Journal of Sol-Gel Science and Technology

, Volume 67, Issue 2, pp 321–330 | Cite as

Sol–gel synthesis, crystal structure, electronic properties and magnetic studies of B2+xAsxCo4−3xO7 (0.0 ≤ x ≤ 0.75) composites

Original Paper


Synthesis of B2+xAsxCo4−3xO7 (S1–S4: x = 0.0, 0.25, 0.50 and 0.75) composite oxides were performed by sol–gel method. The powder X-ray diffraction pattern and Reitveld refinement results revels that the samples are formed monoclinic phase with Z = 2 and space group P21/m. Average crystallite size of the samples determined by Scherrer’s relation are found to be ~28–50 nm. The observed and calculated density values are determined and compared. Thermogram shows no phase transition in the range of 50–1,000 °C. The scanning electron micrographs show the morphology of the samples which are observed, the crystallites are rod like shape. The purity and the quantitative analysis were examined by the energy dispersive X-ray. The B–O and Co–O bonds of different sites show marginal variation in the samples, the circular valence charge density contour map of the Co and O in S1–S4 show partial covalent nature of Co–O. Based on the plane-wave density functional theory calculations on crystal structure for band structure and density of states of sample S1–S4 using CASTEP programme package show all the samples are conductor with no band gap. The magnetic moment plot in the range ±10 kG indicates the weak ferromagnetic behavior of the samples. The electron paramagnetic resonance line shapes of all four (S1–S4) samples are isotropic, Diffuse reflectance spectra of sample S1–S4 at room temperature show the band around 273 nm is ligand to metal (O2− → Co2+) charge transfer transition and d–d transition around 570 nm, respectively.


Sol–gel synthesis Composite oxides Powder XRD Rietveld refinement Electronic band structure Density of states EPR 



The authors thank Dr. M. M. Balakrishnarajan, for help with the Materials Studio software and Central Instrumentation Facility, Pondicherry University, Puducherry.


  1. 1.
    Aronne A, Turco M, Bagnasco G, Pernice P, Di Serio M, Clayden NJ, Marenna E, Fanelli E (2005) Chem Mater 17:2081–2090CrossRefGoogle Scholar
  2. 2.
    Gubin SP, Koksharov YuA, Khomutov GB, Yurkov GYu (2005) Russ Chem Rev 74:489–520CrossRefGoogle Scholar
  3. 3.
    Massard C, Taverdet JL, Brouillet S, Donnet C (2007) Surf Coat Technol 202:1067–1072CrossRefGoogle Scholar
  4. 4.
    Praveena K, Sadhana K, RamanaMurthy S (2011) J Magn Magn Mater 323:2122–2128CrossRefGoogle Scholar
  5. 5.
    McHenry ME, Laughhlin DE (2000) Acta Mater 48:223–238CrossRefGoogle Scholar
  6. 6.
    Keshmiria M, Troczynskia T, Mohsenib M (2006) J Hazard Mater 128:130–137CrossRefGoogle Scholar
  7. 7.
    Muggli DS, McCue JT, Falconer JL (1998) J Catal 173:470–483CrossRefGoogle Scholar
  8. 8.
    Nishimoto BSI, Ohtani B, Kajiwara H, Kagiya T (1985) J Chem Soc Faraday Trans 1(81):61–68Google Scholar
  9. 9.
    Walker SA, Christensen PA, Shaw KE, Walker GM (1995) J Electroanal Chem 393:137–140CrossRefGoogle Scholar
  10. 10.
    Zayat Marcos, Levy David (2000) Chem Mater 12:2763–2769CrossRefGoogle Scholar
  11. 11.
    Gill SK, Shobe AM, Hope-weeks LJ (2009) Scanning 31:132–138CrossRefGoogle Scholar
  12. 12.
    Xu J, Zhao Y, Kuang Q (2011) J Sol–Gel Sci Technol 58:1–4CrossRefGoogle Scholar
  13. 13.
    Rietveld HM (1969) J Appl Crystallogr 2:65–71CrossRefGoogle Scholar
  14. 14.
    Garbout A, Bouattour S, Botelho do Rego AM, Ferraria A, Kolsia AW (2007) J Cryst Growth 304:374–378CrossRefGoogle Scholar
  15. 15.
    Das BB, Ambika R (2010) Indian J Chem Sect A 49:425–430Google Scholar
  16. 16.
    Carvajal JR, Hennion M, Moussa F, Moudden AH (1998) Phys Rev B 57:R3189–R3192CrossRefGoogle Scholar
  17. 17.
    Pakokthom C, Rujijanagul G, Tunkasiri T (1999) J Mater Sci Lett 18:747–749CrossRefGoogle Scholar
  18. 18.
    Chen DG, Cheng WD, Wu DS, Zhang H, Zhang YC, Gong YJ, Kan ZG (2004) J Solid State Chem 177:3927–3933CrossRefGoogle Scholar
  19. 19.
    Hamann DR, Schluter M, Chiang C (1979) Phys Rev Lett 43:1494–1497CrossRefGoogle Scholar
  20. 20.
    Segall MD, Lindan PLD, Probert MJ, Pickard CJ, Hasnip PJ, Clark SJ, Payne MC (2002) J Phys Condens Mater 14:2717–2745CrossRefGoogle Scholar
  21. 21.
    McMillan AS, Broadbelt JL, Snurr QR (2002) J Phys Chem B 106:10864–10872CrossRefGoogle Scholar
  22. 22.
    Oleinik II, Tsymbal EY, Pettifor DG (2000) Phys Rev B 16:1–9Google Scholar
  23. 23.
    Jauch W, Reehuis M (2002) Phys Rev B 65:125111–125118CrossRefGoogle Scholar
  24. 24.
    Wang L, Wang Y, Wang D, Zhang J (2008) Solid State Commun 148:331–335CrossRefGoogle Scholar
  25. 25.
    Ensling D, Thissen A, Laubach S, Schmidt PC, Jaegermann W (2010) Phys Rev B 82:195431-16CrossRefGoogle Scholar
  26. 26.
    Jiang XM, Xu ZN, Zhao ZY, Guo SP, Guo GC, Huang JS (2011) Eur J Inorg Chem 26:4069–4076CrossRefGoogle Scholar
  27. 27.
    Brahma P, Anit K, Giri Chakravorty D (1992) J Magn Magn Mater North-Holland 117:163–168CrossRefGoogle Scholar
  28. 28.
    Kumar L, Kar M (2011) J Magn Magn Mater 323:2042–2048CrossRefGoogle Scholar
  29. 29.
    Bai Y, Zhou J, Gui Z, Yue Z, Li L (2003) Mate Sci Eng B 99:266–269CrossRefGoogle Scholar
  30. 30.
    Duan XL, Yuan DR, Wanga LH, Yu FP, Cheng XF, Liu ZQ, Yan SS (2006) J Cryst Growth 296:234–238CrossRefGoogle Scholar
  31. 31.
    Carta G, Casarin M, El Habra N, Natali M, Rossetto G, Sada C, Tondello E, Zanella P (2005) Electrochim Acta 50:4592–4599CrossRefGoogle Scholar
  32. 32.
    Rangappa D, Ohara S, Naka T, Kondo A, Ishiib M, Adschiri T (2007) J Mater Chem 17:4426–4429CrossRefGoogle Scholar
  33. 33.
    Yang H, Zhang B, Wang X, Wang X, Li T, Xie S, Yao X (2005) J Cryst Growth 280:521–529CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  1. 1.Materials Chemistry Laboratory, Department of ChemistryPondicherry UniversityPuducherryIndia

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