Effect of liquid surface depression size on discharge characteristics and chemical distribution in the plasma-liquid anode system

Atmospheric pressure plasma-liquid interactions exist in a variety of applications,including wastewater treatment,wound sterilization,and disinfection.In practice,the phenomenon of liquid surface depression will inevitably appear.The applied gas will cause a depression on the liquid surface,which will undoubtedly affect the plasma generation and further affect the application performance.However,the effect of liquid surface deformation on the plasma is still unclear.In this work,numerical models are developed to reveal the mechanism of liquid surface depressions affecting plasma discharge characteristics and the consequential distribution of plasma species,and further study the influence of liquid surface depressions of different sizes generated by different helium flow rates on the plasma.Results show that the liquid surface deformation changes the initial spatial electric field,resulting in the rearrangement of electrons on the liquid surface.The charges deposited on the liquid surface further increase the degree of distortion of the electric field.Moreover,the electric field and electron distribution affected by the liquid surface depression significantly influence the generation and distribution of active species,which determines the practical effectiveness of the relevant applications.This work explores the phenomenon of liquid surface depression,which has been neglected in previous related work,and contributes to further understanding of plasma-liquid interactions,providing better theoretical guidance for related applications and technologies.

CFD simulation of effect of anode configuration on gas–liquid flow and alumina transport process in an aluminum reduction cell

Numerical simulations of gas–liquid two-phase flow and alumina transport process in an aluminum reduction cell were conducted to investigate the effects of anode configurations on the bath flow, gas volume fraction and alumina content distributions. An Euler–Euler two-fluid model was employed coupled with a species transport equation for alumina content. Three different anode configurations such as anode without a slot, anode with a longitudinal slot and anode with a transversal slot were studied in the simulation. The simulation results clearly show that the slots can reduce the bath velocity and promote the releasing of the anode gas, but can not contribute to the uniformity of the alumina content. Comparisons of the effects between the longitudinal and transversal slots indicate that the longitudinal slot is better in terms of gas–liquid flow but is disadvantageous for alumina mixing and transport process due to a decrease of anode gas under the anode bottom surface. It is demonstrated from the simulations that the mixing and transfer characteristics of alumina are controlled to great extent by the anode gas forces while the electromagnetic forces(EMFs) play the second role.

Fabrication and performance of atmospheric plasma sprayed solid oxide fuel cells with liquid antimony anodes

A solid oxide fuel cell(SOFC)with a liquid antimony anode(LAA)is a potential energy conversion technology for the use of impurity-containing fuels.Atmospheric plasma spraying(APS)technology has become a promising LAASOFC preparation method because of its economy and convenience.In this paper,button SOFCs with different cathode materials and ratios of pore former were prepared by the APS method and were operated at 750C.The effect of the cathode structure on the electrochemical performance of the LAA-SOFCs was analyzed,and an optimized spraying method for LAA-SOFCs was developed.A tubular LAA-SOFC was prepared using the APS method based on the optimized spraying method,and a peak power of 2.5 W was reached.The tubular cell was also measured at a constant current of 2 A for 20 h and was fed with a sulfur-containing fuel to demonstrate its impurity resistance and electrode stability.

Self-healing Ga-based liquid metal/alloy anodes for rechargeable batteries

With the rapid development of electronics,electric vehicles,and grid energy storage stations,higher requirements have been put forward for advanced secondary batteries.Liquid metal/alloy electrodes have been considered as a promising development direction to achieve excellent electrochemical performance in metal-ion batteries,due to their specific advantages including the excellent electrode kinetics and self-healing ability against microstructural electrode damage.For conventional liquid batteries,high temperatures are needed to keep electrode liquid and ensure the high conductivity of molten salt electrolytes,which also brings the corrosion and safety issues.Ga-based metal/alloys,which can be operated at or near room temperature,are potential candidates to circumvent the above problems.In this review,the properties and advantages of Ga-based metal/alloys are summarized.Then,Ga-based liquid metal/alloys as anodes in various metal-ion batteries are reviewed in terms of their self-healing ability,battery configurations,working mechanisms,and so on.Furthermore,some views on the future development of Ga-based electrodes in batteries are provided.

Advances on Na-K liquid alloy-based batteries

Sodium-potassium(Na^(-)K)liquid alloys attract increasing research attention,as an ideal alternative of Li metal for metal-based batteries,attributing to their high abundance,low redox potential,high capacity,and dendrite-free properties.In addition,the liquid and self-healing features of Na^(-)K alloys endow good electrode/electrolyte interfacial contact.The recent advances on the Na^(-)K liquid alloy-based batteries(NKBs)are reviewed herein.The anode designs for immobilization of the liquid alloy are introduced.The influences of the electrolyte and cathode materials on the battery performances are discussed.In addition,considering the co-existence of both K^(+)and Na^(+)in the electrolyte,the working mechanisms of the NKBs are elaborated.We also show that despite the improvement,challenges of the NKBs remain.The compatibility between Na^(-)K liquid alloy and electrolyte,as well as disputed working mechanisms,request detailed surface analyses of the liquid alloy and local element distribution evolution in the battery.This review would shed light on the fundamental understanding of Na^(-)K alloy electrochemistry and the development of dendrite-free metal-based energy storage systems with high energy density.