Noble Metal Aerogel Design for Bio-/Fuel Cell Applications

The considerable interest in energy technology has sparked a sustained research effort on fuel cells because of their high energy efficiency and outstanding environmental compatibility.[1] Aerogels derived from noble metal nanoparticles (NPs) are a new kind of materials, which not only retain the inherent characteristics of the aerogels, including high surface area, interconnected porosity in the meso and macropore size range, and nanosized primary units, but also possess high electrical conductivity and intrinsic catalytic activity.[2] These unique properties endow them with an enormous potential in applications, such as electrocatalysis.

  Our recent efforts have been focused on the design of noble metal aerogels with controllable morphologies or composition and their exploration in bio-/fuel cell applications. Via a cation-induced or a spontaneously running route, we realized the controlled growth of Pd aerogels with different porosities and surface areas and obtained aerogels composed of Pd-Ferrocene. They provided a three-dimensional matrix with high electrical conductivity and high surface area for enzyme loading, showing a promoted bioelectrocatalysis and biofuel cell application.[3,4] On the other hand, a series of highly efficient Au_xPt_y bimetallic aerogel electrocatalysts derived via a host-guest interaction-induced method exhibited high activity, low overpotential, and high CO tolerance toward the direct oxidation of methanol, ethanol and glucose.[5] Additionally, Pd_xNi_y aerogels from kinetically controlled synthesis displayed excellent performance toward the methanol oxidation.[6] Here the non-precious metal component was introduced to lower the cost of the fuel cell electrocatalyst and to increase its activity due to the bimetallic synergistic effect.

References

[1] M. Debe, Nature 2012, 486, 43–51.

[2] W. Liu, A.-K. Herrmann, N. Bigall, P. Rodriguez, D. Wen, M. Özaslan, T. Schmidt, N. Gaponik, A. Eychmüller, Acc. Chem. Res. 2014, revised.

[3] D. Wen, A.-K. Herrmann, L. Borchardt, F. Simon, W. Liu, S. Kaskel, A. Eychmüller, J. Am. Chem. Soc. 2014, 136, 2727–2730.

[4] D. Wen, W. Liu, A.-K. Herrmann, A. Eychmüller, Chem. Eur. J. 2014, 20, 4380–4385.

[5] D. Wen, W. Liu, D. Haubold, A. Eychmüller, 2014, submitted.

[6] C. Zhu , D. Wen , M. Oschatz , M. Holzschuh , W. Liu , A.-K. Herrmann , F. Simon , S. Kaskel , A. Eychmüller, small 2014, accepted, DOI: 10.1002/smll.201401432.