The new mixed borates with formula(Rb 2 Ca [B 4 O 5 (OH) 4 ] 2 ·8H 2 O and Cs 2 Ca [B 4 O 5 (OH) 4 ] 2 ·8H 2 O)were prepared by reaction Rb (Cs )-borate aqueous solution with CaCl 2 .Two kinds of compounds w...The new mixed borates with formula(Rb 2 Ca [B 4 O 5 (OH) 4 ] 2 ·8H 2 O and Cs 2 Ca [B 4 O 5 (OH) 4 ] 2 ·8H 2 O)were prepared by reaction Rb (Cs )-borate aqueous solution with CaCl 2 .Two kinds of compounds were characterized by chemical analysis,X-ray powder dif fraction,FT-IR spectra and thermal analysis.展开更多
The anode material Zn4SO4（OH）6·5H2O for nickle/zinc batteries was synthesized by hydrothermal method and was identified by XRD techniques. TG/DAT measurements reveal that the products lose lattice water at 145 ...The anode material Zn4SO4（OH）6·5H2O for nickle/zinc batteries was synthesized by hydrothermal method and was identified by XRD techniques. TG/DAT measurements reveal that the products lose lattice water at 145 ℃ and decompose to 3ZnO·ZnSO4 at 274 ℃. Cyclic voltammetry and recharging/discharging results show that CV curves have good symmetry, the ratio of oxidation area to reduction area for each curve is about 1, and the peak potential EPa and EPc have little change with the scanning rate. At 50th circle, more than 65% of theoretical capacity is obtained while at the same condition, zinc oxide electrode only remains 35% of theoretical capacity.展开更多
ZrW2O7(OH,Cl)2·2H2O and its isomorphs were prepared by Acidic Steam Hydrothermal (ASH) method and the pure cubic ZrW2O8 was synthesized by dehydration of ZrW2O7(OH,Cl)2·2H2O. The control factors of ASH metho...ZrW2O7(OH,Cl)2·2H2O and its isomorphs were prepared by Acidic Steam Hydrothermal (ASH) method and the pure cubic ZrW2O8 was synthesized by dehydration of ZrW2O7(OH,Cl)2·2H2O. The control factors of ASH method, such as the type, concentration and volume of the acidic steam source, temperature and time of the reac- tion, were studied in detail. The results showed that HCl was a better volatile acidic steam source and the con- centration of HCl determined the product. At lower concentration of HCl, the main product was Na2W2O7·H2O rather than ZrW2O7(OH,Cl)2·2H2O. When the concentration was higher than 6 mol·L-1, the products in turn be- came sodium tungstates with the structure types of pyrochlore, hexagonal tungsten bronze and finally were trans- formed to ZrW2O7(OH,Cl)·22H2O precursors.展开更多
文摘The new mixed borates with formula(Rb 2 Ca [B 4 O 5 (OH) 4 ] 2 ·8H 2 O and Cs 2 Ca [B 4 O 5 (OH) 4 ] 2 ·8H 2 O)were prepared by reaction Rb (Cs )-borate aqueous solution with CaCl 2 .Two kinds of compounds were characterized by chemical analysis,X-ray powder dif fraction,FT-IR spectra and thermal analysis.
文摘The anode material Zn4SO4（OH）6·5H2O for nickle/zinc batteries was synthesized by hydrothermal method and was identified by XRD techniques. TG/DAT measurements reveal that the products lose lattice water at 145 ℃ and decompose to 3ZnO·ZnSO4 at 274 ℃. Cyclic voltammetry and recharging/discharging results show that CV curves have good symmetry, the ratio of oxidation area to reduction area for each curve is about 1, and the peak potential EPa and EPc have little change with the scanning rate. At 50th circle, more than 65% of theoretical capacity is obtained while at the same condition, zinc oxide electrode only remains 35% of theoretical capacity.
文摘ZrW2O7(OH,Cl)2·2H2O and its isomorphs were prepared by Acidic Steam Hydrothermal (ASH) method and the pure cubic ZrW2O8 was synthesized by dehydration of ZrW2O7(OH,Cl)2·2H2O. The control factors of ASH method, such as the type, concentration and volume of the acidic steam source, temperature and time of the reac- tion, were studied in detail. The results showed that HCl was a better volatile acidic steam source and the con- centration of HCl determined the product. At lower concentration of HCl, the main product was Na2W2O7·H2O rather than ZrW2O7(OH,Cl)2·2H2O. When the concentration was higher than 6 mol·L-1, the products in turn be- came sodium tungstates with the structure types of pyrochlore, hexagonal tungsten bronze and finally were trans- formed to ZrW2O7(OH,Cl)·22H2O precursors.
