"Bridging the Size Gap: Convergence of Plasmonics and Catalysis on the Same Noble Metal Nanoparticles

May 1, 2013

Hui Wang

    Noble metal nanoparticles have been of tremendous interest because of their intriguing size- and shape-dependent plasmonic and catalytic properties. The combination of tunable plasmon resonances with superior catalytic activities on the same nanoparticle, however, has long been challenging because plasmonics and catalysis require nanoparticles in two drastically different size regimes. Tunable plasmons are a unique feature of sub-wavelength metal nanoparticles, whereas heterogeneous catalysis requires the use of sub-5 nm nanoparticles as the catalysts. My group has recently demonstrated that desired plasmonic and catalytic properties can be integrated on the same particle by controllably creating high-index facets on individual sub-wavelength metallic nanoparticles. The capabilities to both nanoengineer high-index facets and fine-tune the plasmon resonances through deliberate particle geometry control allow us to use these nanoparticles for a dual purpose: as substrates for plasmon-enhanced spectroscopies and efficient surface catalysts. Such dual functionality opens up unique opportunities for quantitative study of the intrinsic kinetics and mechanisms of surface-catalyzed reactions with unprecedented sensitivity and detail through time-resolved plasmon-enhanced spectroscopic measurements.