Preparation method and application of superfine calcium hexaboride

A technology of fine calcium hexaboride and calcium borate, which is applied in the field of preparation of ultrafine calcium hexaboride, can solve problems such as no reports of calcium boride, and achieve the effect of not being easy to sinter

Inactive Publication Date: 2011-11-16
WUHAN UNIV
View PDF6 Cites 7 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Zhai et al reported a CaCl at 750 °C 2 -NaCl mixed salt, add B 2 o 3 Mixed sintered powder with CaO, graphite rods are used for cathode and anode, and calcium hexaboride crystals are produced by constant cell piezoelectric electrolysis, but the CaB produced by this method 6 The yield of the product is only 25%, and the particles of the product are mainly micron-sized
[0004] At present, calcium hexaboride is mainly used as a metal deoxidizer and as a raw material for preparing transition metal borides, and there is no report on calcium boride as a battery negative electrode.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Preparation method and application of superfine calcium hexaboride
  • Preparation method and application of superfine calcium hexaboride
  • Preparation method and application of superfine calcium hexaboride

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0026] Heat CaO, boric acid and water in a water bath at 100°C for 2 hours, then filter to obtain white precipitated calcium borate powder, then press the obtained calcium borate powder into a solid porous test piece, sinter at 400-500°C for 2 hours to shape, The porous calcium borate test piece is placed in a stainless steel basket as the cathode, graphite as the anode, and CaCl at 500-600°C 2 -Electrolyze in LiCl electrolyte for 20 hours under 2.6-3.6V tank pressure, wash off the salt and impurities in the product with water and dilute hydrochloric acid, and dry to obtain an ultrafine calcium hexaboride powder with a yellow appearance and a particle size of about 50nm ( figure 1 , 2 shows the obtained SEM and TEM pictures). After continuous electrolysis for 60 hours, put borax into the molten salt electrolyte and stir the electrolyte, and restart electrolysis after standing still. After repeating this many times, stop the electrolysis, dissolve the upper layer of calcium ch...

Embodiment 2

[0028] Ca(OH) 2 , borax and water were ball milled at room temperature for 2 hours, the product after ball milling was washed with water, filtered and dried to obtain a white powder, and the white powder was pressed into a porous test piece on a tablet machine, and then put into a muffle furnace at 650°C Calcined for 3 hours, the burnt calcium borate test piece was connected to the molybdenum wire as the cathode, tin dioxide as the anode at 600-690°C CaCl 2 -NaCl electrolyte with 2.8-3.8V cell piezo electrolysis for 12 hours, washing off the salt and impurities in the cathode product with water and dilute hydrochloric acid to obtain ultrafine calcium hexaboride with a particle size between 100nm and 1μm.

Embodiment 3

[0030] CaCl 2 , sodium borate and water were heated and reacted in a water bath at 100°C for 2 hours, and then filtered to obtain white precipitated calcium borate powder. Calcium borate and molybdenum mesh composite as solid cathode, graphite as anode, CaCl at 700-750°C under 2.4V-3.6V cell pressure 2 -Electrolyze in NaCl molten salt for 10 hours, remove the salt and a small amount of impurities from the product obtained at the cathode with water and dilute hydrochloric acid, and obtain CaB with a particle size of 1-5 μm 6 powder.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
particle sizeaaaaaaaaaa
particle sizeaaaaaaaaaa
Login to view more

Abstract

The invention discloses a preparation method and application of superfine calcium hexaboride to a battery. The preparation method comprises the steps of: carrying out electrolysis in a fused-salt electrolytic cell at a temperature of 500-750 DEG C through taking a composition of porous calcium borate and a metal current collector as the cathode and taking an insoluble conductor material as the anode, wherein fused-salt electrolyte contains a haloid corresponding to a metal capable of chemically reducing the calcium borate, and the voltage applied through the electrolysis is enough to reduce the calcium borate but not enough to resolve the fused-salt electrolyte; and taking out a reduction product on the cathode from the electrolytic cell, washing by using water and acid removing impurities, drying and then obtaining CaB6 powder. The obtained superfine calcium hexaboride can be used for a cathode material of a high-specific energy alkaline cell. By means of the method, the defects of high synthesis temperature, low yield and more expensive raw material of conventional boride are overcome and continuous production can be carried out.

Description

technical field [0001] The invention relates to a preparation method and application of ultrafine calcium hexaboride, belonging to the field of electrochemistry. Background technique [0002] Currently, CaB 6 The preparation of the powder is mainly synthesized by high temperature reaction, the boron source is mainly boron carbide, diboron trioxide and elemental boron, and the calcium source is mainly metallic calcium, calcium oxide and calcium carbonate. Traditional CaB 6 The synthesis methods are as follows: elemental boron and calcium are reacted in a closed tantalum crucible at 1000°C; calcium carbonate (CaCO 3 ) and boron carbide (B 4 C) At 1400°C, 10 -2 Carbothermal reduction under the condition of Pa; calcium oxide (CaO) and boron (B) are synthesized in vacuum at 1200-1800°C; sodium borohydride (NaBH 4 ) and calcium chloride (CaCl 2 ) were synthesized under high pressure, etc. In these preparation methods, there are problems such as relatively expensive raw mate...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C25B1/00C01B35/04
Inventor 汪的华尹华意朱华汤迪勇
Owner WUHAN UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap