The effects of bentonite content on the corrosion behavior of low carbon steel in 5 mM NaHCO3+ 1 mM NaCl + 1 mM Na2SO4 solution were investigated by electrochemical measurements combined with X-ray diffraction(XRD) an...The effects of bentonite content on the corrosion behavior of low carbon steel in 5 mM NaHCO3+ 1 mM NaCl + 1 mM Na2SO4 solution were investigated by electrochemical measurements combined with X-ray diffraction(XRD) and scanning electron microscopy(SEM). In the initial immersion stage, the cathodic process of low carbon steel corrosion was dominated by the reduction of dissolved oxygen, while it transformed to the reduction of ferric corrosion products with the immersion time. The presence of bentonite colloids could suppress the cathodic reduction of oxygen due to their barrier effect on the diffusion of oxygen. However, the barrier performance of bentonite layer was gradually deteriorated due to the coagulation and separation of bentonite colloids caused by the charge neutralization of iron corrosion products dissolved from the steel substrate. More bentonite colloids could maintain the barrier effect for a long time before it was deteriorated by the accumulation of corrosion products. Conversely,it could lose the performance completely, and the corrosion behavior of low carbon steel reverted to the same as that in the blank solution.展开更多
Buffer material and metal disposal containers are the key engineering barriers in the geological disposal of high-level radioactive waste.The durability of disposal containers largely depends on the water con-tent in ...Buffer material and metal disposal containers are the key engineering barriers in the geological disposal of high-level radioactive waste.The durability of disposal containers largely depends on the water con-tent in buffer material.This work focused on investigating the corrosion evolution of NiCu low alloy steel in compacted GMZ bentonite with different water contents for 270 d by using weight loss,electrochemi-cal measurements,and various methods for analyzing corrosion products.As the water content increased from 13%to 20%,the water in the bentonite transformed from an unsaturated to a critical saturated state,and the corrosion rate of NiCu steel clearly increased.In these two systems,the oxygen could mi-grate to the thin liquid film on the steel surface through the air pores in the bentonite in the gas phase and undergo cathodic reduction.Meanwhile,it oxidized the ferrous hydrolysis products into ferric corro-sion products and formed a rust layer,which could block the diffusion of oxygen.At that moment,the cathodic process of NiCu steel corrosion changed to rust reduction.When the water content continually increased to 30%and 40%,the compacted bentonite was in a saturation state,and the corrosion rate of NiCu steel was significantly decreased.This was because most pores among the bentonite particles were occupied by a large amount of free water,which hindered the diffusion of oxygen and inhibited its cathodic reduction.Furthermore,it restrained the oxidation of ferrous corrosion products,which greatly weakened the cathodic depolarization of rust,leading to the cathodic process being dominated by the hydrogen evolution reaction.展开更多
Hydrogen evolution reaction(HER),zinc corrosion,and dendrites growth on zinc metal anode are the major issues limiting the practical applications of zinc-ion batteries.Herein,an in-situ physical/chemical cross-linked ...Hydrogen evolution reaction(HER),zinc corrosion,and dendrites growth on zinc metal anode are the major issues limiting the practical applications of zinc-ion batteries.Herein,an in-situ physical/chemical cross-linked hydrogel electrolyte(carrageenan/polyacrylamide/ZnSO_(4),denoted as CPZ)has been developed to stabilize the zinc anode-electrolyte interface,which can eliminate side reactions and prevent dendrites growth.The in-situ CPZ hydrogel electrolyte improves the reversibility of zinc anode due to eliminating side reactions caused by active water molecules.Furthermore,the electrostatic interaction between the SO_(4)^(-)groups in CPZ and Zn^(2+)can encourage the preferential deposition of zinc atoms on(002)crystal plane,which achieve dendrite-free and homogeneous zinc deposition.The in-situ hydrogel electrolyte offers a streamlined approach to battery manufacturing by allowing for direct integration into the battery.Subsequently,the Zn//Zn half battery with CPZ hydrogel electrolyte can enable an ultra-long cycle over 5500 h at a current density of 0.5 mA cm^(-2),and the Zn//Cu half battery reach an average coulombic efficiency of 99.37%.The Zn//V_(2)O_5-GO full battery with CPZ hydrogel electrolyte demonstrates94.5%of capacity retention after 2100 cycles.This study is expected to open new thought for the development of commercial hydrogel electrolytes for low-cost and long-life zinc-ion batteries.展开更多
In a multi-barrier system of geological disposal for high-level radioactive waste(HLW),it is considered that the disposal container is the first layer of protective barrier to HLW.Low carbon steel is considered as the...In a multi-barrier system of geological disposal for high-level radioactive waste(HLW),it is considered that the disposal container is the first layer of protective barrier to HLW.Low carbon steel is considered as the most promising candidate material for geological disposal container given its mechanical performances and cost-effectiveness.In a long-term geological disposal process,corrosion resistance and corrosion evolution law of low carbon steel in a deep geological environment determine the service life of the disposal containers.Based on a large number of electrochemical corrosion experimental results in a simulated groundwater environment in Beishan,a candidate site for geological disposal of HLW in China,this paper reviews corrosion behavior of low carbon steel from the principles of chemical thermodynamics and kinetics respectively.The effects of environmental factors such as deaeration,aeration,chemical compositions of groundwater on the evolution of corrosion products with immersion time were explored,and the secondary effect of corrosion product on the change of corrosion mode was proposed.In addition,by evaluating corrosion rate as a function of exposure time duration and simulated environment,the feasibility of manufacturing the geological disposal container with low carbon steel was introduced.展开更多
With issues of energy security and environmental crisis intensifying,we urgently need to develop energy storage systems with high energy density and high safety.Zinc–air batteries have attracted extensive attention f...With issues of energy security and environmental crisis intensifying,we urgently need to develop energy storage systems with high energy density and high safety.Zinc–air batteries have attracted extensive attention for their energy density,safety,and low cost,but problems with the zinc anode—such as hydrogen evolution,corrosion,passivation,dendrite proliferation,and deformation—have led to zinc–air batteries with low Coulombic efficiency and short cycle life;these remain the key obstacles hindering the batteries’further development.In this review paper,we briefly describe the reaction mechanism of zinc–air batteries,then summarize the strategies for solving the key issues in zinc anodes.These approaches are divided into three aspects:structural designs for the zinc anode;interface engineering;and electrolyte selection and optimization.We finish by offering some suggestions for future research directions to improve the zinc anode in zinc–air batteries.展开更多
基金financially supported by the National Natural Science Foundation of China (Nos. 51701222, U1867216 and 51471175)。
文摘The effects of bentonite content on the corrosion behavior of low carbon steel in 5 mM NaHCO3+ 1 mM NaCl + 1 mM Na2SO4 solution were investigated by electrochemical measurements combined with X-ray diffraction(XRD) and scanning electron microscopy(SEM). In the initial immersion stage, the cathodic process of low carbon steel corrosion was dominated by the reduction of dissolved oxygen, while it transformed to the reduction of ferric corrosion products with the immersion time. The presence of bentonite colloids could suppress the cathodic reduction of oxygen due to their barrier effect on the diffusion of oxygen. However, the barrier performance of bentonite layer was gradually deteriorated due to the coagulation and separation of bentonite colloids caused by the charge neutralization of iron corrosion products dissolved from the steel substrate. More bentonite colloids could maintain the barrier effect for a long time before it was deteriorated by the accumulation of corrosion products. Conversely,it could lose the performance completely, and the corrosion behavior of low carbon steel reverted to the same as that in the blank solution.
基金supported by the National Natural Science Foundation of China(Nos.52173304 and U1867216)the National Key R&D Program of China(No.2022YFB3207600)China Scholarship Council(No.2018SLJ014508).
文摘Buffer material and metal disposal containers are the key engineering barriers in the geological disposal of high-level radioactive waste.The durability of disposal containers largely depends on the water con-tent in buffer material.This work focused on investigating the corrosion evolution of NiCu low alloy steel in compacted GMZ bentonite with different water contents for 270 d by using weight loss,electrochemi-cal measurements,and various methods for analyzing corrosion products.As the water content increased from 13%to 20%,the water in the bentonite transformed from an unsaturated to a critical saturated state,and the corrosion rate of NiCu steel clearly increased.In these two systems,the oxygen could mi-grate to the thin liquid film on the steel surface through the air pores in the bentonite in the gas phase and undergo cathodic reduction.Meanwhile,it oxidized the ferrous hydrolysis products into ferric corro-sion products and formed a rust layer,which could block the diffusion of oxygen.At that moment,the cathodic process of NiCu steel corrosion changed to rust reduction.When the water content continually increased to 30%and 40%,the compacted bentonite was in a saturation state,and the corrosion rate of NiCu steel was significantly decreased.This was because most pores among the bentonite particles were occupied by a large amount of free water,which hindered the diffusion of oxygen and inhibited its cathodic reduction.Furthermore,it restrained the oxidation of ferrous corrosion products,which greatly weakened the cathodic depolarization of rust,leading to the cathodic process being dominated by the hydrogen evolution reaction.
基金supported by the Key Program of Natural Science Foundation of Gansu Province (23JRRA789)the Major Science and Technology Project of Gansu Province (22ZD6GA008)。
文摘Hydrogen evolution reaction(HER),zinc corrosion,and dendrites growth on zinc metal anode are the major issues limiting the practical applications of zinc-ion batteries.Herein,an in-situ physical/chemical cross-linked hydrogel electrolyte(carrageenan/polyacrylamide/ZnSO_(4),denoted as CPZ)has been developed to stabilize the zinc anode-electrolyte interface,which can eliminate side reactions and prevent dendrites growth.The in-situ CPZ hydrogel electrolyte improves the reversibility of zinc anode due to eliminating side reactions caused by active water molecules.Furthermore,the electrostatic interaction between the SO_(4)^(-)groups in CPZ and Zn^(2+)can encourage the preferential deposition of zinc atoms on(002)crystal plane,which achieve dendrite-free and homogeneous zinc deposition.The in-situ hydrogel electrolyte offers a streamlined approach to battery manufacturing by allowing for direct integration into the battery.Subsequently,the Zn//Zn half battery with CPZ hydrogel electrolyte can enable an ultra-long cycle over 5500 h at a current density of 0.5 mA cm^(-2),and the Zn//Cu half battery reach an average coulombic efficiency of 99.37%.The Zn//V_(2)O_5-GO full battery with CPZ hydrogel electrolyte demonstrates94.5%of capacity retention after 2100 cycles.This study is expected to open new thought for the development of commercial hydrogel electrolytes for low-cost and long-life zinc-ion batteries.
基金financially supported by the National Natural Science Foundation of China(Nos.U1867216,51701222 and 51471175)
文摘In a multi-barrier system of geological disposal for high-level radioactive waste(HLW),it is considered that the disposal container is the first layer of protective barrier to HLW.Low carbon steel is considered as the most promising candidate material for geological disposal container given its mechanical performances and cost-effectiveness.In a long-term geological disposal process,corrosion resistance and corrosion evolution law of low carbon steel in a deep geological environment determine the service life of the disposal containers.Based on a large number of electrochemical corrosion experimental results in a simulated groundwater environment in Beishan,a candidate site for geological disposal of HLW in China,this paper reviews corrosion behavior of low carbon steel from the principles of chemical thermodynamics and kinetics respectively.The effects of environmental factors such as deaeration,aeration,chemical compositions of groundwater on the evolution of corrosion products with immersion time were explored,and the secondary effect of corrosion product on the change of corrosion mode was proposed.In addition,by evaluating corrosion rate as a function of exposure time duration and simulated environment,the feasibility of manufacturing the geological disposal container with low carbon steel was introduced.
基金supported by the Natural Science Foundation of Fujian Province,China(2021J06001)National Natural Science Foundation of China(22372072)National Key Research and Development Program of China(2020YFB1505800).
文摘With issues of energy security and environmental crisis intensifying,we urgently need to develop energy storage systems with high energy density and high safety.Zinc–air batteries have attracted extensive attention for their energy density,safety,and low cost,but problems with the zinc anode—such as hydrogen evolution,corrosion,passivation,dendrite proliferation,and deformation—have led to zinc–air batteries with low Coulombic efficiency and short cycle life;these remain the key obstacles hindering the batteries’further development.In this review paper,we briefly describe the reaction mechanism of zinc–air batteries,then summarize the strategies for solving the key issues in zinc anodes.These approaches are divided into three aspects:structural designs for the zinc anode;interface engineering;and electrolyte selection and optimization.We finish by offering some suggestions for future research directions to improve the zinc anode in zinc–air batteries.
