Nanocrystal-Derived Inorganic Aerogels and Their Applications

The focus of my talk will be laid on gels and aerogels manufactured from a variety of different (semiconductor and metal) colloidal nanoparticles. These “New inorganic aerogels”¹ carry an enormous potential for applications which is largely related to their extremely low density and high porosity providing access to the capacious inner surface of the interconnected nanoobjects they consist of.<br/>This will be exemplified with electrocatalytic applications of metal aerogels. An example is the recently developed facile strategy for the controllable synthesis of nanoparticle-based bimetallic Pt–Ni aerogels with high surface area and large porosity, which act as highly active and stable catalysts for the oxygen reduction reaction in polymer electrolyte fuel cell cathodes.² For gaining highest performance of these catalysts the surface chemistry³ as well as the formation mechanisms have to be studied and tuned.^4,5<br/>Further applications⁶ I will touch upon include a continuous droplet reactor for the production of millimeter sized spherical aerogels,⁷ hybrid plasmonic-aerogel materials as optical superheaters with engineered resonances,⁸ size-tunable Gold aerogels as durable and misfocus-tolerant 3D substrates for multiplex SERS detection,⁹ and the catalytic activity and selectivity in methanol steam reforming by of intermetallic compounds.¹⁰<br/><br/><br/><br/><b>References</b><br/>[1] C. Ziegler, A. Wolf, W. Liu, A.-K. Herrmann, N. Gaponik, A. Eychmüller, Angew. Chem. Int. Ed. 56, 9745 (2017).<br/>[2] S. Henning, H. Ishikawa, L. Kühn, J. Herranz, E. Müller, A. Eychmüller, T.S. Schmidt, Angew. Chem. Int. Ed. 56, 10707 (2017)<br/>[3] X. Fan, S. Zerebecki, R. Du, R. Hübner, G. Marzum, G. Jiang, Y. Hu, S. Barcikowki, S. Reichenberger, A. Eychmüller, Angew. Chem. Int. Ed. 59, 5706 (2020).<br/>[4] R. Du, J. Wang, R. Hübner, X. Fan, I. Senkowska, Y. Hu, S. Kaskel, A. Eychmüller, Nat. Comm. 11, 1590 (2020).<br/>[5] a) H. Ishikawa, S. Henning, J. Herranz, A. Eychmüller, M. Uchida, T.J. Schmidt, J. Electrochem. Soc. 165, F2 (2018), b) S. Jungblut, J.-O. Joswig, A. Eychmüller, J. Phys. Chem. C 123, 950 (2019), c) S. Jungblut, J.-O. Joswig, A. Eychmüller, Phys. Chem. Chem. Phys 21, 5723 (2019), d) R. Du, Y. Hu, R. Hübner, J.-O. Joswig, X. Fan, K. Schneider, A. Eychmüller, Science Advances 5, 4590 (2019), e) P. Chauhan, K. Hiekel, J.S. Diercks, J. Herranz, V.A. Saveleva, P. Kavlyuk, A. Eychmüller, T.S. Schmidt, ACS Mater. Au 2, 278 (2022).<br/>[6] X. Jiang, R. Du, R. Hübner, Y. Hu, A. Eychmüller, Matter 4,54 (2021).<br/>[7] L. Thoni, B. Klemmed, M. Georgi, A. Benad, S. Klosz, A. Eychmüller, RSC Adv. 10, 2277 (2020).<br/>[8] B. Klemmed, L.V. Besteiro, A. Benad, M. Georgi, Z. Wang, A.O. Govorov, A. Eychmüller, Angew. Chem. Int. Ed. 59, 1696 (2020).<br/>[9] L. Zhou, Y. Peng, N. Zhang, R. Du, R. Hübner, X. Wen, D. Li, Y. Hu, A. Eychmüller, Adv. Opt. Mater. 9, 2100352 (2021).<br/>[10] a) C. Ziegler, S. Klosz, L. Borchardt, M. Oschatz, S. Kaskel, M. Friedrich, R. Kriegel, T. Keilhauer, M. Armbrüster, Adv. Funct. Mat. 26, 1014 (2016), b) N. Köwitsch, L. Thoni, B. Klemmed, A. Benad, P. Paciok, M. Heggen, I. Köwitsch, M. Mehring, A. Eychmüller, M. Armbrüster, ACS Catalysis 11, 304 (2021), c) N. Köwitsch, L. Thoni, B. Klemmed, A. Benad, P. Paciok, M. Heggen, A. Eychmüller, M. Armbrüster, J. Phys. Chem. C 125, 9809 (2021).