

Authors and Affiliations

  • Loveleen K. Brar
    • 1
  • Gourav Singla
    • 1
  • Navjot Kaur
    • 1
  • O. P. Pandey
    • 1
  1. 1.School of Physics and Materials ScienceThapar UniversityPatialaIndia

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