Super-resolution Imaging of Surface-Plasmon Enhanced Catalysis at Nanoscale Gaps
Abstract
Optically excited surface plasmon (SP) can enhance catalytic reactions directly on plasmonic metal nanostructures or on semiconductor catalysts with supported plasmonic nanostructures. This enhanced catalysis provides a potential way to harvest solar energy directly to chemical energy, drive reactions at lower temperature, and modify catalytic selectivity. Several mechanisms may operate for the catalytic enhancement, including the thermal effect and the energetic electron effect. Differentiating these mechanisms is essential for understanding the SP-induced catalytic enhancement and exploiting it for application, but is often challenging experimentally, making new experimental methods desirable. The objective of the proposed research here is to develop novel methods to control plasmonic nanostructures and image catalytic reactions at high spatiotemporal resolution in operando, so as to quantify the kinetics and understand the mechanism of SP-enhanced catalysis on metal surfaces. To achieve this objective, the PI will combine the approaches of controlled preparation of plasmonic catalytic nanoparticles and operando and quantitative single-molecule super-resolution fluorescence imaging of catalytic reactions on individual nanostructures. The proposed research is innovative and potentially transformative because: (1) the single-molecule super-resolution imaging approach may transform the experimental landscape in studying SP-enhanced catalysis; (2) it enables the differentiation of SP-enhancement mechanisms from a spatial perspective, and can generate a direct visualization of the local enhancement effect of SP-enhanced catalysis; and (3) it will push single-molecule catalysis research into the new regime of plasmon-enhanced catalysis, beyond the previous thermal catalysis, electrocatalysis, and photo(electro)catalysis. The research objective, once achieved, should have the following broad significance and impact on AROÕs mission: (1) it will contribute fundamental knowledge about the mechanisms of SP-enhanced catalysis and advance our understanding about catalytic processes at solid-liquid interfaces, an important goal of the AROÕs Reactive Chemical Systems (RCS) program; (2) SP-enhanced catalysis may provide a direct way to utilize solar energy to drive reactions; this would be enabling for soldiers deployed in remote locations where conventional energy sources (e.g., liquid fuels or electricity) are limited; and (3) the SP-enhanced catalysis can be exploited for the development of effective catalysts for destroying chemical warfare agents or other hazardous materials, which can protect soldiers in the battlefield.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Oct 15, 2018
- Source ID
- W911NF1710590
Entities
People
- Peng Chen
Organizations
- Army Contracting Command
- Cornell University
- United States Army