Heterogenous Catalysis Mediated by Plasmon Heating

Abstract

We introduce a new method for performing and miniaturizing many types of heterogeneous catalysis involving nanoparticles. The method makes use of the plasmon resonance present in nanoscale metal catalysts to provide the necessary heat of reaction when illuminated with a low-power laser. We demonstrate our approach by reforming a flowing, liquid mixture of ethanol and water over gold nanoparticle catalysts in a microfluidic channel. Plasmon heating of the nanoparticles provides not only the heat of reaction but the means to generate both water and ethanol vapor locally over the catalysts, which in turn allows the chip and the fluid lines to remain at room temperature. The measured products of the reaction, CO 2 , CO, and H 2 , are consistent with catalytic steam reforming of ethanol. The approach, which we refer to as plasmon-assisted catalysis, is general and can be used with a variety of endothermic catalytic processes involving nanoparticles.

Plasmonic photocatalytic reactions enhanced by hot electrons in a one-dimensional quantum well

“…A plasmon [1][2][3][4][5][6][7] is the quantized collective motion of free electrons induced in metals under external light illumination. Plasmons can generate giant electromagnetic field and high-density free electrons localized in a small, limited space.…”

“…[8][9][10][11][12][13][14][15][16][17] Recently, quantum hot charge carriers (QHC), or hot electrons, generated by the decay of a plasmon were demonstrated to greatly enhance photocatalytic reactions. [2][3][4][5]18 In this study, the plasmonic enhancement of the chemical oxidization of ammonium ions in water is presented.…”

Controlled synthesis of gold nanosnakes assisted by poly(vinyl pyrrolidone)–sodium dodecyl sulphate aggregations

“…Tremendous attention has been focused on the synthesis of nanocrystals because of their potential applications in areas such as catalysis [1,2], biosensor [3] and surface-enhanced Raman scattering [4]. One of the recent promising works in this field is the controlled synthesis of branched nanostructures, such as nanotadpoles [5], nanokites [6], nanoleaves [7] and highly branched nanoplates [8].…”

Behavior of microbubbles on spatially controlled golden nanoparticles

“…In fact, the plasmonic bubble generation under CW illumination had received considerable attention until recently [17] . In 2009, Adleman et al [18] were the first scholars who focused a CW laser on a flowing ethanol-water mixture over gold nanoparticles and provided the necessary heat of heterogeneous catalysis. In 2012, Hühn et al [19] studied bubble generation around nanoparticles under CW heating and to hypothesize superheating.…”

“…Because plasmonic resonance is a rapid process that happens on a picosecond time scale [18] , we focus the rapid expansion process of plasmonic bubbles within 0.025 s. Notice that the velocity of the plasmonic bubbles also depends on the inter-nanopillars. By simulating the radius curve, the velocity of the bubbles can be derived by differentiating the simulated curve, as shown in Fig.…”