Characterization and photoluminescence properties of ultrafine copper molybdate (α-CuMoO₄) powders prepared via a combustion-like process

Abstract

We report a simple method for preparing copper(II) molybdate (CuMoO₄) powders via a combustion-like process. A gel was first prepared by the polymerizable complex method, where citric acid was used as a complexing and polymerizing agent and nitric acid was used as an oxidizing agent. The thermal decomposition behavior of the (CuMo)-precursor gel was studied by thermogravimetry–differential thermal analysis (TG–DTA), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). We observed that the crystallization of CuMoO₄ powder was completed at 450°C. The obtained homogeneous powder was composed of grains with sizes in the range from 150 to 500 nm and exhibited a specific surface area of approximately 5 m²/g. The average grain size increased with increasing annealing temperature. The as-prepared CuMoO₄ crystals showed a strong green photoluminescence emission at room temperature under excitation at 290 nm, which we mainly interpreted on the basis of the Jahn-Teller effect on [MoO₄ ²⁻] complex anions. We also observed that the photoluminescence intensity increased with increasing crystallite size.

Keywords

copper molybdate / chemical synthesis / photoluminescence / Jahn-Teller effect

References

[1] Ehrenberg H., Wiesmann M., Garcia-Jaca J., Weitzel H., Fuess H. Magnetic structures of the high-pressure modifications of CoMoO₄ and CuMoO₄. J. Magn. Magn. Mater., 1989, 182(1-2): 152.

[2] Ryu J.H., Koo S.M., Yoon J.W., Lim C.S., Shim K.B. Synthesis of nanocrystalline MMoO₄ (M=Ni,Zn) phosphors via a citrate complex route assisted by microwave irradiation and their photoluminescence. Mater. Lett., 2006, 60(13-14): 1702.

[3] Palacio L.A., Echavarría A., Sierra L., Lombardo E.A. Cu,Mn and Co molybdates derived from novel precursors catalyze the oxidative dehydrogenation of propane. Catal. Today, 2005, 107-108, 338.

[4] Lebukhova N.V., Rudnev V.S., Chigrin P.G., Lukiyanchuk I.V., Pugachevsky M.A., Ustinov A.Y., Kirichenko E.A., Yarovaya T.P. The nanostructural catalytic composition CuMoO₄/TiO₂ + SiO₂/Ti for combustion of diesel soot. Surf. Coat. Technol., 2013, 231, 144.

[5] Najafi M., Abbasi A., Masteri-Farahani M., Nunes V.H. Rodrigues,Synthesis,characterization and crystal structure of a copper molybdate coordination polymer as an epoxidation catalyst. Inorg. Chim. Acta, 2015, 433, 21.

[6] Wiesmann M., Ehrenberg H., Miehe G., Peun T., Weitzel H., Fuess H. p–T phase diagram of CuMoO₄. J. Solid State Chem., 1997, 132(1): 88.

[7] Ehrenberg H., Weitzel H., Paulus H., Wiesmann M., Wltschek G., Geselle M., Fuess H. Crystal structure and magnetic properties of CuMoO4 at low temperature (phase). J. Phys. Chem. Solids, 1997, 58(1): 153.

[8] Yanase I., Mizuno T., Kobayashi H. Structural phase transition and thermochromic behavior of synthesized W-substituted CuMoO₄. Ceram. Int., 2013, 39(2): 2059.

[9] Gaudon M., Carbonera C., Thiry A.E., Demourgues A., Deniard P., Payen C., Létard J.F., Jobic S. Adaptable thermochromism in the CuMo1–xWxO₄ series (0 ≤ x < 0.1): a behavior related to a first-order phase transition with a transition temperature depending on x. Inorg. Chem., 2007, 46(24): 10200.

[10] Rathore D., Kurchania R., Pandey R.K. Influence of particle size and temperature on the dielectric properties of CoFe2O4 nanoparticles. Int. J. Miner. Metall. Mater., 2014, 21(4): 408.

[11] Ebin B., Arig E., Özkal B., Gürmen S. Production and characterization of ZnO nanoparticles and porous particles by ultrasonic spray pyrolysis using a zinc nitrate precursor. Int. J. Miner. Metall. Mater., 2012, 19(7): 651.

[12] Yuan P., Fan C., Ding G., Wang Y., Zhang X. Preparation and photocatalytic properties of ilmenite NiTiO₃ powders for degradation of humic acid in water. Int. J. Miner. Metall. Mater., 2012, 19(4): 372.

[13] Abbas F., Iqbal J., Jan T., Badshah N., Mansoor Q., Ismail M. Structural, morphological, Raman, optical, magnetic, and antibacterial characteristics of CeO₂ nanostructures. Int. J. Miner. Metall. Mater., 2016, 23(1): 102.

[14] Polak K., Nikl M., Nitsch K., Kobayashi M., Ishii M., Usuki Y., Jarolimek O. The blue luminescence of PbWO₄ single crystals. J. Lumin., 1997, 72-74, 781.

[15] Lim C.S. Microwave-assisted synthesis and photoluminescence of MMoO₄ (M=Ca, Ba) particles via a metathetic reaction. J. Lumin., 2012, 132(7): 1774.

[16] Yoon J.W., Ryu J.H., Shim K.B. Photoluminescence in nanocrystalline MMoO₄ (M = Ca,Ba) synthesized by a polymerized complex method. Mater. Sci. Eng. B, 2006, 127(2-3): 154.

[17] Sczancoski J.C., Cavalcante L.S., Marana N.L., da Silva R.O., Tranquilin R.L., Joya M.R., Pizani P.S., Varela J.A., Sambrano J.R., Siu Li M., Longo E., Andrés J. Electronic structure and optical properties of BaMoO₄ powders. Curr. Appl. Phys., 2010, 10(2): 614.

[18] Xing G.J., Liu R., Zhao C., Li Y.L., Wang Y., Wu G.M. Photoluminescence and photocatalytic properties of uniform PbMoO4 polyhedral crystals synthesized by microemulsion-based solvothermal method. Ceram. Int., 2011, 37(7): 2951.

[19] Wu X., Du J., Li H., Zhang M., Xi B., Fan H., Zhu Y., Qian Y. Aqueous mineralization process to synthesize uniform shuttle-like BaMoO₄ microcrystals at room temperature. J. Solid State Chem., 2007, 180(11): 3288.

[20] Campos A.B., Simões A.Z., Longo E., Varela J.A., Longo V.M., de Figuerido A.T., De Vicente F.S., Hernandes A.C. Mechanisms behind blue, green, and red photoluminescence emissions in CaWO₄ and CaMoO₄ powders. Appl. Phys. Lett., 2007, 91, 051923.

[21] Amir Md., Baykal A., Güner S., Sertkol M., Sözeri H., Toprak M. Synthesis and characterization of CoxZn1-xAlFeO4 nanoparticles. J. Inorg. Organomet. Polym. Mater., 2015, 25(4): 747.

[22] Bai Y., Lu L., Bao J. Synthesis and characterization of lanthanum zirconate nanocrystals doped with iron ions by a salt-assistant combustion method. J. Inorg. Organomet. Polym. Mater., 2011, 21(3): 590.

[23] Zhang H., Jia X., Liu Z., Li Z. The low temperature preparation of nanocrystalline MgAl₂O₄ spinel by citrate sol-gel process. Mater. Lett., 2004, 58(10): 1625.

[24] Vivekanandhan S., Venkateswarlu M., Satyanarayana N. Novel urea assisted polymeric citrate route for the synthesis of nanocrystalline spinel LiMn₂O₄ powders. J. Alloys Compd., 2007, 441(1-2): 284.

[25] Sivakumar M., Kanagesan S., Chinnaraj K., Suresh Babu R., Nithiyanantham S. Synthesis,Characterization and effects of citric acid and PVA on magnetic properties of CoFe₂O₄. J. Inorg. Organomet. Polym. Mater., 2013, 23(2): 439.

[26] Gharagozlou M. Synthesis, characterization and influence of calcination temperature on magnetic properties of nanocrystalline spinel Co-ferrite prepared by polymeric precursor method. J. Alloys Compd., 2009, 486(1-2): 660.

[27] Ramaswamy S., Umadevi M., Rajaram R.K., Ramakrishnan V. Infrared and Raman spectral studies of L-ornithine nitrate. J. Raman Spectrosc., 2003, 34(10): 806.

[28] Klissurski D., Iordanova R., Milanova M., Radev D., Vassilev S. Mechanochemically assisted synthesis of Cu(II) molybdate. CR Acad. Bulgare Sci., 2003, 56(8): 39.