Aqueous rechargeable zinc batteries are very attractive for energy storage applications due to their low cost and high safety.However,low operating voltages limit their further development.For the first time,this work...Aqueous rechargeable zinc batteries are very attractive for energy storage applications due to their low cost and high safety.However,low operating voltages limit their further development.For the first time,this work proposes a unique approach to increase the voltages of aqueous zinc batteries by using tri-functional metallic bipolar electrode with good electrochemical activity and ultrahigh electronic conductivity,which not only participates in redox reactions,but also functions as an electrical highway for charge transport.Furthermore,bipolar electrode can replace expensive ion selective membrane to separate electrolytes with different pH;thus,redox couples with higher potential in acid condition and Zn=Zn(OH)^(2-)_(4) couple with lower potential in alkaline condition can be employed together,leading to high voltages of aqueous zinc batteries.Herein,two types of metallic bipolar electrodes of Cu and Ag are utilized based on three kinds of aqueous zinc batteries:Zn–MnO_(2),Zn–I_(2),and Zn–Br_(2).The voltage of aqueous Zn–MnO_(2) battery is raised to 1.84 V by employing one Cu bipolar electrode,which shows no capacity attenuation after 3500 cycles.Moreover,the other Ag bipolar electrode can be adopted to successfully construct Zn–I_(2) and Zn–Br_(2) batteries exhibiting much higher voltages of 2.44 and 2.67 V,which also show no obvious capacity degradation for 1000 and 800 cycles,representing decent cycle stability.Since bipolar electrode can be applied in a large family of aqueous batteries,this work offers an elaborate high-voltage concept based on tri-functional metallic bipolar electrode as a model system to open a door to explore high-voltage aqueous batteries.展开更多
In this paper, we study the characteristics of atmospheric-pressure pulsed dielectric barrier discharge (DBD) under the needle-plate electrode configuration using a one-dimensional self-consistent fluid model. The r...In this paper, we study the characteristics of atmospheric-pressure pulsed dielectric barrier discharge (DBD) under the needle-plate electrode configuration using a one-dimensional self-consistent fluid model. The results show that, the DBDs driven by positive pulse, negative pulse and bipolar pulse possess different behaviors. Moreover, the two discharges appearing at the rising and the falling phases of per voltage pulse also have different discharge regimes. For the case of the positive pulse, the breakdown field is much lower than that of the negative pulse, and its propagation characteristic is different from the negative pulse DBD. When the DBD is driven by a bipolar pulse voltage, there exists the interaction between the positive and negative pulses, resulting in the decrease of the breakdown field of the negative pulse DBD and causing the change of the discharge behaviors. In addition, the effects of the discharge parameters on the behaviors of pulsed DBD in the needle-plate electrode configuration are also studied.展开更多
The design of electrodes is crucial to electrocoagulation process(EC),specifically,with respect to pollutant removal and energy consumption.During EC,the mechanisms for interaction between different electrode arrangem...The design of electrodes is crucial to electrocoagulation process(EC),specifically,with respect to pollutant removal and energy consumption.During EC,the mechanisms for interaction between different electrode arrangement and electrode reactions remain unclear.This work presents an integrated EC process based on horizontal bipolar electrodes(BPEs).In the electrochemical cell,the graphite plates are used as driving cathode while either Fe or A1 plates serves as driving anode and BPEs.The BPEs are placed horizontally between the driving electrodes.For municipal wastewater treatment,the pollutant removal efficiency and energy consumption in different configurations of twodimension electrocoagulation(2D-EC)system with horizontal BPEs were investigated.The removal efficiency of turbidity,total phosphorus and total organic carbon increased significantly with the number of BPEs.Noted that the energy consumption for TP removal decreased by 75.2%with Fe driving anode and 81.5%with A1 driving anode than those of 2D-EC,respectively.In addition,the physical field simulation suggested the distributions of potential and current in electrolyte and that of induced charge density on BPE surface.This work provides a visual theoretical guidance to predict the distribution of reactions on BPEs for enhanced pollutant removal and energy saving based on electrocoagulation process for municipal wastewater treatment.展开更多
This research investigates a capacitive deionization method for salinity reduction in a batch reactor as a new approach for desalination.Reductions of cost and energy compared with conventional desalination methods ar...This research investigates a capacitive deionization method for salinity reduction in a batch reactor as a new approach for desalination.Reductions of cost and energy compared with conventional desalination methods are the significant advantages of this approach.In this research,experiments were performed with a pair of graphite bipolar electrodes that were coated with a one-gram activated carbon solution.After completing preliminary tests,the impacts of four parameters on electrical conductivity reduction,including(1)the initial concentration of feed solution,(2)the duration of the tests,(3)the applied voltage,and(4)the pH of the solution,were examined.The results show that the maximum efficiency of electrical conductivity reduction in this laboratory-scale reactor is about 55%.Furthermore,the effects of the initial concentration of feed solution are more significant than the other parameters.Thus,using the capacitive deionization method for water desalination with low and moderate salt concentrations(i.e.,brackish water)is proposed as an affordable method.Compared with conventional desalination methods,capacitive deionization is not only more efficient but also potentially more environmentally friendly.展开更多
基金The authors would like to acknowledge the financial support sponsored by Ten-thousand Talents Program,K.C.Wong Pioneer Talent Program,Shanghai Pujiang Program (Grant No.19PJ1410600)the National Natural Science Foundation of China (Grant No.51901240).
文摘Aqueous rechargeable zinc batteries are very attractive for energy storage applications due to their low cost and high safety.However,low operating voltages limit their further development.For the first time,this work proposes a unique approach to increase the voltages of aqueous zinc batteries by using tri-functional metallic bipolar electrode with good electrochemical activity and ultrahigh electronic conductivity,which not only participates in redox reactions,but also functions as an electrical highway for charge transport.Furthermore,bipolar electrode can replace expensive ion selective membrane to separate electrolytes with different pH;thus,redox couples with higher potential in acid condition and Zn=Zn(OH)^(2-)_(4) couple with lower potential in alkaline condition can be employed together,leading to high voltages of aqueous zinc batteries.Herein,two types of metallic bipolar electrodes of Cu and Ag are utilized based on three kinds of aqueous zinc batteries:Zn–MnO_(2),Zn–I_(2),and Zn–Br_(2).The voltage of aqueous Zn–MnO_(2) battery is raised to 1.84 V by employing one Cu bipolar electrode,which shows no capacity attenuation after 3500 cycles.Moreover,the other Ag bipolar electrode can be adopted to successfully construct Zn–I_(2) and Zn–Br_(2) batteries exhibiting much higher voltages of 2.44 and 2.67 V,which also show no obvious capacity degradation for 1000 and 800 cycles,representing decent cycle stability.Since bipolar electrode can be applied in a large family of aqueous batteries,this work offers an elaborate high-voltage concept based on tri-functional metallic bipolar electrode as a model system to open a door to explore high-voltage aqueous batteries.
基金supported by National Natural Science Foundation of China(No.11405022)
文摘In this paper, we study the characteristics of atmospheric-pressure pulsed dielectric barrier discharge (DBD) under the needle-plate electrode configuration using a one-dimensional self-consistent fluid model. The results show that, the DBDs driven by positive pulse, negative pulse and bipolar pulse possess different behaviors. Moreover, the two discharges appearing at the rising and the falling phases of per voltage pulse also have different discharge regimes. For the case of the positive pulse, the breakdown field is much lower than that of the negative pulse, and its propagation characteristic is different from the negative pulse DBD. When the DBD is driven by a bipolar pulse voltage, there exists the interaction between the positive and negative pulses, resulting in the decrease of the breakdown field of the negative pulse DBD and causing the change of the discharge behaviors. In addition, the effects of the discharge parameters on the behaviors of pulsed DBD in the needle-plate electrode configuration are also studied.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.51822806,51678184 and 51761145031)Fundamental Research Funds for the Central Universities(Grant HIT.BRETIV.201905).
文摘The design of electrodes is crucial to electrocoagulation process(EC),specifically,with respect to pollutant removal and energy consumption.During EC,the mechanisms for interaction between different electrode arrangement and electrode reactions remain unclear.This work presents an integrated EC process based on horizontal bipolar electrodes(BPEs).In the electrochemical cell,the graphite plates are used as driving cathode while either Fe or A1 plates serves as driving anode and BPEs.The BPEs are placed horizontally between the driving electrodes.For municipal wastewater treatment,the pollutant removal efficiency and energy consumption in different configurations of twodimension electrocoagulation(2D-EC)system with horizontal BPEs were investigated.The removal efficiency of turbidity,total phosphorus and total organic carbon increased significantly with the number of BPEs.Noted that the energy consumption for TP removal decreased by 75.2%with Fe driving anode and 81.5%with A1 driving anode than those of 2D-EC,respectively.In addition,the physical field simulation suggested the distributions of potential and current in electrolyte and that of induced charge density on BPE surface.This work provides a visual theoretical guidance to predict the distribution of reactions on BPEs for enhanced pollutant removal and energy saving based on electrocoagulation process for municipal wastewater treatment.
文摘This research investigates a capacitive deionization method for salinity reduction in a batch reactor as a new approach for desalination.Reductions of cost and energy compared with conventional desalination methods are the significant advantages of this approach.In this research,experiments were performed with a pair of graphite bipolar electrodes that were coated with a one-gram activated carbon solution.After completing preliminary tests,the impacts of four parameters on electrical conductivity reduction,including(1)the initial concentration of feed solution,(2)the duration of the tests,(3)the applied voltage,and(4)the pH of the solution,were examined.The results show that the maximum efficiency of electrical conductivity reduction in this laboratory-scale reactor is about 55%.Furthermore,the effects of the initial concentration of feed solution are more significant than the other parameters.Thus,using the capacitive deionization method for water desalination with low and moderate salt concentrations(i.e.,brackish water)is proposed as an affordable method.Compared with conventional desalination methods,capacitive deionization is not only more efficient but also potentially more environmentally friendly.