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Memorias de investigación
Communications at congresses:
Band gap control by tuning inversion degree in CdIn2S4 spinel
Research Areas
  • Chemistry,
  • Electric engineers, electronic and automatic (eil),
  • Materials for electric engineering and electronics,
  • Technology of devices for engineering
The composition of CdIn2S4 spinel is (Cd{1-x}Inx)[In2-xCdx]S4 having in the perfectly direct spinel, Cd and In respectively in the tetrahedral and octahedral positions. The experimental value of inversion degree is around x=0.20 then CdIn2S4 is almost considered a direct spinel. Our work focuses on the tetrahedral/octahedral cation inversion inside CdIn2S4 spinel using a thermodynamical analysis and the Site Occupancy Disorder (SOD) program, which have been a powerful tool to obtain the different inequivalent configurations of the disordered sites. We demonstrates using the thermodynamical parameters that CdIn2S4 have almost all their Cd/In in tetrahedral/octahedral cationic positions not exchanged and that the minimum of free energy correspond to an inversion which is coherent with the experimental value reported. The consistency of the obtained theoretical results in this work is accurately related with the previous experimental results. The present findings are proposed as a novel theoretical methodology to obtain the exact degree of inversion in the not so few different spinels. Using the appropriate inversion degree the band-gap can be adjusted, with the corresponding applications in the optimization of some photovoltaic processes. Furthermore, the phonon frequencies to determine vibrational total energy, and the asignations of the active modes was also determined. The atomic configurational interaction using the configurational free energy contribution added to the vibrational free energy obtained gave us the complete theoretical approach to obtain the exact inversion degree. The change in temperature lead a change in the inversion degree which is related with the band-gap, then controlling temperature, the inversion degree can be tuned and we can also have a desirable value of band-gap of this promising photovoltaic material.
2012 Computational Condensed Matter Physics
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End Date
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Procc. of Mini Workshop 2012
  • Autor: Yohanna Seminóvski Pérez (UPM)
  • Autor: Pablo Palacios Clemente (UPM)
  • Autor: R. Grau-Crespo (Royal Society)
  • Autor: Perla Wahnon Benarroch (UPM)
Research Group, Departaments and Institutes related
  • Creador: Departamento: Física y Química Aplicadas a la Técnica Aeronáutica
  • Departamento: Tecnologías Especiales Aplicadas a la Telecomunicación
S2i 2020 Observatorio de investigación @ UPM con la colaboración del Consejo Social UPM
Cofinanciación del MINECO en el marco del Programa INNCIDE 2011 (OTR-2011-0236)
Cofinanciación del MINECO en el marco del Programa INNPACTO (IPT-020000-2010-22)