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Preparation, optical, and photocatalytic studies of defect pyrochlores: KCr0.33W1.67O6 and A x Cr0.33W1.67O6·nH2O

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Abstract

Nano sized defect pyrochlores of compositions KCr0.33W1.67O6 and A x Cr0.33W1.67O6·nH2O (A = Sn, Ag, Bi, Sm, Eu, and Gd) have been synthesized by sol–gel and ion exchange methods, respectively. These oxides were characterized by thermogravimetric analysis, powder X-ray diffraction, energy dispersive spectra, transmission electron microscopy, UV–Vis diffuse reflectance spectra, Raman spectra, and Fourier transform infrared spectra. Spontaneous exchange of K+ with A ion is accompanied by insertion of water also into the lattice. KCr0.33W1.67O6 and A x Cr0.33W1.67O6·nH2O crystallize in cubic lattice and isomorphous with KSbWO6. The optical properties of Cr3+ were investigated. Substitution of K+ by A ion leads to a shift of absorption onset to longer wavelengths marginally. The Raman spectra of all the samples are characteristic of defect pyrochlore system. The photocatalytic degradation of methylene blue aqueous solution was investigated using these oxides. The results obtained were fitted with the Langmuir–Hinshelwood model to study the degradation kinetics. Both Sn2+ and Bi3+-doped KCr0.33W1.67O6 exhibit higher photoactivity in the degradation of methylene blue. The structure/composition of the photocatalyst remains the same even after fourth cycle of photodegradation.

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References

  • Avdeev M, Haas MK, Jorgensen JD, Cava RJ (2002) Static disorder from lone-pair electrons in Bi2−x M x Ru2O7−y (M = Cu, Co; x = 0, 0.4) pyrochlores. J Solid State Chem 169:24–34

    Article  Google Scholar 

  • Borgarello E, Kiwi J, Gratzel M, Pelizzetti E, Viscald M (1982) Visible light induced water cleavage in colloidal solutions of chromium-doped titanium dioxide particles. J Amer Chem Soc 104:2996–3002

    Article  Google Scholar 

  • Brown S, Gupta HC, Alonso JA, Martinez-lope MJ (2004) Lattice dynamical study of optical modes in Tl2Mn2O7 and In2Mn2O7 pyrochlores. Phys Rev B 69:054434

    Article  Google Scholar 

  • Campet G, Jakani M, Doumerc JP, Claverie J, Hagenmuller P (1982) Photoconduction mechanisms in titanium and rare earth n-type semiconducting electrodes with pyrochlore and perovskite structures. Solid State Commun 42:93–96

    Article  Google Scholar 

  • Debnath T, Roy SC, Ruscher CH, Hussain A (2009) Synthesis and characterization of niobium-doped potassium tetragonal tungsten bronzes, K x Nb y W1−y O3. J Mater Sci 44:179–185

    Article  Google Scholar 

  • Digeos AA, Valdez JA, Sickafus KE, Atiq S, Grimes RW, Boccaccini AR (2003) Glass matrix/pyrochlore phase composites for nuclear wastes encapsulation. J Mater Sci 38:1597–1604

    Article  Google Scholar 

  • Eberman KW, Wuensch BJ, Jorgensen JD (2002) Order–disorder transformations induced by composition and temperature change in (Sc z Yb1−z )2Ti2O7 pyrochlores, prospective fuel cell materials. Solid State Ionics 148:521–526

    Article  Google Scholar 

  • Fuertes JR, Errandonea D, Moreno SL, González J, Gomis O, Vilaplana R, Manjón FJ, Muñoz A, Hernández PR, Friedrich A, Tupitsyna IA, Nagornaya LL (2011) High-pressure Raman spectroscopy and lattice-dynamics calculations on scintillating MgWO4: comparison with isomorphic compounds. Phys Rev B 83:214112

    Article  Google Scholar 

  • Gupta HC, Rani N (2007) A lattice dynamical investigation of the Raman and the infrared frequencies of the cubic Y2Ru2O7 pyrochlore. J Phys Chem Solids 68:1293–1295

    Article  Google Scholar 

  • Hasegawa T, Takasu Y, Ogita N, Udagawa M, Yamaura JI, Nagao Y, Hiroi Z (2008) Raman scattering in KOs2O6. Phys Rev B 77:064303

    Article  Google Scholar 

  • Hasegawa T, Takasu Y, Ogita N, Yamaura J, Nagao Y, Hiroi Z, Udagawa M (2009) Raman scattering investigation of β-pyrochlore osmium oxides, AOs2O6 (A = K, Rb, and Cs). J Phys Conf Ser 150:052067

    Article  Google Scholar 

  • Henderson B, Imbush GF (1989) Optical spectroscopy of inorganic crystals. Oxford University Press, Oxford

    Google Scholar 

  • Ji Y, Kilner JA, Carolan MF (2005) Electrical properties and oxygen diffusion in yttria-stabilised zirconia (YSZ)–La0.8Sr0.2MnO3±δ (LSM) composites. Solid State Ionics 176:937–943

    Article  Google Scholar 

  • Kako T, Zou Z, Ye J (2005) Photocatalytic oxidation of 2-propanol in the gas phase over cesium bismuth niobates under visible light irradiation. Res Chem Intermed 31:359–364

    Article  Google Scholar 

  • Kennedy J, Vogt T (1996) Structural and bonding trends in ruthenium pyrochlores. J Solid State Chem 126:261–270

    Article  Google Scholar 

  • Kharton VV, Naumovich EN, Nikolaev AV (1996) Materials of high-temperature electrochemical oxygen membranes. J Membr Sci 111:149–157

    Article  Google Scholar 

  • Knyazev AV, Yu Kuznetsova N (2009) Crystal structure of compounds CsAVA′VIO6(AV = Sb, Ta; A′VI = W, U). Radiochem 51:1–4

    Article  Google Scholar 

  • Knyazev AV, Maczka M, kuznetsova NY (2010) Thermodynamic modeling, structural and spectroscopic studies of the KNbWO6–KSbWO6–KTaWO6 system. Thermochim Acta 506:20–27

    Article  Google Scholar 

  • Kudo A, Hijii S (1999) H2 or O2 Evolution from aqueous solutions on layered oxide photocatalysts consisting of Bi3+ with 6s2 configuration and d0 transition metal ions. Chem Lett 10:1103–1104

    Article  Google Scholar 

  • Kudo A, Kato H, Nakagawa S (2000) Water splitting into H2 and O2 on new Sr2M2O7 (M = Nb and Ta) photocatalysts with layered perovskite structures: factors affecting the photocatalytic activity. J Phys Chem B 104:571–575

    Article  Google Scholar 

  • Long X, Lin Z, Hu Z, Wang G, Han TPJ (2002) Optical study of Cr3+-doped LaSc3(BO3)4 crystal. J Alloy Compd 347:52–55

    Article  Google Scholar 

  • Luan J, Zhao W, Feng J, Cai H, Zheng Z, Pan B, Wu X, Zou Z, Li Y (2009) Structural, photophysical and photocatalytic properties of novel Bi2AlVO7. J Hazard Mat 164:781–789

    Article  Google Scholar 

  • Machida M, Yabunaka J, Kijima T (2000) Synthesis and photocatalytic property of layered perovskite tantalates, RbLnTa2O7 (Ln = La, Pr, Nd, and Sm). Chem Mater 12:812–817

    Article  Google Scholar 

  • Machida M, Yabunaka J, Kijima T (2001) Photocatalytic Property and electronic structure of lanthanide tantalates, LnTaO4(Ln = La, Ce, Pr, Nd, and Sm). J Phys Chem B 105:3289–3294

    Article  Google Scholar 

  • Maczka M, Hanuza J, Majchrowski A (2001) Vibrational properties of ferroelectric hexagonal tungsten bronzes AB x W3−x O9, where A = K, Rb, Cs and B = Nb, Ta, Zr, Cr. J Raman Spectrosc 32:929–936

    Article  Google Scholar 

  • Maczka M, Paragassu W, Filho AGS, Freiro PTc, Filho JM, Melo FEA, Hanuza J (2004) High-pressure Raman study of Al2(WO4)3. J Solid State Chem 177:2002–2006

    Article  Google Scholar 

  • Maczka M, Sanjuam ML, Fuentes AF, Macalik L, Hanuza J, Matsuhira K, Hiroi Z (2009) Lattice dynamical study of optical modes in Tl2Mn2O7 and In2Mn2O7 pyrochlores. Phys Rev B 79:214437

    Article  Google Scholar 

  • Maczka M, Knyazev AV, Yu Kuznetsova N, Ptak M, Macalik L (2011a) Raman and IR studies of TaWO5.5, ASbWO6 (A = K, Rb, Cs, Tl), and ASbWO6·H2O (A = H, NH4, Li, Na) pyrochlore oxides. J Raman Spectrosc 42:529–533

    Article  Google Scholar 

  • Maczka M, Ptak M, Hermanowicz K, Majchrowski A, Pikul A, Hanuza J (2011b) Lattice dynamics and temperature-dependent Raman and infrared studies of multiferroic Mn0.85Co0.15WO4 and Mn0.97Fe0.03WO4 crystals. Phys Rev B 83:174439

    Article  Google Scholar 

  • Maczka M, Filho AGS, Paraguassu W, Freire PTC, Filho JM, Hanuza J (2012a) Pressure-induced structural phase transitions and amorphization in selected molybdates and tungstates. Prog Mater Sci 57:1335–1381

    Article  Google Scholar 

  • Maczka M, Knyazev AV, Majchrowski A, Hanuza J, Kojima S (2012b) Temperature-dependent Raman scattering study of the defect pyrochlores RbNbWO6 and CsTaWO6. Phys Condens Matter 24:195902

    Article  Google Scholar 

  • Marschall R, Soldat J, Wark M (2013) Enhanced photocatalytic hydrogen generation from barium tantalate composites. Photochem Photobiol Sci 12:671–677

    Article  Google Scholar 

  • Michel C, Groult D, Raveau B (1973) Sur de nouveaux pyrochlores ASbWO6 (A = K, Rb, Cs, Tl). Mat Res Bull 8:201–210

    Article  Google Scholar 

  • Mims CA, Jacobson AJ, Hall RB, Lewandowski JT (1995) Methane oxidative coupling over nonstoichiometric bismuth–tin pyrochlore catalysts. J Catal 153:197–207

    Article  Google Scholar 

  • Mizoguchi H, Sleight AW, Subramanian MA (2009) Low temperature synthesis and characterization of SnTa2O6. Mater Res Bull 44:1022–1024

    Article  Google Scholar 

  • Moller T, Clearfield A, Harjula R (2002) Preparation of hydrous mixed metal oxides of Sb, Nb, Si, Ti and W with a pyrochlore structure and exchange of radioactive cesium and strontium ions into the materials. Microporous Mesoporous Mater 54:187–199

    Article  Google Scholar 

  • Orton JW (1968) An introduction to transition group ions in crystals. ILIFFE Book Ltd, London

    Google Scholar 

  • Perales RL, Errandonea R, Garcia DM, Hernandez DR, Radescu S, Mujica A, Munoz A, Chervin JC, Polian A (2009) Phase transitions in wolframite-type CdWO4 at high pressure studied by Raman spectroscopy and density-functional theory. Phys Rev B 79:094105

    Article  Google Scholar 

  • Ravi G, Palla S, Reddy JR, Veldurthi NK, Vijaya Kumar B, Vithal M (2012) Photocatalytic and conductivity studies of Bi3+ substituted La2Zr2O7. Int J Green Nanotechnol 4:360–367

    Article  Google Scholar 

  • Ravi G, Veldurthi NK, Palla S, Velchuri R, Pola S, Vithal M (2013) Synthesis, characterization and photocatalytic activity of KAl0.33W1.67O6 and Sn0.5Al0.33W1.67O6·xH2O. Photochem Photobiol 89:824–831

    Article  Google Scholar 

  • Schoenes J, Racu AM, Doll K, Bukowski Z, Karpinski J (2008) Phonons and crystal structures of the β-pyrochlore superconductors KOs2O6 and RbOs2O6 from micro-Raman spectroscopy. Phys Rev B 77:134515

    Article  Google Scholar 

  • Sohn JM, Kim MR, Woo SI (2003) The catalytic activity and surface characterization of Ln2B2O7 (Ln = Sm, Eu, Gd and Tb; B = Ti or Zr) with pyrochlore structure as novel CH4 combustion catalyst. Catal Today 83:289–297

    Article  Google Scholar 

  • Subramanian MA, Aravamudan G, SubbaRao GV (1983) Oxide pyrochlores—a review. Prog Solid State Chem 15:55–143

    Article  Google Scholar 

  • Subramanian MA, Toby BH, Ramirez AP, Marshall WJ, Sleight AW, Kwei GH (1996) Colossal magnetoresistance without Mn3+/Mn4+ double exchange in the stoichiometric pyrochlore Tl2Mn2O7. Science 273:81–84

    Article  Google Scholar 

  • Talebian N, Nilforoushan MR (2012) Comparative study of the structural, optical and photocatalytic properties of semiconductor metal oxides toward degradation of methylene blue. Thin Solid Films 518:2210–2215

    Article  Google Scholar 

  • Tanabe Y, Sugano S (1954) On the absorption spectra of complex ions. J Phys Soc Jpn 9:753–766

    Article  Google Scholar 

  • Tang X, Ye H, Liu H, Ma C, Zhao Z (2010) Photocatalytic splitting of water under visible-light irradiation over the NiO x -loaded Sm2InTaO7 with 4f d 10–d 0 configuration. J Solid State Chem 183:192–197

    Article  Google Scholar 

  • Tong H, Bi SO, Umezawa N, Oshikiri M, Ye J (2012) Nano-photocatalytic materials: possibilities and challenges. Adv Mater 24:229–251

    Article  Google Scholar 

  • Uno M, Kosuga A, Okui M, Horisaka K, Yamanaka S (2005) Photoelectrochemical study of lanthanide titanium oxides, Ln2Ti2O7(Ln = La, Sm, and Gd). J Alloys Compd 400:270–275

    Article  Google Scholar 

  • Uno M, Kosuga A, Okui M, Horisaka K, Muta H, Kurosaki K, Yamanaka S (2006) Photoelectrochemical study of lanthanide zirconium oxides, Ln2Zr2O7(Ln = La, Ce, Nd and Sm). J Alloys Compd 420:291–297

    Article  Google Scholar 

  • Vassen R, Cao X, Tietz F, Basu D, Stover D (2000) Zirconates as new materials for thermal barrier coatings. J Am Ceram Soc 83:2023–2028

    Article  Google Scholar 

  • Vogel AI (1989) Textbook of quantitative chemical analysis. Longman Group Ltd, Harlow

    Google Scholar 

  • Weber WJ, Ewing RC (2000) Plutonium immobilization and radiation effects. Science 289:2051–2052

    Article  Google Scholar 

  • Yonezawa S, Muraoka Y, Matsushita Y, Hiroi Z (2004) Superconductivity in a pyrochlore-related oxide KOs2O6. J Phys Condens Matter 16:L9–L12

    Article  Google Scholar 

  • Zarbin AJG, Alves OL, Amarilla JM, Rojas RM, Rojo JM (1999) Silver antimonates with pyrochlore-like structure prepared by thermal treatment of silver proton-exchanged antimonic acid: formation process and structural characterization. Chem Mater 11:1652–1658

    Article  Google Scholar 

Download references

Acknowledgments

We acknowledge financial support from University Grants Commission (UGC), New Delhi for the Major Research Project (Grant No: 37-288/2009 (SR).

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Authors and Affiliations

  1. Department of Chemistry, Osmania University, Hyderabad, 500 007, India

    G. Ravi, Naveen Kumar Veldurthi & M. Vithal

  2. School of Chemistry, University of Hyderabad, Hyderabad, 500 046, India

    Muvva D. Prasad

  3. Centre for Materials Electronics Technology (C-MET), IDA, Phase-III, Cherlapally, HCL Post, Hyderabad, 500 051, India

    N. R. Muniratnam

  4. Department of Physics, Osmania University, Hyderabad, 500 007, India

    G. Prasad

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  1. G. Ravi
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  2. Naveen Kumar Veldurthi
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Correspondence to M. Vithal.

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11051_2013_1939_MOESM1_ESM.docx

TGA curves of KCW and ion exchanged products of KCW (Fig. S1), the observed d-line values along with KSbWO6 d–lines (Table S1), the atomic positions, including fractional coordinates of the oxygen, occupancies and R factors of KCW (Table S2), the calculated d-line values of ion exchanged products (Table S3), energy dispersive spectra of AgCW, BiCW, SmCW, EuCW, and GdCW (Fig. S2), HRTEM image and SAED pattern of AgCW, BiCW, SmCW, EuCW and GdCW (Fig. S3, S4, S5, S6, and S7, respectively), Fourier transformed Infrared spectra of all the samples (Fig. S8), UV–Vis absorption spectra of methylene blue before and after visible light irradiation in the presence of SnCW (Fig. S9), Fluorescence spectra of visible light irradiated SnCW suspensions in 3 mM terephthalic acid (λ excitation = 320 nm) (Fig. S10) and powder XRD pattern of the photocatalyst SnCW before and after MB degradation under the visible light irradiation (Fig. S11). (DOCX 1168 kb)

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Ravi, G., Veldurthi, N.K., Prasad, M.D. et al. Preparation, optical, and photocatalytic studies of defect pyrochlores: KCr0.33W1.67O6 and A x Cr0.33W1.67O6·nH2O. J Nanopart Res 15, 1939 (2013). https://doi.org/10.1007/s11051-013-1939-0

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