Li-CO_(2) batteries provide an attractive and potential strategy for CO_(2) utilization as well as energy conversion and storage with high specific energy densities.However,the poor reversibility caused by the decompo...Li-CO_(2) batteries provide an attractive and potential strategy for CO_(2) utilization as well as energy conversion and storage with high specific energy densities.However,the poor reversibility caused by the decomposition obstacles of Li_(2)CO_(3) and C products is still a challenge for Li-CO_(2) batteries,which seriously influences its electrochemical performances.Herein,a free-standing MnOOH arrays cathode has been prepared and employed in Li-CO_(2) battery,which realizes a great improvement of electrochemical performances by adjusting the discharge products distribution.Experiments coupled with theoretical calculations verifies that the formation of Li-containing carbonaceous species(LiCO_(2),LiCO and Li_(2) CO_(3))bonded with MnOOH through Li ion regulates the nucleation behavior of Li_(2)CO_(3) and C,making them grown on MnOOH uniformly.The fine Li_(2) CO_(3) grains(with a size about 5 nm)embedded into carbon matrix greatly enlarges the contact interface between them,facilitating the transmission of electrons through the discharge products and finally improves CO_(2) evolution activity.This ingenious design strategy of regulating discharge products distribution to improve electrochemical performances provides a promising way to develop advanced Li-CO_(2) batteries.展开更多
By introducing the amine group into phosphorus extractant,a novel aminophosphine compound bis(2-ethylhexyl)((2-ethylhexylamino)methyl) phosphine oxide(DEHAPO,abbreviated as A) was synthesized for the extraction of cer...By introducing the amine group into phosphorus extractant,a novel aminophosphine compound bis(2-ethylhexyl)((2-ethylhexylamino)methyl) phosphine oxide(DEHAPO,abbreviated as A) was synthesized for the extraction of cerium(Ⅳ)(Ce(Ⅳ)) from sulfate medium(H2 SO4).The influence factors including extractant concentration,H2 SO4 concentration and temperature on the Ce(Ⅳ) extraction were investigated and discussed.It is found that the extraction ability of Ce(Ⅳ),thorium(Ⅳ)(Th(Ⅳ)) and rare earths(REs(Ⅲ))(La,Gd,Yb) decreases in sulphate medium in the following order:Ce(Ⅳ)> Th(Ⅳ)> REs(Ⅲ).The extraction process is an exothermic reaction and the thermodynamic parameters were calculated.The extracted complex of Ce(HSO4)2 SO4·A in loaded organic solution was identified by the slope methods and further proved by FT-IR spectral analysis.Stripping studies indicate that Ce(IV) can be effectively stripped from the organic phase.The results of separation factors(β) and saturation loading capacity demonstrate that DEHAPO could be used to selectively extract Ce(Ⅳ) from sulphate medium with high separation efficiency and good extraction ability.展开更多
By introducing the amine group into the structure of P227,a novel extractant 2-ethylhexyl((2-ethylhexylamino)methyl)phosphonic acid(EEAMPA,abbreviated as HA)was synthesized for the extraction and separation of trivale...By introducing the amine group into the structure of P227,a novel extractant 2-ethylhexyl((2-ethylhexylamino)methyl)phosphonic acid(EEAMPA,abbreviated as HA)was synthesized for the extraction and separation of trivalent rare earths(REs)from nitrate medium.The influence factors including extractant concentration,equilibrium time,HNO_(3)concentration,separation factors,cycle regeneration,stripping acidity,and actual leach liquor of metal ions,were studied systematically.The results show that the extraction ability of EEAMPA for REs decreases with increasing acidity.A possible extraction mechanism is proposed and the extracted species as REHA_(3)(NO_(3))are confirmed by the slope analysis method.The extraction equilibrium can reach faster than P227.It shows good chemical stability and cycling regeneration.Stripping studies show that HCl is an excellent stripping agent and REs can be effectively stripped from the organic phase.展开更多
Aprotic Li-CO_(2)batteries have attracted growing interest due to their high theoretical energy density and its ability to use green house gas CO_(2)for energy storage.However,the poor ability of activating CO_(2)in o...Aprotic Li-CO_(2)batteries have attracted growing interest due to their high theoretical energy density and its ability to use green house gas CO_(2)for energy storage.However,the poor ability of activating CO_(2)in organic electrolyte often leads to the premature termination of CO_(2)reduction reaction(CO_(2)RR)directly.Here in this work,cetyl trimethyl ammonium bromide(CTAB)was introduced into a dimethyl sulfoxide(DMSO)based Li-CO_(2)battery for the first time to enhance the CO_(2)RR.Significantly improved electrochemical performances,including reduced discharge over-potential and increased discharge capacity,can be achieved with the addition of CTAB.Ab initio molecular dynamics(AIMD)simulations show that quaternary ammonium group CTA^(+) can accelerate CO_(2)reduction process by forming more stable contact ion pair(CIP)with CO_(2)^(–),reducing the energy barrier for CO_(2)RR,thus improving the CO_(2)reduction process.In addition,adding CTA^(+) is also favorable for the solution-phase growth of discharge products because of the improved migration ability of stable CTA^(+)-CO_(2)^(–) CIP in the electrolyte,which is beneficial for improving the utilization ratio of cathode.This work could facilitate the development of CO_(2)RR by providing a novel understanding of CO_(2)RR mechanism in organic system.展开更多
The gadolinium extraction by the mixtures of p-phosphorylated calixarene and 1-phenyl-3-methyl-4-benzoylpyrazalone-5 from nitrate medium was studied,which indicated an obvious synergistic effect between these two extr...The gadolinium extraction by the mixtures of p-phosphorylated calixarene and 1-phenyl-3-methyl-4-benzoylpyrazalone-5 from nitrate medium was studied,which indicated an obvious synergistic effect between these two extractants.The extractants exhibit no interaction with each other before the metal extraction.Gadolinium(Ⅲ)was extracted by the species of Ln(PMBP)_(2)L_(2)(NO_(3))instead of Ln(PMBP)_(3)•(HPMBP)or Ln(NO_(3))_(3)•2L which are extracted by HPMBP or L alone.Thermodynamic functions(ΔG,ΔH,ΔS)were calculated.The extraction of other rare earths was also investigated and compared.Possible single rare earth separation was discussed.展开更多
基金financially supported by the National Natural Science Foundation of China(Grant Nos.21701145 and 21701146,21671176)China Postdoctoral Science Foundation(Grant Nos.2017M610459 and 2018T110739)。
文摘Li-CO_(2) batteries provide an attractive and potential strategy for CO_(2) utilization as well as energy conversion and storage with high specific energy densities.However,the poor reversibility caused by the decomposition obstacles of Li_(2)CO_(3) and C products is still a challenge for Li-CO_(2) batteries,which seriously influences its electrochemical performances.Herein,a free-standing MnOOH arrays cathode has been prepared and employed in Li-CO_(2) battery,which realizes a great improvement of electrochemical performances by adjusting the discharge products distribution.Experiments coupled with theoretical calculations verifies that the formation of Li-containing carbonaceous species(LiCO_(2),LiCO and Li_(2) CO_(3))bonded with MnOOH through Li ion regulates the nucleation behavior of Li_(2)CO_(3) and C,making them grown on MnOOH uniformly.The fine Li_(2) CO_(3) grains(with a size about 5 nm)embedded into carbon matrix greatly enlarges the contact interface between them,facilitating the transmission of electrons through the discharge products and finally improves CO_(2) evolution activity.This ingenious design strategy of regulating discharge products distribution to improve electrochemical performances provides a promising way to develop advanced Li-CO_(2) batteries.
基金Project supported by the National Natural Science Foundation of China(21701146)the National Science Foundation for Post-doctoral Scientists of China(2018M632798)the Open Funds of the State Key Laboratory of Rare Earth Resource(RERU2017019)。
文摘By introducing the amine group into phosphorus extractant,a novel aminophosphine compound bis(2-ethylhexyl)((2-ethylhexylamino)methyl) phosphine oxide(DEHAPO,abbreviated as A) was synthesized for the extraction of cerium(Ⅳ)(Ce(Ⅳ)) from sulfate medium(H2 SO4).The influence factors including extractant concentration,H2 SO4 concentration and temperature on the Ce(Ⅳ) extraction were investigated and discussed.It is found that the extraction ability of Ce(Ⅳ),thorium(Ⅳ)(Th(Ⅳ)) and rare earths(REs(Ⅲ))(La,Gd,Yb) decreases in sulphate medium in the following order:Ce(Ⅳ)> Th(Ⅳ)> REs(Ⅲ).The extraction process is an exothermic reaction and the thermodynamic parameters were calculated.The extracted complex of Ce(HSO4)2 SO4·A in loaded organic solution was identified by the slope methods and further proved by FT-IR spectral analysis.Stripping studies indicate that Ce(IV) can be effectively stripped from the organic phase.The results of separation factors(β) and saturation loading capacity demonstrate that DEHAPO could be used to selectively extract Ce(Ⅳ) from sulphate medium with high separation efficiency and good extraction ability.
基金Project supported by the National Natural Science Foundation of China(21701146)the National Science Foundation for Post-doctoral Scientists of China(2018M632798)the Open Funds of the State Key Laboratory of Rare Earth Resource(RERU2017019)。
文摘By introducing the amine group into the structure of P227,a novel extractant 2-ethylhexyl((2-ethylhexylamino)methyl)phosphonic acid(EEAMPA,abbreviated as HA)was synthesized for the extraction and separation of trivalent rare earths(REs)from nitrate medium.The influence factors including extractant concentration,equilibrium time,HNO_(3)concentration,separation factors,cycle regeneration,stripping acidity,and actual leach liquor of metal ions,were studied systematically.The results show that the extraction ability of EEAMPA for REs decreases with increasing acidity.A possible extraction mechanism is proposed and the extracted species as REHA_(3)(NO_(3))are confirmed by the slope analysis method.The extraction equilibrium can reach faster than P227.It shows good chemical stability and cycling regeneration.Stripping studies show that HCl is an excellent stripping agent and REs can be effectively stripped from the organic phase.
基金National Science Foundation of China(Nos.21701145 and 21701146)China Postdoctoral Science Foundation(Nos.2017M610459 and 2018T110739)。
文摘Aprotic Li-CO_(2)batteries have attracted growing interest due to their high theoretical energy density and its ability to use green house gas CO_(2)for energy storage.However,the poor ability of activating CO_(2)in organic electrolyte often leads to the premature termination of CO_(2)reduction reaction(CO_(2)RR)directly.Here in this work,cetyl trimethyl ammonium bromide(CTAB)was introduced into a dimethyl sulfoxide(DMSO)based Li-CO_(2)battery for the first time to enhance the CO_(2)RR.Significantly improved electrochemical performances,including reduced discharge over-potential and increased discharge capacity,can be achieved with the addition of CTAB.Ab initio molecular dynamics(AIMD)simulations show that quaternary ammonium group CTA^(+) can accelerate CO_(2)reduction process by forming more stable contact ion pair(CIP)with CO_(2)^(–),reducing the energy barrier for CO_(2)RR,thus improving the CO_(2)reduction process.In addition,adding CTA^(+) is also favorable for the solution-phase growth of discharge products because of the improved migration ability of stable CTA^(+)-CO_(2)^(–) CIP in the electrolyte,which is beneficial for improving the utilization ratio of cathode.This work could facilitate the development of CO_(2)RR by providing a novel understanding of CO_(2)RR mechanism in organic system.
基金This work was supported by 973 Program(No.2012CBA01206)the National Natural Science Foundation of China(Nos.21221061,21301170 and 51222404).
文摘The gadolinium extraction by the mixtures of p-phosphorylated calixarene and 1-phenyl-3-methyl-4-benzoylpyrazalone-5 from nitrate medium was studied,which indicated an obvious synergistic effect between these two extractants.The extractants exhibit no interaction with each other before the metal extraction.Gadolinium(Ⅲ)was extracted by the species of Ln(PMBP)_(2)L_(2)(NO_(3))instead of Ln(PMBP)_(3)•(HPMBP)or Ln(NO_(3))_(3)•2L which are extracted by HPMBP or L alone.Thermodynamic functions(ΔG,ΔH,ΔS)were calculated.The extraction of other rare earths was also investigated and compared.Possible single rare earth separation was discussed.
