Highly selective oxidation of methane to methanol at ambient conditions by titanium dioxide-supported iron species

Abstract

Methane activation under moderate conditions and with good selectivity for value-added chemicals still remains a huge challenge. Here, we present a highly selective catalyst for the transformation of methane to methanol composed of highly dispersed iron species on titanium dioxide. The catalyst operates under moderate light irradiation (close to one Sun) and at ambient conditions. The optimized sample shows a 15% conversion rate for methane with an alcohol selectivity of over 97% (methanol selectivity over 90%) and a yield of 18 moles of alcohol per mole of iron active site in just 3 hours. X-ray photoelectron spectroscopy measurements with and without xenon lamp irradiation, light-intensity-modulated spectroscopies, photoelectrochemical measurements, X-ray absorption near-edge structure and extended X-ray absorption fine structure spectra, as well as isotopic analysis confirm the function of the major iron-containing species—namely, FeOOH and Fe2O3, which enhance charge transfer and separation, decrease the overpotential of the reduction reaction and improve selectivity towards methanol over carbon dioxide production.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.

from$8.99

All prices are NET prices.

Fig. 1: Photocatalytic methane conversion under different conditions.
Fig. 2: Stability of photocatalysts and carbon source identification during CH4 transformation.
Fig. 3: Physical observation of the 0.33 metalwt.% FeOx/TiO2 sample.
Fig. 4: Chemical and physical characterization of the TiO2-based photocatalysts.

Data availability

The data that support the plots within this paper and other findings of this study are available from the corresponding authors upon reasonable request.

References

  1. 1.

    McFarland, E. Unconventional chemistry for unconventional natural gas. Science 338, 341–342 (2012).

    Article  Google Scholar 

  2. 2.

    Abbas, H. F. & Wan Daud, W. M. A. Hydrogen production by methane decomposition: a review. Int. J. Hydrogen Energy 35, 1160–1190 (2010).

    CAS  Article  Google Scholar 

  3. 3.

    Ravi, M., Ranocchiari, M. & van Bokhoven, J. A. The direct catalytic oxidation of methane to methanol—a critical assessment. Angew. Chem. Int. Ed. 56, 16464–16483 (2017).

    CAS  Article  Google Scholar 

  4. 4.

    Liu, H. et al. A review of anode catalysis in the direct methanol fuel cell. J. Power Sources 155, 95–110 (2006).

    CAS  Article  Google Scholar 

  5. 5.

    Periana, R. A. et al. A mercury-catalyzed, high-yield system for the oxidation of methane to methanol. Science 259, 340–343 (1993).

    CAS  Article  Google Scholar 

  6. 6.

    Periana, R. A. et al. Methanol derivative platinum catalysts for the high-yield oxidation of methane to a methanol derivative. Science 280, 560–564 (1998).

    CAS  Article  Google Scholar 

  7. 7.

    Palkovits, R. et al. Development of molecular and solid catalysts for the direct low-temperature oxidation of methane to methanol. ChemSusChem 3, 277–282 (2010).

    CAS  Article  Google Scholar 

  8. 8.

    Zimmermann, T., Soorholtz, M., Bilke, M. & Schüth, F. Selective methane oxidation catalyzed by platinum salts in oleum at turnover frequencies of large-scale industrial processes. J. Am. Chem. Soc. 138, 12395–12400 (2016).

    CAS  Article  Google Scholar 

  9. 9.

    Muehlhofer, M., Strassner, T. & Herrmann, W. A. New catalyst systems for the catalytic conversion of methane into methanol. Angew. Chem. Int. Ed. 41, 1745–1747 (2002).

    CAS  Article  Google Scholar 

  10. 10.

    Sushkevich, V. L., Palagin, D., Ranocchiari, M. & van Bokhoven, J. A. Selective anaerobic oxidation of methane enables direct synthesis of methanol. Science 356, 523–527 (2017).

    CAS  Article  Google Scholar 

  11. 11.

    Huang, W. et al. Low-temperature transformation of methane to methanol on Pd1O4 single sites anchored on the internal surface of microporous silicate. Angew. Chem. Int. Ed. 55, 13441–13445 (2016).

    CAS  Article  Google Scholar 

  12. 12.

    Hammond, C. et al. Aqueous-phase methane oxidation over Fe-MFI zeolites; promotion through isomorphous framework substitution. ACS Catal. 3, 1835–1844 (2013).

    CAS  Article  Google Scholar 

  13. 13.

    Hammond, C. et al. Direct catalytic conversion of methane to methanol in an aqueous medium by using copper-promoted Fe-ZSM-5. Angew. Chem. Int. Ed. 51, 5129–5133 (2012).

    CAS  Article  Google Scholar 

  14. 14.

    Sobolev, V. I., Dubkov, K. A., Panna, O. V. & Panov, G. I. Selective oxidation of methane to methanol on a FeZSM-5 surface. Catal. Today 24, 251–252 (1995).

    CAS  Article  Google Scholar 

  15. 15.

    Hammond, C. et al. Elucidation and evolution of the active component within Cu/Fe/ZSM-5 for catalytic methane oxidation: from synthesis to catalysis. ACS Catal. 3, 689–699 (2013).

    CAS  Article  Google Scholar 

  16. 16.

    Liu, C.-C., Mou, C.-Y., Yu, S. S.-F. & Chan, S. I. Heterogeneous formulation of the tricopper complex for efficient catalytic conversion of methane into methanol at ambient temperature and pressure. Energy Environ. Sci. 9, 1361–1374 (2016).

    Article  Google Scholar 

  17. 17.

    Grundner, S. et al. Single-site trinuclear copper oxygen clusters in mordenite for selective conversion of methane to methanol. Nat. Commun. 6, 7546 (2015).

    Article  Google Scholar 

  18. 18.

    Ab Rahim, M. H. et al. Low temperature selective oxidation of methane to methanol using titania supported gold palladium copper catalysts. Catal. Sci. Technol. 6, 3410–3418 (2016).

    CAS  Article  Google Scholar 

  19. 19.

    Groothaert, M. H., Smeets, P. J., Sels, B. F., Jacobs, P. A. & Schoonheydt, R. A. Selective oxidation of methane by the bis(μ-oxo)dicopper core stabilized on ZSM-5 and mordenite zeolites. J. Am. Chem. Soc. 127, 1394–1395 (2005).

    CAS  Article  Google Scholar 

  20. 20.

    Sheppard, T., Hamill, C. D., Goguet, A., Rooney, D. W. & Thompson, J. M. A low temperature, isothermal gas-phase system for conversion of methane to methanol over Cu–ZSM-5. Chem. Commun. 50, 11053–11055 (2014).

    CAS  Article  Google Scholar 

  21. 21.

    Agarwal, N. et al. Aqueous Au–Pd colloids catalyze selective CH4 oxidation to CH3OH with O2 under mild conditions. Science 358, 223–227 (2017).

    CAS  Article  Google Scholar 

  22. 22.

    Shan, J., Li, M., Allard, L. F., Lee, S. & Flytzani-Stephanopoulos, M. Mild oxidation of methane to methanol or acetic acid on supported isolated rhodium catalysts. Nature 551, 605–608 (2017).

    CAS  Article  Google Scholar 

  23. 23.

    Moniz, S. J. A., Shevlin, S. A., Martin, D. J., Guo, Z.-X. & Tang, J. Visible-light driven heterojunction photocatalysts for water splitting—a critical review. Energy Environ. Sci. 8, 731–759 (2015).

    CAS  Article  Google Scholar 

  24. 24.

    Jiang, C., Moniz, S. J. A., Wang, A., Zhang, T. & Tang, J. Photoelectrochemical devices for solar water splitting—materials and challenges. Chem. Soc. Rev. 46, 4645–4660 (2017).

    CAS  Article  Google Scholar 

  25. 25.

    Kong, D. et al. Recent advances in visible light-driven water oxidation and reduction in suspension systems. Mater. Today https://doi.org/10.1016/j.mattod.2018.04.009 (in the press).

    CAS  Article  Google Scholar 

  26. 26.

    Wang, Y. et al. Mimicking natural photosynthesis: solar to renewable H2 fuel synthesis by Z-scheme water splitting systems. Chem. Rev. 118, 5201–5241 (2018).

    CAS  Article  Google Scholar 

  27. 27.

    Wang, Y. et al. Bandgap engineering of organic semiconductors for highly efficient photocatalytic water splitting. Adv. Energy Mater. 8, 1801084 (2018).

    Article  Google Scholar 

  28. 28.

    Jiang, C. et al. Size-controlled TiO2 nanoparticles on porous hosts for enhanced photocatalytic hydrogen production. Appl. Catal. A 521, 133–139 (2016).

    CAS  Article  Google Scholar 

  29. 29.

    Li, H., Shang, J., Ai, Z. & Zhang, L. Efficient visible light nitrogen fixation with BiOBr nanosheets of oxygen vacancies on the exposed {001} facets. J. Am. Chem. Soc. 137, 6393–6399 (2015).

    CAS  Article  Google Scholar 

  30. 30.

    Wang, S. et al. Light-switchable oxygen vacancies in ultrafine Bi5O7Br nanotubes for boosting solar-driven nitrogen fixation in pure water. Adv. Mater. 29, 1701774 (2017).

    Article  Google Scholar 

  31. 31.

    Ward, M. D., Brazdil, J. F., Mehandru, S. P. & Anderson, A. B. Methane photoactivation on copper molybdate. An experimental and theoretical study. J. Phys. Chem. 91, 6515–6521 (1987).

    CAS  Article  Google Scholar 

  32. 32.

    An, X., Li, K. & Tang, J. Cu2O/reduced graphene oxide composites for the photocatalytic conversion of CO2. ChemSusChem 7, 1086–1093 (2014).

    CAS  Article  Google Scholar 

  33. 33.

    Handoko, A. D., Li, K. & Tang, J. Recent progress in artificial photosynthesis: CO2 photoreduction to valuable chemicals in a heterogeneous system. Curr. Opin. Chem. Eng. 2, 200–206 (2013).

    Article  Google Scholar 

  34. 34.

    Murcia-López, S., Villa, K., Andreu, T. & Morante, J. R. Partial oxidation of methane to methanol using bismuth-based photocatalysts. ACS Catal. 4, 3013–3019 (2014).

    Article  Google Scholar 

  35. 35.

    Murcia-López, S. et al. Controlled photocatalytic oxidation of methane to methanol through surface modification of beta zeolites. ACS Catal. 7, 2878–2885 (2017).

    Article  Google Scholar 

  36. 36.

    Villa, K., Murcia-López, S., Andreu, T. & Morante, J. R. Mesoporous WO3 photocatalyst for the partial oxidation of methane to methanol using electron scavengers. Appl. Catal. B 163, 150–155 (2015).

    CAS  Article  Google Scholar 

  37. 37.

    Chen, X. et al. Photocatalytic oxidation of methane over silver decorated zinc oxide nanocatalysts. Nat. Commun. 7, 12273 (2016).

    CAS  Article  Google Scholar 

  38. 38.

    Božanić, D. K., Luyt, A. S., Trandafilović, L. V. & Djoković, V. Glycogen and gold nanoparticle bioconjugates: controlled plasmon resonance via glycogen-induced nanoparticle aggregation. RSC Adv. 3, 8705 (2013).

    Article  Google Scholar 

  39. 39.

    Wu, P., Huang, Y., Kang, L., Wu, M. & Wang, Y. Multisource synergistic electrocatalytic oxidation effect of strongly coupled PdM (M = Sn, Pb)/N-doped graphene nanocomposite on small organic molecules. Sci. Rep. 5, 14173 (2015).

    CAS  Article  Google Scholar 

  40. 40.

    Jian-Dong, X. et al. Improvement of adsorptive separation performance for C2H4/C2H6 mixture by CeO2 promoted CuCl/activated carbon adsorbents. Acta Phys. Chim. Sin. 31, 2158–2164 (2015).

    Google Scholar 

  41. 41.

    Yang, P. et al. Ultrafast-charging supercapacitors based on corn-like titanium nitride nanostructures. Adv. Sci. 3, 1500299 (2015).

    Article  Google Scholar 

  42. 42.

    Abazović, N. D. et al. Synthesis and characterization of rutile TiO2 nanopowders doped with iron ions. Nanoscale Res. Lett. 4, 518–525 (2009).

    Article  Google Scholar 

  43. 43.

    Vinayan, B. P. & Ramaprabhu, S. Platinum–TM (TM = Fe, Co) alloy nanoparticles dispersed nitrogen doped (reduced graphene oxide–multiwalled carbon nanotube) hybrid structure cathode electrocatalysts for high performance PEMFC applications. Nanoscale 5, 5109 (2013).

    CAS  Article  Google Scholar 

  44. 44.

    Kanakaraju, D., Kockler, J., Motti, C. A., Glass, B. D. & Oelgemöller, M. Titanium dioxide/zeolite integrated photocatalytic adsorbents for the degradation of amoxicillin. Appl. Catal. B 166-167, 45–55 (2015).

    CAS  Article  Google Scholar 

  45. 45.

    Xu, Z. et al. Sulfate functionalized Fe2O3 nanoparticles on TiO2 nanotube as efficient visible light-active photo-Fenton catalyst. Ind. Eng. Chem. Res. 54, 4593–4602 (2015).

    CAS  Article  Google Scholar 

  46. 46.

    Qiu, B., Xing, M. & Zhang, J. Stöber-like method to synthesize ultralight, porous, stretchable Fe2O3/graphene aerogels for excellent performance in photo-Fenton reaction and electrochemical capacitors. J. Mater. Chem. A 3, 12820–12827 (2015).

    CAS  Article  Google Scholar 

  47. 47.

    López-Martín, Á., Caballero, A. & Colón, G. Photochemical methane partial oxidation to methanol assisted by H2O2. J. Photochem. Photobiol. A 349, 216–223 (2017).

    Article  Google Scholar 

  48. 48.

    Chen, L. C., Yu, Z. & Hiraoka, K. Vapor phase detection of hydrogen peroxide with ambient sampling chemi/chemical ionization mass spectrometry. Anal. Methods 2, 897–900 (2010).

    CAS  Article  Google Scholar 

  49. 49.

    Grossnickle, J. A. et al. Particle and recycling control in translation, confinement, and sustainment upgrade. Phys. Plasmas 17, 032506 (2010).

    Article  Google Scholar 

  50. 50.

    Liu, J. et al. Designed synthesis of TiO2-modified iron oxides on/among carbon nanotubes as a superior lithium-ion storage material. J. Mater. Chem. A 2, 11372–11381 (2014).

    CAS  Article  Google Scholar 

  51. 51.

    McIntyre, N. S. & Zetaruk, D. G. X-ray photoelectron spectroscopic studies of iron oxides. Anal. Chem. 49, 1521–1529 (1977).

    CAS  Article  Google Scholar 

  52. 52.

    Kuzmin, A. & Chaboy, J. EXAFS and XANES analysis of oxides at the nanoscale. IUCrJ 1, 571–589 (2014).

    CAS  Article  Google Scholar 

  53. 53.

    Wang, Y. et al. Linker-controlled polymeric photocatalyst for highly efficient hydrogen evolution from water. Energy Environ. Sci. 10, 1643–1651 (2017).

    CAS  Article  Google Scholar 

  54. 54.

    Xie, J. et al. Efficient visible light-driven water oxidation and proton reduction by an ordered covalent triazine-based framework. Energy Environ. Sci. 11, 1617–1624 (2018).

    Article  Google Scholar 

  55. 55.

    Peter, L. in Photoelectrochemical Water Splitting: Materials, Processes and Architectures (eds Lewerenz, H.-J. & Peter, L.) 19–51 (The Royal Society of Chemistry, Cambridge, 2013).

  56. 56.

    Zhang, C. et al. Photoelectrochemical analysis of the dyed TiO2/electrolyte interface in long-term stability of dye-sensitized solar cells. J. Phys. Chem. C 116, 19807–19813 (2012).

    CAS  Article  Google Scholar 

  57. 57.

    Ruan, Q. et al. A nanojunction polymer photoelectrode for efficient charge transport and separation. Angew. Chem. Int. Ed. 56, 8221–8225 (2017).

    CAS  Article  Google Scholar 

  58. 58.

    Jiang, W. et al. Oxygen-doped carbon nitride aerogel: a self-supported photocatalyst for solar-to-chemical energy conversion. Appl. Catal. B 236, 428–435 (2018).

    CAS  Article  Google Scholar 

  59. 59.

    Wu, Z. et al. Characterization and activity of Pd-modified TiO2 catalysts for photocatalytic oxidation of NO in gas phase. J. Hazard. Mater. 164, 542–548 (2009).

    CAS  Article  Google Scholar 

  60. 60.

    Ohtsu, N., Masahashi, N., Mizukoshi, Y. & Wagatsuma, K. Hydrocarbon decomposition on a hydrophilic TiO2 surface by UV irradiation: spectral and quantitative analysis using in-situ XPS technique. Langmuir 25, 11586–11591 (2009).

    CAS  Article  Google Scholar 

  61. 61.

    Moniz, S. J. A., Shevlin, S. A., An, X., Guo, Z. X. & Tang, J.Fe2O3–TiO2 nanocomposites for enhanced charge separation and photocatalytic activity. Chem. Eur. J. 20, 15571–15579 (2014).

    CAS  Article  Google Scholar 

  62. 62.

    Kudo, A. & Miseki, Y. Heterogeneous photocatalyst materials for water splitting. Chem. Soc. Rev. 38, 253–278 (2009).

    CAS  Article  Google Scholar 

  63. 63.

    Liu, T., Li, X., Yuan, X., Wang, Y. & Li, F. Enhanced visible-light photocatalytic activity of a TiO2 hydrosol assisted by H2O2: surface complexation and kinetic modeling. J. Mol. Catal. A 414, 122–129 (2016).

    CAS  Article  Google Scholar 

  64. 64.

    Da Silva, A. C. et al. Improved photocatalytic activity of δ-FeOOH by using H2O2 as an electron acceptor. J. Photochem. Photobiol. A 332, 54–59 (2017).

    CAS  Article  Google Scholar 

  65. 65.

    Kumar, S. G. & Devi, L. G. Review on modified TiO2 photocatalysis under UV/visible light: selected results and related mechanisms on interfacial charge carrier transfer dynamics. J. Phys. Chem. A 115, 13211–13241 (2011).

    CAS  Article  Google Scholar 

  66. 66.

    Ravel, B. & Newville, M. ATHENA, ARTEMIS, HEPHAESTUS: data analysis for X-ray absorption spectroscopy using IFEFFIT. J. Synchrotron. Radiat. 12, 537–541 (2005).

    CAS  Article  Google Scholar 

  67. 67.

    Yu, H. S. et al. The XAFS beamline of SSRF. Nucl. Sci. Tech. 26, 050102 (2015).

    Google Scholar 

  68. 68.

    Dean, J. A. Lange’s Handbook of Chemistry 15th edn (McGraw-Hill, New York, 1999).

Download references

Acknowledgements

We are thankful for financial support from the UK EPSRC (EP/N009533/1), Royal Society Newton Advanced Fellowship grant (NA170422), Leverhulme Trust (RPG-2017-122), Natural Science Foundation of China (21725301, 91645115, 21473003, 21821004, 21573264, 21622310, 21603247 and 21703266), National Key R&D Program of China (2017YFB0602200), China Scholarship Council and First UCL-PKU Strategic Partner Funds. The ICP-AES tests were conducted at UCL Earth Sciences by B. Belgrave. We also thank X. Han from Beijing University of Technology for the contributions on STEM observation. The X-ray absorption spectroscopy experiments were carried out at the SSRF and Beijing Synchrotron Radiation Facility. We are also thankful to C. Windle at UCL for valuable discussion and thorough checks.

Author information

Affiliations

Authors

Contributions

J.X. conducted the catalysts preparation, activity tests and sample characterizations by XPS, photoluminescence and scanning electron microscopy. R.J. analysed and discussed the results of TEM, XAFS and XPS with and without xenon lamp irradiation. A.L. carried out the STEM. Y.B. and Y.Z. conducted and analysed the sample by XPS with and without xenon lamp irradiation. Q.R. collected X-ray diffraction patterns, and carried out IMPS and IMVS measurements and H2O2 reduction in a three-electrode cell. Y.D. conducted the EXAFS and XANES experiments. S.Y. and G.S. contributed to the discussion of the XAFS results and reaction mechanism. J.T. and D.M. designed the project. J.T. supervised the progress of the entire project. The manuscript was written through collective contributions from all authors. All authors approved the final version of the manuscript.

Corresponding author

Correspondence to Junwang Tang.

Ethics declarations

Competing interests

The authors declare no competing interests.

Additional information

Publisher’s note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary information

Supplementary Information

Supplementary Discussion; Supplementary Figures 1–32; Supplementary Tables 1–2; Supplementary References

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Xie, J., Jin, R., Li, A. et al. Highly selective oxidation of methane to methanol at ambient conditions by titanium dioxide-supported iron species. Nat Catal 1, 889–896 (2018). https://doi.org/10.1038/s41929-018-0170-x

Download citation

Further reading