Quantum Cascade Laser Dual Comb Spectrometer for Quantitative in- situ Characterization of Plasma-Driven Solution Electrochemistry
Abstract
Plasma-induced solution chemistry can be driven by electrons, ions, photons and radicals. In ther-mal catalytic, electrocatalytic and plasmon-driven chemical transformations, metal surfaces play key roles. In contrast, in plasma-driven processes, electrons are produced in a gas phase plasma and injected into the interfacing liquid without the need for a solid electrode. The high-power density in plasmas enables exceptionally large yields of electrons, some having high energies up to 10 eV or more, leading to a high concentration of electrons in a near plasma-liquid interfacial region with a thickness up to a few tens of nm. These conditions enable unique chemical transfor-mations in the liquid phase. Controlling these hot electron-driven chemical transformations in liq-uid requires an in-depth understanding of the lifetime, energetics, yield, and transport of solution-phase species resulting from cascade reactions, an understanding that is currently lacking and is the topic of the MURI ?Plasma-Driven Solution Electrochemistry (PDSE)? (W911NF-20-1-0105) led by the PI. Within the framework of the MURI, in situ Raman spectroscopy, UV/VIS absorption and TEM are being developed to investigate PDSE. The proposed instrumentation purchase will enable us to extend this to IR absorption allowing us to probe a broad range of organic species in solutions which are currently not accessible. We propose in the framework of this DURIP to leverage recent advances in PDSE and frequency comb spectroscopy to implement in situ IR absorption in PDSE by the acquisition of a quantum cascade laser dual comb spectrometer complemented with a Fou-rier Transform Infrared (FTIR) spectrometer system with temperature-controlled liquid cell for calibration. The proposed capability will enable us to probe to date unexplored reaction processes in PDSE down to microsecond timescales. This will provide invaluable data for developing reac-tion mechanisms for PDSE-enabled chemical conversions of organic molecules and validation of the modeling efforts in the MURI. The anticipated gained insights will enable the development of control strategies for PDSE as a new and highly versatile approach to chemical conversion and the synthesis of chemicals, nano-particles and polymers with desired but currently uncontrollable or unattainable properties. Re-search outcomes to date show that PDSE can enable challenging chemical reactions including multi-electron reduction processes and has the potential to replace current environmentally haz-ardous chemical processes with a sustainable alternative. PDSE can address the need to develop chemical systems that can synthesize molecules on demand and at smaller scales which is com-patible with portable fuels generation with potential game-changing advances in technology and Warfighter capabilities for the Army and DoD.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Sep 01, 2023
- Source ID
- W911NF2310377
Entities
People
- Peter J Bruggeman
Organizations
- Army Contracting Command
- United States Army
- University of Minnesota