A process capable of simultaneously oxidizing NO, SO2, and Hg^0 was proposed, using a nigh-voltage and short-duration positive pulsed corona discharge. By focusing on NO, SO2, and Hg^0 oxidation efficiencies, the infl...A process capable of simultaneously oxidizing NO, SO2, and Hg^0 was proposed, using a nigh-voltage and short-duration positive pulsed corona discharge. By focusing on NO, SO2, and Hg^0 oxidation efficiencies, the influences of pulse peak voltage, pulse frequency, initial concentration, electrode number, residence time and water vapor addition were investigated. The results indicate that NO, SO2 and Hg^0 oxidation efficiencies depend primarily on the radicals (OH, HO2, O) and the active species (O3, H2O2, etc.) produced by the pulsed corona discharge. The NO, SO2 and Hg^0 oxidation efficiencies could be improved as pulse peak voltage, pulse frequency, electrode number and residence time increased, but they were reduced with increasing initial concentrations. By adding water vapor, the SO2 oxidation efficiency was improved remarkably, while the NO oxidation efficiency decreased slightly. In our experiments, the simultaneous NO, SO2, and Hg^0 oxidation efficiencies reached to 40%, 98%, and 55% with the initial concentrations 479 mg/m^3, 1040 mg/m^3, and 15.0 μg/m^3, respectively.展开更多
In this study,a series of CuCl_(2)-modified MnO_(x)-CeO_(x)nanorods were synthesized for the oxidation of Hg^(0).The addition of CuCl_(2)resulted in an enhancement in the catalyst’s Hg^(0)oxidation ability,and Hg^(0)...In this study,a series of CuCl_(2)-modified MnO_(x)-CeO_(x)nanorods were synthesized for the oxidation of Hg^(0).The addition of CuCl_(2)resulted in an enhancement in the catalyst’s Hg^(0)oxidation ability,and Hg^(0)oxidation efficiency reached>97%from 150 to 250°C.In the MnO_(x)-CeO_(x)catalysts,Mn^(4+)played the role of the active species for Hg^(0)oxidization,but in the CuCl_(2)-doped catalysts Cl−also contributed to Hg^(0)oxidation,conferring the superior performance of these samples.The introduction of SO_(2) led to a decrease in the availability of Mn^(4+),and the Hg^(0)oxidation efficiency of MnO_(x)-CeO_(x)decreased from about 100%to about 78%.By contrast,CuCl_(2)-promoted samples maintained a Hg^(0)oxidation efficiency of about 100%during the SO_(2) deactivation cycle due to the high reactivity of Cl−.展开更多
Effects of the voltage waveform, discharge tooth wheel number and CO2/NO/SO2 concentration in the simulated flue gas on Hg^0 oxidation were investigated using a link tooth wheel-cylinder reactor energized by different...Effects of the voltage waveform, discharge tooth wheel number and CO2/NO/SO2 concentration in the simulated flue gas on Hg^0 oxidation were investigated using a link tooth wheel-cylinder reactor energized by different high voltage power supplies. Negative DC discharge induced more ozone production and a higher Hg^0 oxidation efficiency than positive DC discharge and 12 kHz AC discharge. The discharge tooth wheel number had almost no effect on the maximum Hg^0 oxidation efficiency. The allowable supplied voltage decreased with the increase of discharge tooth wheel number. CO2 could stabilize the discharge process and increase the maximum voltage for a stable discharge. It has also been found that NO consumed O3 induced by high voltage discharge, thereby decreased Hg^0 oxidation efficiency; while SO2 had a slight promoting effect on Hg^0 oxidation.展开更多
Although CoO is a promising electrode material for supercapacitors due to its high theoretical capacitance,the practical applications still suffering from inferior electrochemical activity owing to its low electrical ...Although CoO is a promising electrode material for supercapacitors due to its high theoretical capacitance,the practical applications still suffering from inferior electrochemical activity owing to its low electrical conductivity,poor structural stability and inefficient nanostructure.Herein,we report a novel Cu0/Cu+co-doped CoO composite with adjustable metallic Cu0 and ion Cu+via a facile strategy.Through interior(Cu+)and exterior(Cu0)decoration of CoO,the electrochemical performance of CoO electrode has been significantly improved due to both the beneficial flower-like nanostructure and the synergetic effect of Cu0/Cu+co-doping,which results in a significantly enhanced specific capacitance(695 F g^(-1) at 1 A g^(-1))and high cyclic stability(93.4%retention over 10,000 cycles)than pristine CoO.Furthermore,this co-doping strategy is also applicable to other transition metal oxide(NiO)with enhanced electrochemical performance.In addition,an asymmetric hybrid supercapacitor was assembled using the Cu0/Cu+co-doped CoO electrode and active carbon,which delivers a remarkable maximal energy density(35 Wh kg^(-1)),exceptional power density(16 kW kg^(-1))and ultralong cycle life(91.5%retention over 10,000 cycles).Theoretical calculations further verify that the co-doping of Cu^(0)/Cu^(+)can tune the electronic structure of CoO and improve the conductivity and electron transport.This study demonstrates a facile and favorable strategy to enhance the electrochemical performance of transition metal oxide electrode materials.展开更多
基金supported by the Science and Technology Research of Department of Education of China (No. 0305,03087)
文摘A process capable of simultaneously oxidizing NO, SO2, and Hg^0 was proposed, using a nigh-voltage and short-duration positive pulsed corona discharge. By focusing on NO, SO2, and Hg^0 oxidation efficiencies, the influences of pulse peak voltage, pulse frequency, initial concentration, electrode number, residence time and water vapor addition were investigated. The results indicate that NO, SO2 and Hg^0 oxidation efficiencies depend primarily on the radicals (OH, HO2, O) and the active species (O3, H2O2, etc.) produced by the pulsed corona discharge. The NO, SO2 and Hg^0 oxidation efficiencies could be improved as pulse peak voltage, pulse frequency, electrode number and residence time increased, but they were reduced with increasing initial concentrations. By adding water vapor, the SO2 oxidation efficiency was improved remarkably, while the NO oxidation efficiency decreased slightly. In our experiments, the simultaneous NO, SO2, and Hg^0 oxidation efficiencies reached to 40%, 98%, and 55% with the initial concentrations 479 mg/m^3, 1040 mg/m^3, and 15.0 μg/m^3, respectively.
基金supported by the Zhejiang Provincial Natural Science Foundation of China(No.LQ22E060003)the General Research Projects of Zhejiang Provincial Department of Education in 2023(No.Y202353660)the Public Welfare Science and Technology Project of Ningbo City(No.202002N3105),China.
文摘In this study,a series of CuCl_(2)-modified MnO_(x)-CeO_(x)nanorods were synthesized for the oxidation of Hg^(0).The addition of CuCl_(2)resulted in an enhancement in the catalyst’s Hg^(0)oxidation ability,and Hg^(0)oxidation efficiency reached>97%from 150 to 250°C.In the MnO_(x)-CeO_(x)catalysts,Mn^(4+)played the role of the active species for Hg^(0)oxidization,but in the CuCl_(2)-doped catalysts Cl−also contributed to Hg^(0)oxidation,conferring the superior performance of these samples.The introduction of SO_(2) led to a decrease in the availability of Mn^(4+),and the Hg^(0)oxidation efficiency of MnO_(x)-CeO_(x)decreased from about 100%to about 78%.By contrast,CuCl_(2)-promoted samples maintained a Hg^(0)oxidation efficiency of about 100%during the SO_(2) deactivation cycle due to the high reactivity of Cl−.
基金support for this work provided by the High-Tech Research and Development Program (863) of China (No. 2007AA06Z313)the Beijing Municipal Natural Science Foundation (No.8072017)
文摘Effects of the voltage waveform, discharge tooth wheel number and CO2/NO/SO2 concentration in the simulated flue gas on Hg^0 oxidation were investigated using a link tooth wheel-cylinder reactor energized by different high voltage power supplies. Negative DC discharge induced more ozone production and a higher Hg^0 oxidation efficiency than positive DC discharge and 12 kHz AC discharge. The discharge tooth wheel number had almost no effect on the maximum Hg^0 oxidation efficiency. The allowable supplied voltage decreased with the increase of discharge tooth wheel number. CO2 could stabilize the discharge process and increase the maximum voltage for a stable discharge. It has also been found that NO consumed O3 induced by high voltage discharge, thereby decreased Hg^0 oxidation efficiency; while SO2 had a slight promoting effect on Hg^0 oxidation.
基金financially supported by the National Science Foundation of China(Grant No.11804106)。
文摘Although CoO is a promising electrode material for supercapacitors due to its high theoretical capacitance,the practical applications still suffering from inferior electrochemical activity owing to its low electrical conductivity,poor structural stability and inefficient nanostructure.Herein,we report a novel Cu0/Cu+co-doped CoO composite with adjustable metallic Cu0 and ion Cu+via a facile strategy.Through interior(Cu+)and exterior(Cu0)decoration of CoO,the electrochemical performance of CoO electrode has been significantly improved due to both the beneficial flower-like nanostructure and the synergetic effect of Cu0/Cu+co-doping,which results in a significantly enhanced specific capacitance(695 F g^(-1) at 1 A g^(-1))and high cyclic stability(93.4%retention over 10,000 cycles)than pristine CoO.Furthermore,this co-doping strategy is also applicable to other transition metal oxide(NiO)with enhanced electrochemical performance.In addition,an asymmetric hybrid supercapacitor was assembled using the Cu0/Cu+co-doped CoO electrode and active carbon,which delivers a remarkable maximal energy density(35 Wh kg^(-1)),exceptional power density(16 kW kg^(-1))and ultralong cycle life(91.5%retention over 10,000 cycles).Theoretical calculations further verify that the co-doping of Cu^(0)/Cu^(+)can tune the electronic structure of CoO and improve the conductivity and electron transport.This study demonstrates a facile and favorable strategy to enhance the electrochemical performance of transition metal oxide electrode materials.