The erosion loss of cathode is essential for the lifetime of magnetoplasmadynamic thruster(MPDT).In this work,an endurance test system for MPDT cathodes was designed and developed,and the erosion characteristics,erosi...The erosion loss of cathode is essential for the lifetime of magnetoplasmadynamic thruster(MPDT).In this work,an endurance test system for MPDT cathodes was designed and developed,and the erosion characteristics,erosion rate and erosion mechanism of the cathode were studied using the system under vacuum condition.The WCe20 hollow cathode was selected to carry out the long-term erosion of 540 h with the argon propellant supply flow rate of40 ml min^(-1),the input current of 25 A,and the central magnetic field intensity of 96 Gs.In order to predict the theoretical service life of cathode,a steady state erosion numerical model was established.The calculation results show that the total erosion rate of sputtering and evaporation is 11.58 mg h^(-1),which is slightly smaller than the test data of the average cathode corrosion rate of 12.70 mg h^(-1) in the experiment,because the experimental value includes start-up erosion rate.展开更多
Based on the great advantages of an inner hollow structure and excellent solid counterpart capacity,complex hierarchical structures have been widely used as electrodes for lithium-ion batteries.Herein,hierarchical yol...Based on the great advantages of an inner hollow structure and excellent solid counterpart capacity,complex hierarchical structures have been widely used as electrodes for lithium-ion batteries.Herein,hierarchical yolk-shell Cu_(2)O@Cu O-decorated RGO(YSRs)was designed and synthesized via a multistep approach.Octahedron-like Cu_(2)O-decorated RGO was firstly produced,in which GO was reduced slightly while cuprous oxide was synthesized.Subsequently,the controlled oxidation of Cu_(2)O@RGO led to the synthesis of special YSRs,which were composed of a solid Cu_(2)O core,spur-CuO,CuO shell,and RGO covered.As anode materials,YSRs could provide considerable capacity density.Meanwhile,the void existed between shells and solid active materials retaining the advantages of inner hollow structure.As a result,the unique architecture of the materials renders the composites with enhanced electronic and ionic diffusion kinetics,high specific capacity(~894 m Ah g^(-1),0.1 C),and an excellent rate capability.展开更多
文摘The erosion loss of cathode is essential for the lifetime of magnetoplasmadynamic thruster(MPDT).In this work,an endurance test system for MPDT cathodes was designed and developed,and the erosion characteristics,erosion rate and erosion mechanism of the cathode were studied using the system under vacuum condition.The WCe20 hollow cathode was selected to carry out the long-term erosion of 540 h with the argon propellant supply flow rate of40 ml min^(-1),the input current of 25 A,and the central magnetic field intensity of 96 Gs.In order to predict the theoretical service life of cathode,a steady state erosion numerical model was established.The calculation results show that the total erosion rate of sputtering and evaporation is 11.58 mg h^(-1),which is slightly smaller than the test data of the average cathode corrosion rate of 12.70 mg h^(-1) in the experiment,because the experimental value includes start-up erosion rate.
基金supported by National Natural Science Foundation of China(U1866203,11674263,21805221)Postdoctoral Research Foundation of China(2019M663690,2020M671606)+3 种基金National Natural Science Foundation of Shaanxi Province(2020JZ-03)Key Scientific and Technological Innovation Team of Shaanxi Province(2020TD-001)the Fundamental Research Funds for the Central Universities and the World-Class Universities(Disciplines)the Characteristic Development Guidance Funds for the Central Universities。
文摘Based on the great advantages of an inner hollow structure and excellent solid counterpart capacity,complex hierarchical structures have been widely used as electrodes for lithium-ion batteries.Herein,hierarchical yolk-shell Cu_(2)O@Cu O-decorated RGO(YSRs)was designed and synthesized via a multistep approach.Octahedron-like Cu_(2)O-decorated RGO was firstly produced,in which GO was reduced slightly while cuprous oxide was synthesized.Subsequently,the controlled oxidation of Cu_(2)O@RGO led to the synthesis of special YSRs,which were composed of a solid Cu_(2)O core,spur-CuO,CuO shell,and RGO covered.As anode materials,YSRs could provide considerable capacity density.Meanwhile,the void existed between shells and solid active materials retaining the advantages of inner hollow structure.As a result,the unique architecture of the materials renders the composites with enhanced electronic and ionic diffusion kinetics,high specific capacity(~894 m Ah g^(-1),0.1 C),and an excellent rate capability.
