Plasma-driven solution electrolysis

Abstract

Plasmas interacting with liquids enable the generation of a highly reactive interfacial liquid layer due to a variety of processes driven by plasma-produced electrons, ions, photons, and radicals. These processes show promise to enable selective, efficient, and green chemical transformations and new material synthesis approaches. While many differences are to be expected between conventional electrolysis and plasma–liquid interactions, plasma–liquid interactions can be viewed, to a first approximation, as replacing a metal electrode in an electrolytic cell with a gas phase plasma. For this reason, we refer to this method as plasma-driven solution electrochemistry (PDSE). In this Perspective, we address two fundamental questions that should be answered to enable researchers to make transformational advances in PDSE: How far from equilibrium can plasma-induced solution processes be driven? and What are the fundamental differences between PDSE and other more traditional electrochemical processes? Different aspects of both questions are discussed in five sub-questions for which we review the current state-of-the art and we provide a motivation and research vision.

Disproportionation of nitrogen induced by DC plasma-driven electrolysis in a nitrogen atmosphere

“…Plasma-driven electrochemistry has attracted growing attention as a method to electrify the chemical industry thereby providing novel green chemical transformation processes, including NF. 50,51 In this interesting approach, hydrogen (H 2 ) and oxygen (O 2 ) are supplied through the hydrogen evolutions reaction (HER) and oxygen evolution reaction (OER) driven by water electrolysis, while the nitrogen plasma allows excitation and dissociation of N 2 molecules and their subsequent reaction with other species in the gas discharge, in particular H 2 O molecules. As this system appears suitable for nitrogen disproportionation, the mechanisms for nitrogen oxidation and reduction need to be clearly understood in order to control the (energy-efficient) synthesis of specific compounds.…”

Influences of Plasma Plume Length on Structural, Optical and Dye Degradation Properties of Citrate-Stabilized Silver Nanoparticles Synthesized by Plasma-Assisted Reduction

“…Consecutive energy impact collisions with heavy particles cooled the electron temperature of the long jet rather than that of the short jet. Electron temperature and density also have an impact on the interaction between the plasma jet and the liquid medium [ 26 , 31 ]. In the plasma-assisted reduction of silver ions, the amount of plasma-synthesized silver nanoparticles depends on the electron density and acidity of plasma-activated medium.…”

“…The plasma jets can produce reactive oxygen and nitrogen species, charged particles, ultraviolet (UV) light, and electric fields. When the plasma jet enters the deionized water ( ), additional reactive species are generated by plasma–liquid interactions [ 25 , 26 , 27 ]. If the plasma jet is applied to an aqueous metal salt solution, plasma-generated reactive species will be affected by the reducing and scavenging activities of the plasma-activated medium [ 5 , 25 , 26 ].…”

“…When the plasma jet enters the deionized water ( ), additional reactive species are generated by plasma–liquid interactions [ 25 , 26 , 27 ]. If the plasma jet is applied to an aqueous metal salt solution, plasma-generated reactive species will be affected by the reducing and scavenging activities of the plasma-activated medium [ 5 , 25 , 26 ]. Plasma-assisted reduction of metal ions can be employed for the synthesis of various metal nanoparticles, such as Ag, Au, Cu, Fe, and alloy nanoparticles [ 5 , 20 , 28 ].…”

Plasma nitrogen fixation in the presence of a liquid interface: role of OH radicals

“…The presence of water, as one of the electrodes, helps to make the discharge more diffuse, allowing for higher gas volume treatment. 7 In addition, the so-called extended Zeldovich mechanism 8 can effectively generate NO(X 2 Π) through an additional reaction (r3):N + OH → NO + H…”