V_(2)O_(5)·nH_(2)O has been widely studied for aqueous zinc-ion batteries.The intercalation of inorganic ions has been used as a feasible method to improve the capacity of vanadium pentoxide.To further improve th...V_(2)O_(5)·nH_(2)O has been widely studied for aqueous zinc-ion batteries.The intercalation of inorganic ions has been used as a feasible method to improve the capacity of vanadium pentoxide.To further improve the stability,organic small molecule choline chloride intercalation is used to expand the spacing of the vanadium pentoxide layers and increase the cycling stability.Therefore,we consider the introduction of Sr^(2+)to cointercalate with choline chloride.Here,we synthes-ized vanadium pentoxide cointercalated with Sr^(2+)and choline ions(Ch^(+))via a simple hydrothermal method.The electro-chemical performance shows an enhanced cathode capacitance contribution of Sr&Ch-V_(2)O_(5),with a discharge capacity of 526 mAh·g^(-1)at 0.1 A·g^(-1)and a retention rate of 78.9%after 2000 cycles at 5 A·g^(-1).This work offers a novel strategy for the design of organic‒inorganic hybrid materials for use as cathodes in aqueous zinc-ion batteries.展开更多
The acid bio-leaching process of vanadium extraction from clay vanadium water-leached residue was studied and the effect of the performance of iron transformation was investigated.Acidithiobacillus ferrooxidans affect...The acid bio-leaching process of vanadium extraction from clay vanadium water-leached residue was studied and the effect of the performance of iron transformation was investigated.Acidithiobacillus ferrooxidans affects the dissolution of vanadium through the catalytic effect on Fe^3+/Fe^2+couple and material exchange.The passivation of iron settling correlates with ferrous ion content in bio-leaching solution.In medium containing A.ferrooxidans and Fe(Ⅲ),the increment in Fe(Ⅱ)concentration leads to the formation of jarosite,generating a decline in vanadium extraction efficiency.Analysis of cyclic voltammetry shows that Fe(Ⅱ)ion is apt to be oxidized and translated into precipitate by A.ferrooxidans,which strongly adsorbed to the surface of the residue.Fe(Ⅲ)ion promotes the vanadium extraction due to its oxidizing activity.Admixing A.ferrooxidans to Fe(Ⅲ)medium elevates the reduction of low valence state vanadium and facilitates the exchange of substance between minerals and solution.This motivates 3.8%and 21.8%increments in recovery ratio and leaching rate of vanadium compared to the Fe(Ⅲ)exclusive use,respectively.Moreover,Fe(Ⅱ)ion impacts vanadium extraction slightly in sterile medium but negatively influences vanadium leaching in the presence of bacteria.展开更多
The violet polycrystalline (NH4)5[(VO)6(CO3)4(OH)9]·10H2O(NVCO) was simply sy nthesized by solution reaction using V2O5, HCl, N2H4·2HCl and NH4HCO3 as the st arting materials. The results of TGA and DTA of N...The violet polycrystalline (NH4)5[(VO)6(CO3)4(OH)9]·10H2O(NVCO) was simply sy nthesized by solution reaction using V2O5, HCl, N2H4·2HCl and NH4HCO3 as the st arting materials. The results of TGA and DTA of NVCO under H2(99.999%) atmosphe re show that V2O3 forms at 620℃. The data of TG/DTG and DTA of NVCO under N2(99 .999%) atmosphere indicate that VO2 forms at 367℃and crystallizes at 390℃. In air atmosphere, the TG/DTG and DTA of NVCO show that V2O5 forms at 354℃, cryst allizes at 366℃and melts at 664℃. The three thermolysis processes of NVCO show that a large amount of H2O, CO2 and NH3 gases fast releases during the thermoly sis of NVCO, causing that the particles of the materials split and atomize stron gly, thus to obtain V2O3, VO2 and V2O5 nano-powders finally. According to the a bove of thermoanalytical results, V2O3, VO2 and V2O5 powders were prepared respe ctively under H2, N2 and oxygen in a tube furnace. Chemical analysis and XRD exp eriments of the powders identify that pure V2O3 is obtained at 800℃for 0.5h und er H2 atmosphere; crystalline VO2 is obtained at 480℃for 0.5h in N2; amorphous VO2 is obtained at 350℃for 20min under N2 atmosphere, this has been first repor ted to prepare amorphous VO2 powder so far; pure V2O5 is obtained at 400℃for 10 min under oxygen. From the micrographs of the powders, the particle size of the V2O3, the crystalline VO2 or the V2O5 powders is 35nm, 24nm or < 40nm, respectiv ely. Above-mentioned results prove that NVCO is a good precursor for preparatio n of pure V2O3, VO2 and V2O5 nano-powders under mild conditions.展开更多
文摘V_(2)O_(5)·nH_(2)O has been widely studied for aqueous zinc-ion batteries.The intercalation of inorganic ions has been used as a feasible method to improve the capacity of vanadium pentoxide.To further improve the stability,organic small molecule choline chloride intercalation is used to expand the spacing of the vanadium pentoxide layers and increase the cycling stability.Therefore,we consider the introduction of Sr^(2+)to cointercalate with choline chloride.Here,we synthes-ized vanadium pentoxide cointercalated with Sr^(2+)and choline ions(Ch^(+))via a simple hydrothermal method.The electro-chemical performance shows an enhanced cathode capacitance contribution of Sr&Ch-V_(2)O_(5),with a discharge capacity of 526 mAh·g^(-1)at 0.1 A·g^(-1)and a retention rate of 78.9%after 2000 cycles at 5 A·g^(-1).This work offers a novel strategy for the design of organic‒inorganic hybrid materials for use as cathodes in aqueous zinc-ion batteries.
基金Project(DY135-B2-15) supported by the China Ocean Mineral Resource R&D AssociationProject(2015ZX07205-003) supported by Major Science and Technology Program for Water Pollution Control and Treatment,ChinaProjects(21176242,21176026) supported by the National Natural Science Foundation of China
文摘The acid bio-leaching process of vanadium extraction from clay vanadium water-leached residue was studied and the effect of the performance of iron transformation was investigated.Acidithiobacillus ferrooxidans affects the dissolution of vanadium through the catalytic effect on Fe^3+/Fe^2+couple and material exchange.The passivation of iron settling correlates with ferrous ion content in bio-leaching solution.In medium containing A.ferrooxidans and Fe(Ⅲ),the increment in Fe(Ⅱ)concentration leads to the formation of jarosite,generating a decline in vanadium extraction efficiency.Analysis of cyclic voltammetry shows that Fe(Ⅱ)ion is apt to be oxidized and translated into precipitate by A.ferrooxidans,which strongly adsorbed to the surface of the residue.Fe(Ⅲ)ion promotes the vanadium extraction due to its oxidizing activity.Admixing A.ferrooxidans to Fe(Ⅲ)medium elevates the reduction of low valence state vanadium and facilitates the exchange of substance between minerals and solution.This motivates 3.8%and 21.8%increments in recovery ratio and leaching rate of vanadium compared to the Fe(Ⅲ)exclusive use,respectively.Moreover,Fe(Ⅱ)ion impacts vanadium extraction slightly in sterile medium but negatively influences vanadium leaching in the presence of bacteria.
文摘The violet polycrystalline (NH4)5[(VO)6(CO3)4(OH)9]·10H2O(NVCO) was simply sy nthesized by solution reaction using V2O5, HCl, N2H4·2HCl and NH4HCO3 as the st arting materials. The results of TGA and DTA of NVCO under H2(99.999%) atmosphe re show that V2O3 forms at 620℃. The data of TG/DTG and DTA of NVCO under N2(99 .999%) atmosphere indicate that VO2 forms at 367℃and crystallizes at 390℃. In air atmosphere, the TG/DTG and DTA of NVCO show that V2O5 forms at 354℃, cryst allizes at 366℃and melts at 664℃. The three thermolysis processes of NVCO show that a large amount of H2O, CO2 and NH3 gases fast releases during the thermoly sis of NVCO, causing that the particles of the materials split and atomize stron gly, thus to obtain V2O3, VO2 and V2O5 nano-powders finally. According to the a bove of thermoanalytical results, V2O3, VO2 and V2O5 powders were prepared respe ctively under H2, N2 and oxygen in a tube furnace. Chemical analysis and XRD exp eriments of the powders identify that pure V2O3 is obtained at 800℃for 0.5h und er H2 atmosphere; crystalline VO2 is obtained at 480℃for 0.5h in N2; amorphous VO2 is obtained at 350℃for 20min under N2 atmosphere, this has been first repor ted to prepare amorphous VO2 powder so far; pure V2O5 is obtained at 400℃for 10 min under oxygen. From the micrographs of the powders, the particle size of the V2O3, the crystalline VO2 or the V2O5 powders is 35nm, 24nm or < 40nm, respectiv ely. Above-mentioned results prove that NVCO is a good precursor for preparatio n of pure V2O3, VO2 and V2O5 nano-powders under mild conditions.
