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The energetics of La4LiAuO8

Published online by Cambridge University Press:  24 May 2011

Tori Z. Forbes
Affiliation:
Peter A. Rock Thermochemistry Laboratory and NEAT ORU (Nanomaterials in the Environment, Agriculture, and Technology Organized Research Unit), University of California, Davis, California 95616
Joshua A. Kurzman
Affiliation:
Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106
Ram Seshadri
Affiliation:
Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106; and Materials Department and Materials Research Laboratory, University of California, Santa Barbara, California 93106
Alexandra Navrotsky*
Affiliation:
Peter A. Rock Thermochemistry Laboratory and NEAT ORU (Nanomaterials in the Environment, Agriculture, and Technology Organized Research Unit), University of California, Davis, California 95616
*
b)Address all correspondence to this author. e-mail: [email protected]
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Abstract

La4LiAuO8 is a stable Au3+ oxide that was recently examined as a possible model compound for the role of Au3+ in heterogeneous catalysis. Due to the paucity of thermodynamic data, the energetics of La4LiAuO8 and its likely decomposition product, LiLaO2, were investigated. The ΔHf−ox, of La4LiAuO8 and LaLiO2 are both exothermic at −187.7 ± 5.8 and −41.4 ± 9.6 kJ/mol, respectively. From the thermodynamic data, the decomposition temperature of La4LiAuO8 was calculated as either 979 ± 95 or 1331 ± 43 °C for the formation of LiLaO2 or Li2O, respectively. Thus, LiLaO2 is the expected decomposition product.

Type
Materials Communications
Copyright
Copyright © Materials Research Society 2011

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References

REFERENCES

1.Hutchings, G.J.: Nanocrystalline gold catalysts: A reflection on catalyst discovery and the nature of active sites. Gold Bull. 42, 260 (2009).CrossRefGoogle Scholar
2.Schubert, M.M., Hackenberg, S., van Veen, A.C., Muhler, M., Plzak, V., and Jurgen Behm, R.: CO oxidation over supported gold catalysts—“inert” and “active” support materials and their role for the oxygen supply during reaction. J. Catal. 197, 113 (2001).CrossRefGoogle Scholar
3.Fierro-Gonzalez, J.C. and Gates, B.C.: Role of cationic gold in supported CO oxidation catalysts. Catal. Today 122, 201 (2007).CrossRefGoogle Scholar
4.Kurzman, J.A., Ouyang, X.Y., Bin Im, W., Li, J., Hu, J., Scott, S.L., and Seshadri, R.: La4LiAuO8 and La2BaPdO5: Comparing two highly stable d 8 square-planar oxides. Inorg. Chem. 49, 4670 (2010).CrossRefGoogle ScholarPubMed
5.Abbattista, F., Vallino, M., and Mazza, D.: Preparation and crystallographic characteristics of the new phase La2Au0.5Li0.5O4. J. Less-Common Met. 110, 391 (1985).CrossRefGoogle Scholar
6.Abbattista, F. and Vallino, M.: Remarks on the La2O3-Li2O binary system between 750 and 1000 °C. Ceram. Int. 9, 35 (1983).CrossRefGoogle Scholar
7.Deb, N., Baruah, S.D., and Dass, N.N.: Synthesis, characterization and the thermal decomposition of lithium tris(oxalato)lanthanum(III)nonahydrate and sodium tris(oxalato)lanthanum(III)octahydrate. Thermochim. Acta 326, 43 (1999).CrossRefGoogle Scholar
8.Kinnemann, A., Kieffer, R., Kaddouri, A., Poix, P., and Rehspringer, J.L.: Oxidative coupling of methane over LnLiO2, LnNaO2 and LnOx catalysts (Ln = samarium, neodymium, lanthanum X = chlorine, bromine). Promoting effect of magnesia, calcium oxide and strontium oxide. Catal. Today 6, 409 (1990).CrossRefGoogle Scholar
9.Navrotsky, A.: Progress and new directions in high temperature calorimetry revisited. Phys. Chem. Miner. 24, 222 (1997).CrossRefGoogle Scholar
10.Chase, M.W.J., Davies, C.A., Downey, J.J.R., Furrip, D.J., McDonald, R.A., and Syverud, A.N.: JANAF thermochemical tables third edition. J. Phys. Chem. Ref. Data 14 (1988).Google Scholar
11.Scherrer, P.: Bestimmung der Grösse und der inneren Struktur von Kolloidteilchen mittels Röntgenstrahlen. Nachr. Ges. Wiss. Göttingen 26, 98 (1918).Google Scholar
12.Robbie, R.A. and Hemingway, B.S.: Thermodynamic Properties of Minerals and Related Substances at 298.15 K and 1 Bar (104 Pascals) Pressure and at Higher Temperatures (U.S. Geological Bulletin, Washington, DC, 1995).Google Scholar
13.Helean, K.B. and Navrotsky, A.: Oxide melt solution calorimetry of rare earth oxides: Techniques, problems, cross-checks, successes. J. Therm. Anal. Calorim. 69, 751 (2002).CrossRefGoogle Scholar
14.Arcidiacono, S., Bieri, N.R., Poulikakos, D., and Grigoropoulos, C.P.: On the coalescence of gold nanoparticles. Int. J. Multiphase Flow 30, 979 (2004).CrossRefGoogle Scholar
15.Nanda, K.K.: Bulk cohesive energy and surface tension from the size-dependent evaporation study of nanoparticles. Appl. Phys. Lett. 87, 0219091 (2005).CrossRefGoogle Scholar
16.Ashcroft, J.S. and Schwarzmann, E.: Standard enthalpy of formation of crystalline gold(III) oxide. J. Chem. Soc., Faraday Trans 1F 68, 1360 (1972).CrossRefGoogle Scholar
17.Shi, H., Asahi, R., and Stampfl, C.: Properties of the gold oxides Au2O3 and Au2O: First-principles investigation. Phys. Rev. B 75, 20512151 (2007).CrossRefGoogle Scholar
18.Ellingham, H.J.T.: Reducibility of oxides and sulfides in metallurgical processes. J. Soc. Chem. Ind. London 63, 125 (1944).Google Scholar
19.Gaskell, D.R.: Introduction to the Thermodynamics of Materials (Taylor and Francis, New York, 2003).Google Scholar