We report the lithium ionic conductivities of closo –type complex hydrides synthesized from various molar ratios of lithium borohydride(LiBH4) and decaborane(B10H14) as starting materials. The prepared closo –type c...We report the lithium ionic conductivities of closo –type complex hydrides synthesized from various molar ratios of lithium borohydride(LiBH4) and decaborane(B10H14) as starting materials. The prepared closo –type complex hydrides comprised [B12H12]^2-, [B11H11]^2-, and [B10H10]^2- complex anions. In addition, increasing the LiBH4 content in the starting materials increased the amounts of [B11H11]^2- and [B10H10]^2-, leading to an improved ion conductivity of the prepared sample. The present study offers useful insights into strategies for controlling the complex anion composition in emerging solid electrolytes of closo-type complex hydrides at the molecular level, and improving their ionic conductivities.展开更多
We report on an all-solid-state battery that employs a closo-type complex hydride solid electrolyte and a LiCoO2 cathode.Interfacial modification between the solid electrolyte and cathode with a LiNbO3 buffer layer en...We report on an all-solid-state battery that employs a closo-type complex hydride solid electrolyte and a LiCoO2 cathode.Interfacial modification between the solid electrolyte and cathode with a LiNbO3 buffer layer enables reversible charge-discharge cycling with a cell voltage of 3.9V (vs.Li^+/Li) at room temperature.Electrochemical analyses clarify that the given modification effectively suppresses side reactions at the cathode/solid electrolyte interface.The interfacial resistance is lowered by ca.10 times with a 5 nm thick LiNbO3 buffer layer compared to that without a buffer layer,so that a discharge capacity of 109 mAh g^-1 is achieved.These results suggest that interfacial modification can be a viable approach to the development of high-voltage all-solid-state batteries using closo-type complex hydride solid electrolytes and oxide cathodes.展开更多
Complex aluminum hydrides have been widely studied as potential hydrogen storage materials but also,for some time now, for electrochemical applications. This review summarizes the crystal structures of alkali and alka...Complex aluminum hydrides have been widely studied as potential hydrogen storage materials but also,for some time now, for electrochemical applications. This review summarizes the crystal structures of alkali and alkaline earth aluminum hydrides and correlates structure properties with physical and chemical properties of the hydride compounds. The crystal structures of the alkali metal aluminum hydrides change significantly during the stepwise dehydrogenation. The general pathway follows a transformation of structures built of isolated [AlH4]- tetrahedra to structures built of isolated [Al H6]3- octahedra.The crystal structure relations in the group of alkaline earth metal aluminum hydrides are much more complicated than those of the alkali metal aluminum hydrides. The structures of the alkaline earth metal aluminum hydrides consist of isolated tetrahedra but the intermediate structures exhibit chains of cornershared octahedra. The coordination numbers within the alkali metal group increase with cation sizes which goes along with an increase of the decomposition temperatures of the primary hydrides. Alkaline earth metal hydrides have higher coordination numbers but decompose at slightly lower temperatures than their alkali metal counterparts. The decomposition pathways of alkaline metal aluminum hydrides have not been studied in all cases and require future research.展开更多
Here,we study the hydride formation in a metastable Ti-33Zr-22Hf-11Ta(at.%)refractory high entropy alloy(RHEA).Deviating to non-equiatomic compositions of RHEAs promotes the formation of transformation-induced plastic...Here,we study the hydride formation in a metastable Ti-33Zr-22Hf-11Ta(at.%)refractory high entropy alloy(RHEA).Deviating to non-equiatomic compositions of RHEAs promotes the formation of transformation-induced plasticity where the body-centered cubic phase transforms to hexagonal close-packed(HCP)phase.It is found that the phase transformation capability assists the hydride formation due to the low solubility of hydrogen within the HCP phase.In this study,hydrogen is charged via electrochemical polishing and the corresponding phase transformation is activated in the metastable RHEAs.The newly formed HCP phase interacts with hydrogen to form a face-centered cubic hydride verified by electron energy loss spectroscopy.This work provides a primary exploration of the formation of compositionally complex metal hydrides in the metastable RHEAs,which are potential candidates for future hydrogen storage material design.展开更多
We have reported that Cp<sub>3</sub>Ln/NaH （Cp=cyclopentadienyl） systems can reduce alkene s and catalyze the isomerization of olefins, and their reactivity depends on the radii of trivalent rare earth i...We have reported that Cp<sub>3</sub>Ln/NaH （Cp=cyclopentadienyl） systems can reduce alkene s and catalyze the isomerization of olefins, and their reactivity depends on the radii of trivalent rare earth ions; σ ligands in （C<sub>5</sub>H<sub>4</sub>CH<sub>2</sub>CH<sub>2</sub>CH<sub>2</sub>C<sub>5</sub>H<sub>4</sub>） LnX·THF/NaH systems also affect obviously the reducing activity of the systems. Herein, we wish to report the results of reduction of alkenes with L<sub>2</sub>YCl（THF）<sub>n</sub>/NaH (L:展开更多
Treatment of Ru(CO)(Cl)(H)(PPh3)3 with NaLOEt (LOEt-= [CpCo{P(O)(OEt)2}3]-) afforded the hydride complex (PPh3)(CO)-LOEtRu(H) (1), which has been characterized by X-ray crystallography. Similarly, the tricyclohexylpho...Treatment of Ru(CO)(Cl)(H)(PPh3)3 with NaLOEt (LOEt-= [CpCo{P(O)(OEt)2}3]-) afforded the hydride complex (PPh3)(CO)-LOEtRu(H) (1), which has been characterized by X-ray crystallography. Similarly, the tricyclohexylphosphine analogue, (PCy3)(CO)LOEtRu(H) (2), was synthesized from Ru(CO)Cl(H)(PCy3)2 and NaLOEt. Treatment of complex 1 with R'SO2N3 afforded the (arylsulfonyl)amido complexes LOEtRu(CO)(PPh3)(NHSO2R) (R = 2,4,6-i-Pr3C6H2 (3), 4-t-BuC6H4 (4)). The crystal structure of complex 3 has been determined. The Ru-N distance and Ru-N-S angle in 3 are 2.076(3) and 126.14(16)°, respectively. Reactions of complex 1 with acids have been studied.展开更多
In the early 1980’s, Schumann succeeded for the first time in the synthesis of the organolanthanide hydride complexes. Because the organolanthanide hydride complexes have very high catalytic activity and potential ap...In the early 1980’s, Schumann succeeded for the first time in the synthesis of the organolanthanide hydride complexes. Because the organolanthanide hydride complexes have very high catalytic activity and potential application, they have become a research focus.展开更多
In this paper,the microstructure and hydrogen storage properties of the（NaH/Al）+x（molar fraction,%） Ti（x=0,4,6, 10） composites were investigated.It was found that the reversible hydrogen storage properties can b...In this paper,the microstructure and hydrogen storage properties of the（NaH/Al）+x（molar fraction,%） Ti（x=0,4,6, 10） composites were investigated.It was found that the reversible hydrogen storage properties can be improved by mechanically ball-milling the（NaH/Al） mixture together with Ti powder.H2 is a better ball-milling atmosphere than Ar,because a part of NaH is consumed during the ball-milling under an Ar atmosphere.As the Ti content increases,the hydrogen storage properties are enhanced gradually.In case of x=10,the reversible hydrogen absorption/desorption capacities of the composites milled for 6 h under the H2 atmosphere reach 4.01% and 3.93%（mass fraction）,respectively.The catalytic mechanism of the Ti-doped NaH/Al composites system is discussed briefly.展开更多
基金supported by METX,JSPS KAKENHI (Grant numbers, 16K0 676 6, 17H0 6519, 17K18972, 18H01727, and JP18H05513)Collaborative Research Center on Energy Materials in IMR (E-IMR)Target Project 4 of WPI-AIMR, Tohoku University
文摘We report the lithium ionic conductivities of closo –type complex hydrides synthesized from various molar ratios of lithium borohydride(LiBH4) and decaborane(B10H14) as starting materials. The prepared closo –type complex hydrides comprised [B12H12]^2-, [B11H11]^2-, and [B10H10]^2- complex anions. In addition, increasing the LiBH4 content in the starting materials increased the amounts of [B11H11]^2- and [B10H10]^2-, leading to an improved ion conductivity of the prepared sample. The present study offers useful insights into strategies for controlling the complex anion composition in emerging solid electrolytes of closo-type complex hydrides at the molecular level, and improving their ionic conductivities.
基金supported by JSPS KAKENHI(Grant-in-Aid for Research Activity Start-up 17H06519)Grant-in-Aid for Early-Career Scientists(19K15666)+2 种基金Grant-in-Aid for Scientific Research on Innovative Areas“Hydrogenomics”(JP18H05513)the Collaborative Research Center on Energy Materials in IMR(E-IMR)Advanced Target Project-4 of WPI-AIMR,Tohoku University。
文摘We report on an all-solid-state battery that employs a closo-type complex hydride solid electrolyte and a LiCoO2 cathode.Interfacial modification between the solid electrolyte and cathode with a LiNbO3 buffer layer enables reversible charge-discharge cycling with a cell voltage of 3.9V (vs.Li^+/Li) at room temperature.Electrochemical analyses clarify that the given modification effectively suppresses side reactions at the cathode/solid electrolyte interface.The interfacial resistance is lowered by ca.10 times with a 5 nm thick LiNbO3 buffer layer compared to that without a buffer layer,so that a discharge capacity of 109 mAh g^-1 is achieved.These results suggest that interfacial modification can be a viable approach to the development of high-voltage all-solid-state batteries using closo-type complex hydride solid electrolytes and oxide cathodes.
文摘Complex aluminum hydrides have been widely studied as potential hydrogen storage materials but also,for some time now, for electrochemical applications. This review summarizes the crystal structures of alkali and alkaline earth aluminum hydrides and correlates structure properties with physical and chemical properties of the hydride compounds. The crystal structures of the alkali metal aluminum hydrides change significantly during the stepwise dehydrogenation. The general pathway follows a transformation of structures built of isolated [AlH4]- tetrahedra to structures built of isolated [Al H6]3- octahedra.The crystal structure relations in the group of alkaline earth metal aluminum hydrides are much more complicated than those of the alkali metal aluminum hydrides. The structures of the alkaline earth metal aluminum hydrides consist of isolated tetrahedra but the intermediate structures exhibit chains of cornershared octahedra. The coordination numbers within the alkali metal group increase with cation sizes which goes along with an increase of the decomposition temperatures of the primary hydrides. Alkaline earth metal hydrides have higher coordination numbers but decompose at slightly lower temperatures than their alkali metal counterparts. The decomposition pathways of alkaline metal aluminum hydrides have not been studied in all cases and require future research.
基金W.J.Lu is grateful for financial support from the open research fund of Songshan Lake Materials Laboratory(No.2021SLABFK05)the Shenzhen Science and Technology Program(No.JCYJ20210324104404012).
文摘Here,we study the hydride formation in a metastable Ti-33Zr-22Hf-11Ta(at.%)refractory high entropy alloy(RHEA).Deviating to non-equiatomic compositions of RHEAs promotes the formation of transformation-induced plasticity where the body-centered cubic phase transforms to hexagonal close-packed(HCP)phase.It is found that the phase transformation capability assists the hydride formation due to the low solubility of hydrogen within the HCP phase.In this study,hydrogen is charged via electrochemical polishing and the corresponding phase transformation is activated in the metastable RHEAs.The newly formed HCP phase interacts with hydrogen to form a face-centered cubic hydride verified by electron energy loss spectroscopy.This work provides a primary exploration of the formation of compositionally complex metal hydrides in the metastable RHEAs,which are potential candidates for future hydrogen storage material design.
基金Project supported by the National Natural Science Foundation of China
文摘We have reported that Cp<sub>3</sub>Ln/NaH （Cp=cyclopentadienyl） systems can reduce alkene s and catalyze the isomerization of olefins, and their reactivity depends on the radii of trivalent rare earth ions; σ ligands in （C<sub>5</sub>H<sub>4</sub>CH<sub>2</sub>CH<sub>2</sub>CH<sub>2</sub>C<sub>5</sub>H<sub>4</sub>） LnX·THF/NaH systems also affect obviously the reducing activity of the systems. Herein, we wish to report the results of reduction of alkenes with L<sub>2</sub>YCl（THF）<sub>n</sub>/NaH (L:
基金supported by the Hong Kong Research Grants Council (602209)
文摘Treatment of Ru(CO)(Cl)(H)(PPh3)3 with NaLOEt (LOEt-= [CpCo{P(O)(OEt)2}3]-) afforded the hydride complex (PPh3)(CO)-LOEtRu(H) (1), which has been characterized by X-ray crystallography. Similarly, the tricyclohexylphosphine analogue, (PCy3)(CO)LOEtRu(H) (2), was synthesized from Ru(CO)Cl(H)(PCy3)2 and NaLOEt. Treatment of complex 1 with R'SO2N3 afforded the (arylsulfonyl)amido complexes LOEtRu(CO)(PPh3)(NHSO2R) (R = 2,4,6-i-Pr3C6H2 (3), 4-t-BuC6H4 (4)). The crystal structure of complex 3 has been determined. The Ru-N distance and Ru-N-S angle in 3 are 2.076(3) and 126.14(16)°, respectively. Reactions of complex 1 with acids have been studied.
文摘In the early 1980’s, Schumann succeeded for the first time in the synthesis of the organolanthanide hydride complexes. Because the organolanthanide hydride complexes have very high catalytic activity and potential application, they have become a research focus.
基金Project (2010CB631300) supported by the National Basic Research Program of China Project (50631020) supported by the National Natural Science Foundation of China+1 种基金 Project (NCET-07-0741) supported by the Program for New Century Excellent Talents in Universities, ChinaProject (20090101110050) supported by the University Doctoral Foundation of the Ministry of Education, China
文摘In this paper,the microstructure and hydrogen storage properties of the（NaH/Al）+x（molar fraction,%） Ti（x=0,4,6, 10） composites were investigated.It was found that the reversible hydrogen storage properties can be improved by mechanically ball-milling the（NaH/Al） mixture together with Ti powder.H2 is a better ball-milling atmosphere than Ar,because a part of NaH is consumed during the ball-milling under an Ar atmosphere.As the Ti content increases,the hydrogen storage properties are enhanced gradually.In case of x=10,the reversible hydrogen absorption/desorption capacities of the composites milled for 6 h under the H2 atmosphere reach 4.01% and 3.93%（mass fraction）,respectively.The catalytic mechanism of the Ti-doped NaH/Al composites system is discussed briefly.
