Tailoring the Cathode-Electrolyte Interface with Nanoparticles for Boosting the Solid Oxide Fuel Cell Performance of Chemically Stable Proton-Conducting Electrolytes.

Solid oxide fuel cells (SOFCs) represent the most efficient devices for producing electrical power from fuels. The limit in their application is due to the high operation temperature of conventional SOFC materials. Progress is made toward lower operating temperatures using alternative oxygen-ion conducting electrolytes, but problems of stability and electronic conductivity still remain. A promising alternative is the use of chemically stable proton-conducting Y-doped BaZrO3 (BZY) electrolytes, but their practical applications are limited by the BZY's relatively low performance. Herein, it is reported that deposition by impregnation of cathode nanoparticles on BZY backbones provides a powerful strategy to improve the BZY-based SOFC performance below 600 °C, allowing an outstanding power output for this chemically stable electrolyte. Moreover, it is demonstrated that keeping the nanostructure is more important than keeping the desired chemical composition. The proposed scalable processing method can make BZY a competitive electrolyte for SOFC applications.

In Situ synthesis of self-assembled gold nanoparticles on glass or silicon substrates through reactive inkjet printing.

A facile and low cost method for the synthesis of self-assembled nanoparticles (NPs) with minimal size variation and chemical waste by using reactive inkjet printing was developed. Gold NPs with diameters as small as (8±2) nm can be made at low temperature (120 °C). The size of the resulting NPs can be readily controlled through the concentration of the gold precursor and oleylamine ink. The pure gold composition of the synthesized NPs was confirmed by energy-dispersive X-ray spectroscopy (EDXS) analysis. High-resolution SEM (HRSEM) and TEM (HRTEM), and X-ray diffraction revealed their size and face-centered cubic (fcc) crystal structure, respectively. Owing to the high density of the NP film, UV/Vis spectroscopy showed a red shift in the intrinsic plasmonic resonance peak. We envision the extension of this approach to the synthesis of other nanomaterials and the production of tailored functional nanomaterials and devices.

Multifunctional graphene/platinum/Nafion hybrids via ice templating.

We report the synthesis of multifunctional hybrids in both films and bulk form, combining electrical and ionic conductivity with porosity and catalytic activity. The hybrids are synthesized by a two-step process: (a) ice templation of an aqueous suspension comprised of Nafion, graphite oxide, and chloroplatinic acid to form a microcellular porous network and (b) mild reduction in hydrazine or monosodium citrate which leads to graphene-supported Pt nanoparticles on a Nafion scaffold.