EPR study of the photoassisted formation of radicals on CeO2 nanoparticles employed for toluene photooxidation

EPR study of the photoassisted formation of radicals on CeO2 nanoparticles employed for toluene photooxidation. Herńandez-Alonso, D, M., Hungría, B, A., Martínez-Arias, A., Ferńandez-García, M., Coronado, M, J., Conesa, C, J., & Soria, J. Applied Catalysis B: Environmental, 50(3):167--175, Inst. de Catalisis y Petroleoquimica, CSIC, Campus Cantoblanco, 28049 Madrid, Spain, 2004.

Paper abstract bibtex

Photoactivated processes occurring upon UV illumination of CeO2 nanoparticles prepared from reverse microemulsions have been studied by means of EPR spectroscopy. Different experimental approaches have been employed aiming to determine the capability of the samples for the trapping of photogenerated charge carriers either in the absence or in the presence of external scavengers or spin-trapping agents (O2 or DMPO molecules). These results are discussed in connection with the photocatalytic activity obtained over the samples for toluene oxidation. Under the employed experimental conditions, hydroxyl and superoxide radicals are detected as main species resulting from hole and electron trapping, respectively, at the surface of the samples. The photocatalytic activity of the samples can be related to the efficiency in the charge separation processes, in accordance with EPR results of oxygen photoadsorption. However, the nature of the active species is uncertain since no correlation is found between the activities for generation of hydroxyl radicals, based on DMPO trapping EPR experiments, and the photooxidation rates. This suggests the direct involvement of holes or other type of hole-derived entities as active species. © 2004 Elsevier B.V. All rights reserved.

@article{ Hernandez-Alonso2004,
  abstract = {Photoactivated processes occurring upon UV illumination of CeO2 nanoparticles prepared from reverse microemulsions have been studied by means of EPR spectroscopy. Different experimental approaches have been employed aiming to determine the capability of the samples for the trapping of photogenerated charge carriers either in the absence or in the presence of external scavengers or spin-trapping agents (O2 or DMPO molecules). These results are discussed in connection with the photocatalytic activity obtained over the samples for toluene oxidation. Under the employed experimental conditions, hydroxyl and superoxide radicals are detected as main species resulting from hole and electron trapping, respectively, at the surface of the samples. The photocatalytic activity of the samples can be related to the efficiency in the charge separation processes, in accordance with EPR results of oxygen photoadsorption. However, the nature of the active species is uncertain since no correlation is found between the activities for generation of hydroxyl radicals, based on DMPO trapping EPR experiments, and the photooxidation rates. This suggests the direct involvement of holes or other type of hole-derived entities as active species. © 2004 Elsevier B.V. All rights reserved.},
  address = {Inst. de Catalisis y Petroleoquimica, CSIC, Campus Cantoblanco, 28049 Madrid, Spain},
  annote = {Cited By (since 1996): 39

Export Date: 15 January 2013

Source: Scopus

CODEN: ACBEE

doi: 10.1016/j.apcatb.2004.01.016

Language of Original Document: English

Correspondence Address: Martínez-Arias, A.; Inst. de Catalisis y Petroleoquimica, CSIC, Campus Cantoblanco, 28049 Madrid, Spain; email: amartinez@icp.csic.es

References: Peral, J.L., Ollis, D., (1992) J. Catal., 136, p. 554; 
Hoffman, M.R., Martin, S.T., Choi, W., Bahnemann, D.W., (1995) Chem. Rev., 95, p. 69; 
Linsebigler, A.L., Lu, G., Yates, J.T., (1995) Chem. Rev., 95, p. 735; 
Alberici, R.M., Jardim, W.F., (1995) Appl. Catal. B, 14, p. 55; 
Anpo, M., Takeuchi, M., (2003) J. Catal., 216, p. 505; 
Fuerte, A., Herń{a}ndez-Alonso, M.D., Maira, A.J., Martínez-Arias, A., Ferń{a}ndez-García, M., Conesa, J.C., Soria, J., Munuera, G., (2002) J. Catal., 212, p. 1; 
Ameen, M.M., Raupp, G.B., (1999) J. Catal., 184, p. 112; 
Fuerte, A., Herń{a}ndez-Alonso, M.D., Maira, A.J., Martínez-Arias, A., Ferń{a}ndez-García, M., Conesa, J.C., Soria, J., (2001) Chem. Commun., p. 2178; 
Maira, A.J., Yeung, K.L., Soria, J., Coronado, J.M., Belver, C., Lee, C.Y., Augugliaro, V., (2001) Appl. Catal. B, 29, p. 327; 
Morimoto, T., Tomonaga, H., Mitani, A., (1999) Thin Solids Films, 351, p. 61; 
Li, R., Yabe, S., Yamashita, M., Momose, S., Yoshida, S., Yin, S., Sato, T., (2002) Solid State Ion., 151, p. 235; 
Bamwenda, G.R., Sayama, K., Arakawa, H., (2000) J. Mol. Catal. a, 161, p. 105; 
Bamwenda, G.R., Uesigi, T., Abe, Y., Sayama, K., Arakawa, H., (2001) Appl. Catal. a, 205, p. 117; 
Chung, K.H., Park, D.C., (1996) Catal. Today, 30, p. 157; 
Lin, J., Yu, J.C., (1998) J. Photochem. Photobiol. a, 116, p. 63; 
Coronado, J.M., Maira, A.J., Martínez-Arias, A., Conesa, J.C., Soria, J., (2002) J. Photochem. Photobiol. a, 150, p. 213; 
Miyauchi, M., Nakajima, A., Watanabe, T., Hashimoto, K., (2002) Chem. Mater., 14, p. 2812; 
Harrison, R.M., (1995) Volatile Organic Compounds in the Atmosphere, , The Royal Society of Chemistry, Cambridge; 
Riegel, G., Bolton, J.R., (1995) J. Phys. Chem., 99, p. 4215; 
Soria, J., Martínez-Arias, A., Conesa, J.C., (1995) J. Chem. Soc., Faraday Trans., 91, p. 1669; 
Conesa, J.C., Ferń{a}ndez-García, M., Martínez-Arias, A., (2002) Catalysis by Ceria and Related Materials, p. 169. , A. Trovarelli (Ed.), Imperial College Press, London; 
Martínez-Arias, A., Ferń{a}ndez-García, M., Ballesteros, V., Salamanca, L.N., Conesa, J.C., Otero, C., Soria, J., (1999) Langmuir, 15, p. 4796; 
Grela, M.A., Coronel, M.E.J., Colussi, A.J., (1996) J. Phys. Chem., 100, p. 16940; 
Zhang, F., Chan, S., Spanier, J.E., Apak, E., Jin, Q., Robinson, R.D., Herman, I.P., (2002) Appl. Phys. Lett., 80, p. 127; 
Zhang, J., Ju, X., Wu, Z.Y., Liu, T., Hu, T.D., Xie, Y.N., Zhang, Z.L., (2001) Chem. Mater., 13, p. 4192; 
Finnie, K.S., Cassidy, D.J., Bartlett, J.R., Woolfrey, J.L., (2001) Langmuir, 17, p. 816; 
Tanaka, K., White, J., (1982) J. Phys. Chem., 86, p. 4708; 
Li, C., Sakata, Y., Arai, T., Domen, K., Maruya, K., Onishi, T., (1989) J. Chem. Soc., Faraday Trans. 1, 85, p. 929; 
Tsuhako, M., Ikeuchi, S., Matsuo, T., Motooka, I., Kobayashi, M., (1979) Bull. Chem. Soc. Jpn., 52, p. 1034; 
Martínez-Arias, A., Soria, J., Conesa, J.C., Seoane, X.L., Arcoya, A., Cataluña, R., (1995) J. Chem. Soc., Faraday Trans., 91, p. 1679; 
N̈{o}remberg, H., Briggs, G.A.D., (1997) Phys. Rev. Lett., 79, p. 4222; 
Conesa, J.C., (1995) Surf. Sci., 339, p. 337; 
Martínez-Arias, A., Ferń{a}ndez-García, M., Salamanca, L.N., Valenzuela, R.X., Conesa, J.C., Soria, J., (2000) J. Phys. Chem. B, 104, p. 4038; 
Coronado, J.M., Maira, A.J., Conesa, J.C., Yeung, K.L., Augugliaro, V., Soria, J., (2001) Langmuir, 17, p. 5368; 
Figaj, M., Becker, K.D., (2001) Solid State Ion., 141, p. 507; 
Howe, R.F., Gr̈{a}tzel, M., (1987) J. Phys. Chem., 91, p. 3906; 
Nakaoka, Y., Nosaka, Y., (1997) J. Photochem. Photobiol. a, 110, p. 299; 
Che, M., Tench, A.J., (1982) Adv. Catal., 31, p. 77; 
Dvoranov́{a}, D., Brezov́{a}, V., Mazur, M., Malati, M.A., (2002) Appl. Catal. B, 37, p. 91; 
Brezov́{a}, V., Stasko, A., Lapcik, L., (1991) J. Photochem. Photobiol. a, 59, p. 115; 
Janzen, E.G., Sankuratry, N., Kotake, Y., (1996) J. Magn. Reson., 111, p. 254; 
Gonź{a}lez, M.A., Howell, S.G., Sikdar, S.K., (1999) J. Catal., 183, p. 159; 
Li, C., Xin, Q., Guo, X., (1992) Catal. Lett., 12, p. 297; 
Yeung, K.L., Maira, A.J., Stolz, J., Hung, E., Ho, N.K., Wei, A.C., Soria, J., Yue, P.L., (2002) J. Phys. Chem. B, 106, p. 4608; 
Taborda, A.V., Brusa, M.A., Grela, M.A., (2001) Appl. Catal. a, 208, p. 419; 
Fuerte, A., Herń{a}ndez-Alonso, M.D., Iglesias-Juez, A., Martínez-Arias, A., Conesa, J.C., Soria, J., Ferń{a}ndez-García, M., (2003) Phys. Chem. Chem. Phys., 5, p. 2913; 
Haber, J., Tokarz, R., Witko, M., (1994) New Developments in Selective Oxidation, p. 739. , V. Cortés Corbeŕ{a}n, S. Vic Belĺ{o}n (Eds.), Elsevier, Amsterdam},
  author = {Herń{a}ndez-Alonso, M D and Hungría, A B and Martínez-Arias, A and Ferń{a}ndez-García, M and Coronado, J M and Conesa, J C and Soria, J},
  issn = {09263373 (ISSN) },
  journal = {Applied Catalysis B: Environmental},
  keywords = {Adsorption,Catalyst activity,CeO2,Cerium compounds,Charge carriers,DMPO spin-trap,EPR,Electron spin resonance spectroscopy,Electron trapping,Lethrinidae,Lighting,Microemulsions,Nanoparticles,Nanostructured materials,Phosphorus poisoning,Photoadsorption,Photocatalysis,Photooxidation,Photooxidation rates,Radicals,Superoxide,Toluene,Ultraviolet radiation,VOCs removal},
  number = {3},
  pages = {167--175},
  title = {{EPR study of the photoassisted formation of radicals on CeO2 nanoparticles employed for toluene photooxidation}},
  url = {https://www.scopus.com/inward/record.url?eid=2-s2.0-2342535623\&partnerID=40\&md5=160273b520d2dfa21c696aa2bd0ca1c7},
  volume = {50},
  year = {2004}
}

Downloads: 0

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Different experimental approaches have been employed aiming to determine the capability of the samples for the trapping of photogenerated charge carriers either in the absence or in the presence of external scavengers or spin-trapping agents (O2 or DMPO molecules). These results are discussed in connection with the photocatalytic activity obtained over the samples for toluene oxidation. Under the employed experimental conditions, hydroxyl and superoxide radicals are detected as main species resulting from hole and electron trapping, respectively, at the surface of the samples. The photocatalytic activity of the samples can be related to the efficiency in the charge separation processes, in accordance with EPR results of oxygen photoadsorption. However, the nature of the active species is uncertain since no correlation is found between the activities for generation of hydroxyl radicals, based on DMPO trapping EPR experiments, and the photooxidation rates. This suggests the direct involvement of holes or other type of hole-derived entities as active species. © 2004 Elsevier B.V. All rights reserved.},\n address = {Inst. de Catalisis y Petroleoquimica, CSIC, Campus Cantoblanco, 28049 Madrid, Spain},\n annote = {Cited By (since 1996): 39\n\nExport Date: 15 January 2013\n\nSource: Scopus\n\nCODEN: ACBEE\n\ndoi: 10.1016/j.apcatb.2004.01.016\n\nLanguage of Original Document: English\n\nCorrespondence Address: Martínez-Arias, A.; Inst. de Catalisis y Petroleoquimica, CSIC, Campus Cantoblanco, 28049 Madrid, Spain; email: amartinez@icp.csic.es\n\nReferences: Peral, J.L., Ollis, D., (1992) J. Catal., 136, p. 554; \nHoffman, M.R., Martin, S.T., Choi, W., Bahnemann, D.W., (1995) Chem. Rev., 95, p. 69; \nLinsebigler, A.L., Lu, G., Yates, J.T., (1995) Chem. Rev., 95, p. 735; \nAlberici, R.M., Jardim, W.F., (1995) Appl. Catal. B, 14, p. 55; \nAnpo, M., Takeuchi, M., (2003) J. Catal., 216, p. 505; \nFuerte, A., Herń{a}ndez-Alonso, M.D., Maira, A.J., Martínez-Arias, A., Ferń{a}ndez-García, M., Conesa, J.C., Soria, J., Munuera, G., (2002) J. Catal., 212, p. 1; \nAmeen, M.M., Raupp, G.B., (1999) J. Catal., 184, p. 112; \nFuerte, A., Herń{a}ndez-Alonso, M.D., Maira, A.J., Martínez-Arias, A., Ferń{a}ndez-García, M., Conesa, J.C., Soria, J., (2001) Chem. Commun., p. 2178; \nMaira, A.J., Yeung, K.L., Soria, J., Coronado, J.M., Belver, C., Lee, C.Y., Augugliaro, V., (2001) Appl. Catal. B, 29, p. 327; \nMorimoto, T., Tomonaga, H., Mitani, A., (1999) Thin Solids Films, 351, p. 61; \nLi, R., Yabe, S., Yamashita, M., Momose, S., Yoshida, S., Yin, S., Sato, T., (2002) Solid State Ion., 151, p. 235; \nBamwenda, G.R., Sayama, K., Arakawa, H., (2000) J. Mol. Catal. a, 161, p. 105; \nBamwenda, G.R., Uesigi, T., Abe, Y., Sayama, K., Arakawa, H., (2001) Appl. Catal. a, 205, p. 117; \nChung, K.H., Park, D.C., (1996) Catal. Today, 30, p. 157; \nLin, J., Yu, J.C., (1998) J. Photochem. Photobiol. a, 116, p. 63; \nCoronado, J.M., Maira, A.J., Martínez-Arias, A., Conesa, J.C., Soria, J., (2002) J. Photochem. Photobiol. a, 150, p. 213; \nMiyauchi, M., Nakajima, A., Watanabe, T., Hashimoto, K., (2002) Chem. Mater., 14, p. 2812; \nHarrison, R.M., (1995) Volatile Organic Compounds in the Atmosphere, , The Royal Society of Chemistry, Cambridge; \nRiegel, G., Bolton, J.R., (1995) J. Phys. Chem., 99, p. 4215; \nSoria, J., Martínez-Arias, A., Conesa, J.C., (1995) J. Chem. Soc., Faraday Trans., 91, p. 1669; \nConesa, J.C., Ferń{a}ndez-García, M., Martínez-Arias, A., (2002) Catalysis by Ceria and Related Materials, p. 169. , A. Trovarelli (Ed.), Imperial College Press, London; \nMartínez-Arias, A., Ferń{a}ndez-García, M., Ballesteros, V., Salamanca, L.N., Conesa, J.C., Otero, C., Soria, J., (1999) Langmuir, 15, p. 4796; \nGrela, M.A., Coronel, M.E.J., Colussi, A.J., (1996) J. Phys. Chem., 100, p. 16940; \nZhang, F., Chan, S., Spanier, J.E., Apak, E., Jin, Q., Robinson, R.D., Herman, I.P., (2002) Appl. Phys. Lett., 80, p. 127; \nZhang, J., Ju, X., Wu, Z.Y., Liu, T., Hu, T.D., Xie, Y.N., Zhang, Z.L., (2001) Chem. Mater., 13, p. 4192; \nFinnie, K.S., Cassidy, D.J., Bartlett, J.R., Woolfrey, J.L., (2001) Langmuir, 17, p. 816; \nTanaka, K., White, J., (1982) J. Phys. Chem., 86, p. 4708; \nLi, C., Sakata, Y., Arai, T., Domen, K., Maruya, K., Onishi, T., (1989) J. Chem. Soc., Faraday Trans. 1, 85, p. 929; \nTsuhako, M., Ikeuchi, S., Matsuo, T., Motooka, I., Kobayashi, M., (1979) Bull. Chem. Soc. Jpn., 52, p. 1034; \nMartínez-Arias, A., Soria, J., Conesa, J.C., Seoane, X.L., Arcoya, A., Cataluña, R., (1995) J. Chem. Soc., Faraday Trans., 91, p. 1679; \nN̈{o}remberg, H., Briggs, G.A.D., (1997) Phys. Rev. Lett., 79, p. 4222; \nConesa, J.C., (1995) Surf. Sci., 339, p. 337; \nMartínez-Arias, A., Ferń{a}ndez-García, M., Salamanca, L.N., Valenzuela, R.X., Conesa, J.C., Soria, J., (2000) J. Phys. Chem. B, 104, p. 4038; \nCoronado, J.M., Maira, A.J., Conesa, J.C., Yeung, K.L., Augugliaro, V., Soria, J., (2001) Langmuir, 17, p. 5368; \nFigaj, M., Becker, K.D., (2001) Solid State Ion., 141, p. 507; \nHowe, R.F., Gr̈{a}tzel, M., (1987) J. Phys. Chem., 91, p. 3906; \nNakaoka, Y., Nosaka, Y., (1997) J. Photochem. Photobiol. a, 110, p. 299; \nChe, M., Tench, A.J., (1982) Adv. Catal., 31, p. 77; \nDvoranov́{a}, D., Brezov́{a}, V., Mazur, M., Malati, M.A., (2002) Appl. Catal. B, 37, p. 91; \nBrezov́{a}, V., Stasko, A., Lapcik, L., (1991) J. Photochem. Photobiol. a, 59, p. 115; \nJanzen, E.G., Sankuratry, N., Kotake, Y., (1996) J. Magn. Reson., 111, p. 254; \nGonź{a}lez, M.A., Howell, S.G., Sikdar, S.K., (1999) J. Catal., 183, p. 159; \nLi, C., Xin, Q., Guo, X., (1992) Catal. Lett., 12, p. 297; \nYeung, K.L., Maira, A.J., Stolz, J., Hung, E., Ho, N.K., Wei, A.C., Soria, J., Yue, P.L., (2002) J. Phys. Chem. B, 106, p. 4608; \nTaborda, A.V., Brusa, M.A., Grela, M.A., (2001) Appl. Catal. a, 208, p. 419; \nFuerte, A., Herń{a}ndez-Alonso, M.D., Iglesias-Juez, A., Martínez-Arias, A., Conesa, J.C., Soria, J., Ferń{a}ndez-García, M., (2003) Phys. Chem. Chem. Phys., 5, p. 2913; \nHaber, J., Tokarz, R., Witko, M., (1994) New Developments in Selective Oxidation, p. 739. , V. Cortés Corbeŕ{a}n, S. Vic Belĺ{o}n (Eds.), Elsevier, Amsterdam},\n author = {Herń{a}ndez-Alonso, M D and Hungría, A B and Martínez-Arias, A and Ferń{a}ndez-García, M and Coronado, J M and Conesa, J C and Soria, J},\n issn = {09263373 (ISSN) },\n journal = {Applied Catalysis B: Environmental},\n keywords = {Adsorption,Catalyst activity,CeO2,Cerium compounds,Charge carriers,DMPO spin-trap,EPR,Electron spin resonance spectroscopy,Electron trapping,Lethrinidae,Lighting,Microemulsions,Nanoparticles,Nanostructured materials,Phosphorus poisoning,Photoadsorption,Photocatalysis,Photooxidation,Photooxidation rates,Radicals,Superoxide,Toluene,Ultraviolet radiation,VOCs removal},\n number = {3},\n pages = {167--175},\n title = {{EPR study of the photoassisted formation of radicals on CeO2 nanoparticles employed for toluene photooxidation}},\n url = {https://www.scopus.com/inward/record.url?eid=2-s2.0-2342535623\\&partnerID=40\\&md5=160273b520d2dfa21c696aa2bd0ca1c7},\n volume = {50},\n year = {2004}\n}</pre>\n</div>\n\n\n<div class=\"well well-small bibbase\" id=\"abstract_Hernandez_Alonso2004\"\n style=\"display:none\">\n Photoactivated processes occurring upon UV illumination of CeO2 nanoparticles prepared from reverse microemulsions have been studied by means of EPR spectroscopy. Different experimental approaches have been employed aiming to determine the capability of the samples for the trapping of photogenerated charge carriers either in the absence or in the presence of external scavengers or spin-trapping agents (O2 or DMPO molecules). These results are discussed in connection with the photocatalytic activity obtained over the samples for toluene oxidation. Under the employed experimental conditions, hydroxyl and superoxide radicals are detected as main species resulting from hole and electron trapping, respectively, at the surface of the samples. The photocatalytic activity of the samples can be related to the efficiency in the charge separation processes, in accordance with EPR results of oxygen photoadsorption. However, the nature of the active species is uncertain since no correlation is found between the activities for generation of hydroxyl radicals, based on DMPO trapping EPR experiments, and the photooxidation rates. This suggests the direct involvement of holes or other type of hole-derived entities as active species. © 2004 Elsevier B.V. All rights reserved.\n</div>\n\n\n</div>\n","downloads":0,"keyword":["Adsorption","Catalyst activity","CeO2","Cerium compounds","Charge carriers","DMPO spin-trap","EPR","Electron spin resonance spectroscopy","Electron trapping","Lethrinidae","Lighting","Microemulsions","Nanoparticles","Nanostructured materials","Phosphorus poisoning","Photoadsorption","Photocatalysis","Photooxidation","Photooxidation rates","Radicals","Superoxide","Toluene","Ultraviolet radiation","VOCs removal"],"abstract":"Photoactivated processes occurring upon UV illumination of CeO2 nanoparticles prepared from reverse microemulsions have been studied by means of EPR spectroscopy. Different experimental approaches have been employed aiming to determine the capability of the samples for the trapping of photogenerated charge carriers either in the absence or in the presence of external scavengers or spin-trapping agents (O2 or DMPO molecules). These results are discussed in connection with the photocatalytic activity obtained over the samples for toluene oxidation. Under the employed experimental conditions, hydroxyl and superoxide radicals are detected as main species resulting from hole and electron trapping, respectively, at the surface of the samples. The photocatalytic activity of the samples can be related to the efficiency in the charge separation processes, in accordance with EPR results of oxygen photoadsorption. However, the nature of the active species is uncertain since no correlation is found between the activities for generation of hydroxyl radicals, based on DMPO trapping EPR experiments, and the photooxidation rates. This suggests the direct involvement of holes or other type of hole-derived entities as active species. © 2004 Elsevier B.V. All rights reserved.","address":"Inst. de Catalisis y Petroleoquimica, CSIC, Campus Cantoblanco, 28049 Madrid, Spain","annote":"Cited By (since 1996): 39 Export Date: 15 January 2013 Source: Scopus CODEN: ACBEE doi: 10.1016/j.apcatb.2004.01.016 Language of Original Document: English Correspondence Address: Martínez-Arias, A.; Inst. de Catalisis y Petroleoquimica, CSIC, Campus Cantoblanco, 28049 Madrid, Spain; email: amartinez@icp.csic.es References: Peral, J.L., Ollis, D., (1992) J. Catal., 136, p. 554; Hoffman, M.R., Martin, S.T., Choi, W., Bahnemann, D.W., (1995) Chem. Rev., 95, p. 69; Linsebigler, A.L., Lu, G., Yates, J.T., (1995) Chem. Rev., 95, p. 735; Alberici, R.M., Jardim, W.F., (1995) Appl. Catal. B, 14, p. 55; Anpo, M., Takeuchi, M., (2003) J. Catal., 216, p. 505; Fuerte, A., Herńandez-Alonso, M.D., Maira, A.J., Martínez-Arias, A., Ferńandez-García, M., Conesa, J.C., Soria, J., Munuera, G., (2002) J. Catal., 212, p. 1; Ameen, M.M., Raupp, G.B., (1999) J. Catal., 184, p. 112; Fuerte, A., Herńandez-Alonso, M.D., Maira, A.J., Martínez-Arias, A., Ferńandez-García, M., Conesa, J.C., Soria, J., (2001) Chem. Commun., p. 2178; Maira, A.J., Yeung, K.L., Soria, J., Coronado, J.M., Belver, C., Lee, C.Y., Augugliaro, V., (2001) Appl. Catal. B, 29, p. 327; Morimoto, T., Tomonaga, H., Mitani, A., (1999) Thin Solids Films, 351, p. 61; Li, R., Yabe, S., Yamashita, M., Momose, S., Yoshida, S., Yin, S., Sato, T., (2002) Solid State Ion., 151, p. 235; Bamwenda, G.R., Sayama, K., Arakawa, H., (2000) J. Mol. Catal. a, 161, p. 105; Bamwenda, G.R., Uesigi, T., Abe, Y., Sayama, K., Arakawa, H., (2001) Appl. Catal. a, 205, p. 117; Chung, K.H., Park, D.C., (1996) Catal. Today, 30, p. 157; Lin, J., Yu, J.C., (1998) J. Photochem. Photobiol. a, 116, p. 63; Coronado, J.M., Maira, A.J., Martínez-Arias, A., Conesa, J.C., Soria, J., (2002) J. Photochem. Photobiol. a, 150, p. 213; Miyauchi, M., Nakajima, A., Watanabe, T., Hashimoto, K., (2002) Chem. Mater., 14, p. 2812; Harrison, R.M., (1995) Volatile Organic Compounds in the Atmosphere, , The Royal Society of Chemistry, Cambridge; Riegel, G., Bolton, J.R., (1995) J. Phys. Chem., 99, p. 4215; Soria, J., Martínez-Arias, A., Conesa, J.C., (1995) J. Chem. Soc., Faraday Trans., 91, p. 1669; Conesa, J.C., Ferńandez-García, M., Martínez-Arias, A., (2002) Catalysis by Ceria and Related Materials, p. 169. , A. Trovarelli (Ed.), Imperial College Press, London; Martínez-Arias, A., Ferńandez-García, M., Ballesteros, V., Salamanca, L.N., Conesa, J.C., Otero, C., Soria, J., (1999) Langmuir, 15, p. 4796; Grela, M.A., Coronel, M.E.J., Colussi, A.J., (1996) J. Phys. Chem., 100, p. 16940; Zhang, F., Chan, S., Spanier, J.E., Apak, E., Jin, Q., Robinson, R.D., Herman, I.P., (2002) Appl. Phys. Lett., 80, p. 127; Zhang, J., Ju, X., Wu, Z.Y., Liu, T., Hu, T.D., Xie, Y.N., Zhang, Z.L., (2001) Chem. Mater., 13, p. 4192; Finnie, K.S., Cassidy, D.J., Bartlett, J.R., Woolfrey, J.L., (2001) Langmuir, 17, p. 816; Tanaka, K., White, J., (1982) J. Phys. Chem., 86, p. 4708; Li, C., Sakata, Y., Arai, T., Domen, K., Maruya, K., Onishi, T., (1989) J. Chem. Soc., Faraday Trans. 1, 85, p. 929; Tsuhako, M., Ikeuchi, S., Matsuo, T., Motooka, I., Kobayashi, M., (1979) Bull. Chem. Soc. Jpn., 52, p. 1034; Martínez-Arias, A., Soria, J., Conesa, J.C., Seoane, X.L., Arcoya, A., Cataluña, R., (1995) J. Chem. Soc., Faraday Trans., 91, p. 1679; N̈oremberg, H., Briggs, G.A.D., (1997) Phys. Rev. Lett., 79, p. 4222; Conesa, J.C., (1995) Surf. Sci., 339, p. 337; Martínez-Arias, A., Ferńandez-García, M., Salamanca, L.N., Valenzuela, R.X., Conesa, J.C., Soria, J., (2000) J. Phys. Chem. B, 104, p. 4038; Coronado, J.M., Maira, A.J., Conesa, J.C., Yeung, K.L., Augugliaro, V., Soria, J., (2001) Langmuir, 17, p. 5368; Figaj, M., Becker, K.D., (2001) Solid State Ion., 141, p. 507; Howe, R.F., Gr̈atzel, M., (1987) J. Phys. Chem., 91, p. 3906; Nakaoka, Y., Nosaka, Y., (1997) J. Photochem. Photobiol. a, 110, p. 299; Che, M., Tench, A.J., (1982) Adv. Catal., 31, p. 77; Dvoranov́a, D., Brezov́a, V., Mazur, M., Malati, M.A., (2002) Appl. Catal. B, 37, p. 91; Brezov́a, V., Stasko, A., Lapcik, L., (1991) J. Photochem. Photobiol. a, 59, p. 115; Janzen, E.G., Sankuratry, N., Kotake, Y., (1996) J. Magn. Reson., 111, p. 254; Gonźalez, M.A., Howell, S.G., Sikdar, S.K., (1999) J. Catal., 183, p. 159; Li, C., Xin, Q., Guo, X., (1992) Catal. Lett., 12, p. 297; Yeung, K.L., Maira, A.J., Stolz, J., Hung, E., Ho, N.K., Wei, A.C., Soria, J., Yue, P.L., (2002) J. Phys. Chem. B, 106, p. 4608; Taborda, A.V., Brusa, M.A., Grela, M.A., (2001) Appl. Catal. a, 208, p. 419; Fuerte, A., Herńandez-Alonso, M.D., Iglesias-Juez, A., Martínez-Arias, A., Conesa, J.C., Soria, J., Ferńandez-García, M., (2003) Phys. Chem. Chem. Phys., 5, p. 2913; Haber, J., Tokarz, R., Witko, M., (1994) New Developments in Selective Oxidation, p. 739. , V. Cortés Corbeŕan, S. Vic Belĺon (Eds.), Elsevier, Amsterdam","author":["Herńandez-Alonso","D, M","Hungría","B, A","Martínez-Arias, A","Ferńandez-García, M","Coronado","M, J","Conesa","C, J","Soria, J"],"author_short":["Herńandez-Alonso","D, M.","Hungría","B, A.","Martínez-Arias, A.","Ferńandez-García, M.","Coronado","M, J.","Conesa","C, J.","Soria, J."],"bibtex":"@article{ Hernandez-Alonso2004,\n abstract = {Photoactivated processes occurring upon UV illumination of CeO2 nanoparticles prepared from reverse microemulsions have been studied by means of EPR spectroscopy. Different experimental approaches have been employed aiming to determine the capability of the samples for the trapping of photogenerated charge carriers either in the absence or in the presence of external scavengers or spin-trapping agents (O2 or DMPO molecules). These results are discussed in connection with the photocatalytic activity obtained over the samples for toluene oxidation. Under the employed experimental conditions, hydroxyl and superoxide radicals are detected as main species resulting from hole and electron trapping, respectively, at the surface of the samples. The photocatalytic activity of the samples can be related to the efficiency in the charge separation processes, in accordance with EPR results of oxygen photoadsorption. However, the nature of the active species is uncertain since no correlation is found between the activities for generation of hydroxyl radicals, based on DMPO trapping EPR experiments, and the photooxidation rates. This suggests the direct involvement of holes or other type of hole-derived entities as active species. © 2004 Elsevier B.V. All rights reserved.},\n address = {Inst. de Catalisis y Petroleoquimica, CSIC, Campus Cantoblanco, 28049 Madrid, Spain},\n annote = {Cited By (since 1996): 39\n\nExport Date: 15 January 2013\n\nSource: Scopus\n\nCODEN: ACBEE\n\ndoi: 10.1016/j.apcatb.2004.01.016\n\nLanguage of Original Document: English\n\nCorrespondence Address: Martínez-Arias, A.; Inst. de Catalisis y Petroleoquimica, CSIC, Campus Cantoblanco, 28049 Madrid, Spain; email: amartinez@icp.csic.es\n\nReferences: Peral, J.L., Ollis, D., (1992) J. Catal., 136, p. 554; \nHoffman, M.R., Martin, S.T., Choi, W., Bahnemann, D.W., (1995) Chem. Rev., 95, p. 69; \nLinsebigler, A.L., Lu, G., Yates, J.T., (1995) Chem. Rev., 95, p. 735; \nAlberici, R.M., Jardim, W.F., (1995) Appl. Catal. B, 14, p. 55; \nAnpo, M., Takeuchi, M., (2003) J. Catal., 216, p. 505; \nFuerte, A., Herń{a}ndez-Alonso, M.D., Maira, A.J., Martínez-Arias, A., Ferń{a}ndez-García, M., Conesa, J.C., Soria, J., Munuera, G., (2002) J. Catal., 212, p. 1; \nAmeen, M.M., Raupp, G.B., (1999) J. Catal., 184, p. 112; \nFuerte, A., Herń{a}ndez-Alonso, M.D., Maira, A.J., Martínez-Arias, A., Ferń{a}ndez-García, M., Conesa, J.C., Soria, J., (2001) Chem. Commun., p. 2178; \nMaira, A.J., Yeung, K.L., Soria, J., Coronado, J.M., Belver, C., Lee, C.Y., Augugliaro, V., (2001) Appl. Catal. B, 29, p. 327; \nMorimoto, T., Tomonaga, H., Mitani, A., (1999) Thin Solids Films, 351, p. 61; \nLi, R., Yabe, S., Yamashita, M., Momose, S., Yoshida, S., Yin, S., Sato, T., (2002) Solid State Ion., 151, p. 235; \nBamwenda, G.R., Sayama, K., Arakawa, H., (2000) J. Mol. Catal. a, 161, p. 105; \nBamwenda, G.R., Uesigi, T., Abe, Y., Sayama, K., Arakawa, H., (2001) Appl. Catal. a, 205, p. 117; \nChung, K.H., Park, D.C., (1996) Catal. Today, 30, p. 157; \nLin, J., Yu, J.C., (1998) J. Photochem. Photobiol. a, 116, p. 63; \nCoronado, J.M., Maira, A.J., Martínez-Arias, A., Conesa, J.C., Soria, J., (2002) J. Photochem. Photobiol. a, 150, p. 213; \nMiyauchi, M., Nakajima, A., Watanabe, T., Hashimoto, K., (2002) Chem. Mater., 14, p. 2812; \nHarrison, R.M., (1995) Volatile Organic Compounds in the Atmosphere, , The Royal Society of Chemistry, Cambridge; \nRiegel, G., Bolton, J.R., (1995) J. Phys. Chem., 99, p. 4215; \nSoria, J., Martínez-Arias, A., Conesa, J.C., (1995) J. Chem. Soc., Faraday Trans., 91, p. 1669; \nConesa, J.C., Ferń{a}ndez-García, M., Martínez-Arias, A., (2002) Catalysis by Ceria and Related Materials, p. 169. , A. Trovarelli (Ed.), Imperial College Press, London; \nMartínez-Arias, A., Ferń{a}ndez-García, M., Ballesteros, V., Salamanca, L.N., Conesa, J.C., Otero, C., Soria, J., (1999) Langmuir, 15, p. 4796; \nGrela, M.A., Coronel, M.E.J., Colussi, A.J., (1996) J. Phys. Chem., 100, p. 16940; \nZhang, F., Chan, S., Spanier, J.E., Apak, E., Jin, Q., Robinson, R.D., Herman, I.P., (2002) Appl. Phys. Lett., 80, p. 127; \nZhang, J., Ju, X., Wu, Z.Y., Liu, T., Hu, T.D., Xie, Y.N., Zhang, Z.L., (2001) Chem. Mater., 13, p. 4192; \nFinnie, K.S., Cassidy, D.J., Bartlett, J.R., Woolfrey, J.L., (2001) Langmuir, 17, p. 816; \nTanaka, K., White, J., (1982) J. Phys. Chem., 86, p. 4708; \nLi, C., Sakata, Y., Arai, T., Domen, K., Maruya, K., Onishi, T., (1989) J. Chem. Soc., Faraday Trans. 1, 85, p. 929; \nTsuhako, M., Ikeuchi, S., Matsuo, T., Motooka, I., Kobayashi, M., (1979) Bull. Chem. Soc. Jpn., 52, p. 1034; \nMartínez-Arias, A., Soria, J., Conesa, J.C., Seoane, X.L., Arcoya, A., Cataluña, R., (1995) J. Chem. Soc., Faraday Trans., 91, p. 1679; \nN̈{o}remberg, H., Briggs, G.A.D., (1997) Phys. Rev. Lett., 79, p. 4222; \nConesa, J.C., (1995) Surf. Sci., 339, p. 337; \nMartínez-Arias, A., Ferń{a}ndez-García, M., Salamanca, L.N., Valenzuela, R.X., Conesa, J.C., Soria, J., (2000) J. Phys. Chem. B, 104, p. 4038; \nCoronado, J.M., Maira, A.J., Conesa, J.C., Yeung, K.L., Augugliaro, V., Soria, J., (2001) Langmuir, 17, p. 5368; \nFigaj, M., Becker, K.D., (2001) Solid State Ion., 141, p. 507; \nHowe, R.F., Gr̈{a}tzel, M., (1987) J. Phys. Chem., 91, p. 3906; \nNakaoka, Y., Nosaka, Y., (1997) J. Photochem. Photobiol. a, 110, p. 299; \nChe, M., Tench, A.J., (1982) Adv. Catal., 31, p. 77; \nDvoranov́{a}, D., Brezov́{a}, V., Mazur, M., Malati, M.A., (2002) Appl. Catal. B, 37, p. 91; \nBrezov́{a}, V., Stasko, A., Lapcik, L., (1991) J. Photochem. Photobiol. a, 59, p. 115; \nJanzen, E.G., Sankuratry, N., Kotake, Y., (1996) J. Magn. Reson., 111, p. 254; \nGonź{a}lez, M.A., Howell, S.G., Sikdar, S.K., (1999) J. Catal., 183, p. 159; \nLi, C., Xin, Q., Guo, X., (1992) Catal. Lett., 12, p. 297; \nYeung, K.L., Maira, A.J., Stolz, J., Hung, E., Ho, N.K., Wei, A.C., Soria, J., Yue, P.L., (2002) J. Phys. Chem. B, 106, p. 4608; \nTaborda, A.V., Brusa, M.A., Grela, M.A., (2001) Appl. Catal. a, 208, p. 419; \nFuerte, A., Herń{a}ndez-Alonso, M.D., Iglesias-Juez, A., Martínez-Arias, A., Conesa, J.C., Soria, J., Ferń{a}ndez-García, M., (2003) Phys. Chem. Chem. Phys., 5, p. 2913; \nHaber, J., Tokarz, R., Witko, M., (1994) New Developments in Selective Oxidation, p. 739. , V. Cortés Corbeŕ{a}n, S. Vic Belĺ{o}n (Eds.), Elsevier, Amsterdam},\n author = {Herń{a}ndez-Alonso, M D and Hungría, A B and Martínez-Arias, A and Ferń{a}ndez-García, M and Coronado, J M and Conesa, J C and Soria, J},\n issn = {09263373 (ISSN) },\n journal = {Applied Catalysis B: Environmental},\n keywords = {Adsorption,Catalyst activity,CeO2,Cerium compounds,Charge carriers,DMPO spin-trap,EPR,Electron spin resonance spectroscopy,Electron trapping,Lethrinidae,Lighting,Microemulsions,Nanoparticles,Nanostructured materials,Phosphorus poisoning,Photoadsorption,Photocatalysis,Photooxidation,Photooxidation rates,Radicals,Superoxide,Toluene,Ultraviolet radiation,VOCs removal},\n number = {3},\n pages = {167--175},\n title = {{EPR study of the photoassisted formation of radicals on CeO2 nanoparticles employed for toluene photooxidation}},\n url = {https://www.scopus.com/inward/record.url?eid=2-s2.0-2342535623\\&partnerID=40\\&md5=160273b520d2dfa21c696aa2bd0ca1c7},\n volume = {50},\n year = {2004}\n}","bibtype":"article","id":"Hernandez-Alonso2004","issn":"09263373 (ISSN)","journal":"Applied Catalysis B: Environmental","key":"Hernandez-Alonso2004","keywords":"Adsorption,Catalyst activity,CeO2,Cerium compounds,Charge carriers,DMPO spin-trap,EPR,Electron spin resonance spectroscopy,Electron trapping,Lethrinidae,Lighting,Microemulsions,Nanoparticles,Nanostructured materials,Phosphorus poisoning,Photoadsorption,Photocatalysis,Photooxidation,Photooxidation rates,Radicals,Superoxide,Toluene,Ultraviolet radiation,VOCs removal","number":"3","pages":"167--175","title":"EPR study of the photoassisted formation of radicals on CeO2 nanoparticles employed for toluene photooxidation","type":"article","url":"https://www.scopus.com/inward/record.url?eid=2-s2.0-2342535623\\&partnerID=40\\&md5=160273b520d2dfa21c696aa2bd0ca1c7","volume":"50","year":"2004","role":"author","urls":{"Paper":"https://www.scopus.com/inward/record.url?eid=2-s2.0-2342535623\\&partnerID=40\\&md5=160273b520d2dfa21c696aa2bd0ca1c7"},"bibbaseid":"-d--b-martnezarias-fernandezgarca--m--c-soria-eprstudyofthephotoassistedformationofradicalsonceo2nanoparticlesemployedfortoluenephotooxidation-2004"},"bibtype":"article","biburl":"http://www2.uca.es/dept/cmat_qinor/nanomat/People/Hungria.bib","downloads":0,"search_terms":["epr","study","photoassisted","formation","radicals","ceo2","nanoparticles","employed","toluene","photooxidation","herńandez-alonso","d","hungría","b","martínez-arias","ferńandez-garcía","coronado","m","conesa","c","soria"],"title":"EPR study of the photoassisted formation of radicals on CeO2 nanoparticles employed for toluene photooxidation","title_words":["epr","study","photoassisted","formation","radicals","ceo2","nanoparticles","employed","toluene","photooxidation"],"year":2004,"dataSources":["HXzkPiKpD4u9iJ9ci"]}