Plasma Driven Solution Electrochemistry
Abstract
Plasma-induced solution chemistry can be driven by electrons, ions, photons and radicals. In thermal 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 transformations. Controlling these hot electron-driven chemical transformations in liquid requires an in-depth understanding of the underpinning processes, an understanding that is currently lacking. Gaining a fundamental insight into these processes will lead to transformational advances in new materials synthesis and in our ability to use plasmas for selective, efficient, sustainable and green chemical transformation. The goal of the proposed MURI team is to investigate foundational scientific questions addressing plasma-induced species in solutions and their role in chemical transformation. The understanding the team gains will enable the development of new plasma-driven solution electrochemistry (PDSE). We propose to exploit recent advancements in pulsed power and radio frequency plasmas to enable unprecedented controllable injection of electrons into solution on nanosecond time scales commensurate with the typical lifetime of reactive intermediates in solution. The resulting improved control of electron and ion fluxes and energies incident into the solution will enable unique and highly controlled experiments. Complemented by modeling, these investigations will enable fundamental insights into reactivity transfer from plasmas into solutions by measuring yields, energies, transport and lifetimes of plasma-produced species in solution. We will perform detailed studies of the initiating reactions, reactive intermediates and synthesis/growth processes for selected chemistries. Advanced plasma control approaches will be investigated to impact and regulate these processes and enable synthesis of nanoparticles and polymers with desired but previously uncontrollable or unattainable properties. This proposed MURI project brings together a strong team of investigators with complementary expertise, each of whom is a recognized leader in his/her respective field. The PIs reflect the required complementary expertise: plasma-liquid interactions and plasma diagnostics (Bruggeman, UMN), ultrafast laser spectroscopy for characterizing electrochemical processes (Frontiera, UMN), plasma materials synthesis (Kortshagen, UMN), plasma and in solution modeling (Kushner, University of Michigan - UM), electrochemistry and photocatalysis (Linic, UM) and electronic structure theory and reaction dynamics (Schatz, Northwestern University). The expected innovative outcomes include: (1) Fundamental understanding of the chemical processes which govern PDSE; (2) PDSE-based syntheses of new ÒenablingÓ materials; (3) Novel PDSE-based synthesis schemes to produce chemicals and materials; (4) Processing-structureproperty relationships for materials and chemicals produced by PDSE; (5) Diagnostic, theoretical and computational methods for PDSE processes. The impact of this MURI will be profound. New chemical synthesis and processing tools having temporal control commensurate with chemical conversion time scales in solution will be added to Department of Defense`s technical capabilities. In doing so, the DoD will gain unique access to an emerging paradigm of chemical processes, energy conversion strategies, polymer and nanomaterials synthesis methods.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jul 09, 2020
- Source ID
- W911NF2010105
Entities
People
- Peter J Bruggeman
Organizations
- Army Contracting Command
- United States Army
- University of Minnesota