Nitrate synthesis is an important process for agriculture and industry,but suffers from energy-intensive steps including the synthesis and subsequent oxidation of ammonia.Herein,we present a selective N_(2)transformat...Nitrate synthesis is an important process for agriculture and industry,but suffers from energy-intensive steps including the synthesis and subsequent oxidation of ammonia.Herein,we present a selective N_(2)transformation to nitrate by guiding the charge neutralization of self-electrified water microdroplets in an artificial cloud generated with the portable ultrasonic atomizer.The electron and ion transfer in the charge neutralization of water microdroplets on metal micromesh enables an up to~40-fold increase in the reactivity of nitrate formation reaction driven by ultrasonic energy.A robust semi-continuous N_(2)oxidation by a Ni-mesh-screened cloud system was achieved,providing nitrate with~12 mM concentration every 20 h.These findings emphasize the potential of harnessing the microdroplet-mediated cloud electrochemistry of N_(2)in decentralizing the current mass production of fertilizer.展开更多
The purity of electronic-grade chemicals significantly impacts electronic components.Although crystallization has been used to purify cerium ammonium nitrate(CAN),the impurity removal mechanism underlying different cr...The purity of electronic-grade chemicals significantly impacts electronic components.Although crystallization has been used to purify cerium ammonium nitrate(CAN),the impurity removal mechanism underlying different crystallization parameters remains unclear.Traditional analytical methods of inductively coupled plasma mass spectrometry(ICP-MS)have problems in detecting trace Fe accurately,because of the high concentration of Ce and interference of polyatomic ions.Therefore,this study developed a new method integrating the standard addition and internal standard methods and explored the role of the kinetic energy discrimination mode.This new approach effectively overcomes Ce-related matrix interference and fills the gap in ultra-trace impurity detection.Furthermore,the study investigated the effects of cooling rate,seed mass loading and seed size on the removal of Fe impurity.The seed mass loading affects the average crystal size through regulating secondary nucleation and crystal growth.The removal of Fe in CAN is determined by surface adsorption and agglomeration.Under the condition of the cooling rate of 0.2 K·min^(-1),and addition of 0.5%(mass)600-680 μm seeds,the Fe content is the lowest,at only 0.24 mg·L^(-1),and the Fe removal rate reaches 92.28%.展开更多
Layered ammonium vanadate has become a promising cathode material for aqueous zinc ion batteries(ZIBs)due to its small mass and large ionic radius of ammonium ions as well as the consequent large layer spacing and hig...Layered ammonium vanadate has become a promising cathode material for aqueous zinc ion batteries(ZIBs)due to its small mass and large ionic radius of ammonium ions as well as the consequent large layer spacing and high specific capacity.However,the irreversible de-ammoniation caused by N·H···O bonds damaged would impair cycle life of ZIBs and the strong electrostatic interaction between Zn^(2+)and V-O frame could slower the mobility of Zn^(2+).Furthermore,the thermal instability of ammonium vanadate also limits the use of common carbon coating modification method to solve the problem.Herein,V_(2)CT_(X)MXene was innovatively selected as a bifunctional source to in-situ derivatized(NH_(4))_(2)V_(8)O_(20)·x H_(2)O with amorphous carbon-coated(NHVO@C)via one-step hydrothermal method in relatively moderate temperature.The amorphous carbon shell derived from the V_(2)CT_(X)MXene as a conductive framework to effectively improve the diffusion kinetics of Zn^(2+)and the robust carbon skeleton could alleviate the ammonium dissolution during long-term cycling.As a result,zinc ion batteries using NHVO@C as cathode exhibit superior electrochemical performance.Moreover,the assembled foldable or high loading(10.2 mg/cm^(2))soft-packed ZIBs further demonstrates its practical application.This study provided new insights into the development of the carbon cladding process for thermally unstable materials in moderate temperatures.展开更多
Thermodynamic simulation was conducted to design a new process of stepwise precipitating NH_(4)VO_(3)and NaHCO_(3)from regulating the CO_(2)carbonation of Na_(3)VO_(4)solution.Firstly,a new V(V)speciation model for th...Thermodynamic simulation was conducted to design a new process of stepwise precipitating NH_(4)VO_(3)and NaHCO_(3)from regulating the CO_(2)carbonation of Na_(3)VO_(4)solution.Firstly,a new V(V)speciation model for the aqueous solution containing vanadate and carbonate is established by using the Bromley-Zemaitis activity coefficient model.Subsequently,thermodynamic equilibrium calculations are conducted to clarify the behavior of vanadium,carbon,sodium,and impurity species in atmospheric or high-pressure carbonation.To ensure the purity and recovery of vanadium products,Na_(3)VO_(4)solution is initially carbonated to the pH of 9.3-9.4,followed by precipitating NH_(4)VO_(3)by adding(NH_(4))_(2)CO_(3).After vanadium precipitation,the solution is deeply carbonated to the final pH of 7.3-7.5 to precipitate NaHCO_(3),and the remaining solution is recycled to dissolve Na_(3)VO_(4)crystals.Finally,verification experiments demonstrate that 99.1%of vanadium and 91.4%of sodium in the solution are recovered in the form of NH_(4)VO_(3)and NaHCO_(3),respectively.展开更多
基金supported by the National Key R&D Program of China(2022YFA1504603)the National Natural Science Foundation of China(22025206,22172163)+1 种基金the Dalian Innovation Support Plan for High Level Talents(2022RG13)the Fundamental Research Funds for the Central Universities(20720220008)。
文摘Nitrate synthesis is an important process for agriculture and industry,but suffers from energy-intensive steps including the synthesis and subsequent oxidation of ammonia.Herein,we present a selective N_(2)transformation to nitrate by guiding the charge neutralization of self-electrified water microdroplets in an artificial cloud generated with the portable ultrasonic atomizer.The electron and ion transfer in the charge neutralization of water microdroplets on metal micromesh enables an up to~40-fold increase in the reactivity of nitrate formation reaction driven by ultrasonic energy.A robust semi-continuous N_(2)oxidation by a Ni-mesh-screened cloud system was achieved,providing nitrate with~12 mM concentration every 20 h.These findings emphasize the potential of harnessing the microdroplet-mediated cloud electrochemistry of N_(2)in decentralizing the current mass production of fertilizer.
基金the National Natural Science Foundation of China(22308358,22208346,22421003)IPE Project for Frontier Basic Research(QYJC-2023-05)+1 种基金National Key Research and Development Program(2022YFC3902701)CAS Project for Young Scientists in Basic Research(YSBR-038).
文摘The purity of electronic-grade chemicals significantly impacts electronic components.Although crystallization has been used to purify cerium ammonium nitrate(CAN),the impurity removal mechanism underlying different crystallization parameters remains unclear.Traditional analytical methods of inductively coupled plasma mass spectrometry(ICP-MS)have problems in detecting trace Fe accurately,because of the high concentration of Ce and interference of polyatomic ions.Therefore,this study developed a new method integrating the standard addition and internal standard methods and explored the role of the kinetic energy discrimination mode.This new approach effectively overcomes Ce-related matrix interference and fills the gap in ultra-trace impurity detection.Furthermore,the study investigated the effects of cooling rate,seed mass loading and seed size on the removal of Fe impurity.The seed mass loading affects the average crystal size through regulating secondary nucleation and crystal growth.The removal of Fe in CAN is determined by surface adsorption and agglomeration.Under the condition of the cooling rate of 0.2 K·min^(-1),and addition of 0.5%(mass)600-680 μm seeds,the Fe content is the lowest,at only 0.24 mg·L^(-1),and the Fe removal rate reaches 92.28%.
基金financially supported by the National Natural Science Foundation of China(Nos.52402271,22005167 and52302273)the Youth Innovation Team Project for Talent Introduction and Cultivation in Universities of Shandong Province(No.2024KJH129)+2 种基金the Taishan Scholar Project of Shandong Provinceof China(Nos.tsqn202211160,tsqn202312199)Shandong Provincial Natural Science Foundation of China(Nos.ZR2022QE003 and ZR2023QE176)China Postdoctoral Science Foundation(No.2023M741810)。
文摘Layered ammonium vanadate has become a promising cathode material for aqueous zinc ion batteries(ZIBs)due to its small mass and large ionic radius of ammonium ions as well as the consequent large layer spacing and high specific capacity.However,the irreversible de-ammoniation caused by N·H···O bonds damaged would impair cycle life of ZIBs and the strong electrostatic interaction between Zn^(2+)and V-O frame could slower the mobility of Zn^(2+).Furthermore,the thermal instability of ammonium vanadate also limits the use of common carbon coating modification method to solve the problem.Herein,V_(2)CT_(X)MXene was innovatively selected as a bifunctional source to in-situ derivatized(NH_(4))_(2)V_(8)O_(20)·x H_(2)O with amorphous carbon-coated(NHVO@C)via one-step hydrothermal method in relatively moderate temperature.The amorphous carbon shell derived from the V_(2)CT_(X)MXene as a conductive framework to effectively improve the diffusion kinetics of Zn^(2+)and the robust carbon skeleton could alleviate the ammonium dissolution during long-term cycling.As a result,zinc ion batteries using NHVO@C as cathode exhibit superior electrochemical performance.Moreover,the assembled foldable or high loading(10.2 mg/cm^(2))soft-packed ZIBs further demonstrates its practical application.This study provided new insights into the development of the carbon cladding process for thermally unstable materials in moderate temperatures.
基金the financial supports from the National Natural Science Foundation of China(No.22078343)Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA0430103)the National Key Research and Development Program of China(No.2018YFC1900502)。
文摘Thermodynamic simulation was conducted to design a new process of stepwise precipitating NH_(4)VO_(3)and NaHCO_(3)from regulating the CO_(2)carbonation of Na_(3)VO_(4)solution.Firstly,a new V(V)speciation model for the aqueous solution containing vanadate and carbonate is established by using the Bromley-Zemaitis activity coefficient model.Subsequently,thermodynamic equilibrium calculations are conducted to clarify the behavior of vanadium,carbon,sodium,and impurity species in atmospheric or high-pressure carbonation.To ensure the purity and recovery of vanadium products,Na_(3)VO_(4)solution is initially carbonated to the pH of 9.3-9.4,followed by precipitating NH_(4)VO_(3)by adding(NH_(4))_(2)CO_(3).After vanadium precipitation,the solution is deeply carbonated to the final pH of 7.3-7.5 to precipitate NaHCO_(3),and the remaining solution is recycled to dissolve Na_(3)VO_(4)crystals.Finally,verification experiments demonstrate that 99.1%of vanadium and 91.4%of sodium in the solution are recovered in the form of NH_(4)VO_(3)and NaHCO_(3),respectively.
基金financially supported by the National Natural Science Foundation of China (Nos. 52174340, 51704338)the Basic Science Center of the National Natural Science Foundation of China (No. 72088101)the National Key Research and Development Project of China (No. 2022YFC2904505)。
