Nickel boride/boron-doped porous carbon material and preparation thereof, and application in lithium-sulfur battery

Abstract

The invention belongs to the field of battery materials, and particularly relates to a nickel boride / boron-doped porous carbon material which is a porous carbon ball with a through hole structure andcomprises a plurality of template etching holes. A carbon skeleton of the porous carbon ball is boron-doped disordered carbon; nickel elementary substance particles coated with graphitized carbon areembedded in the carbon skeleton in situ; and nickel boride nanoparticles are embedded in a surface. The invention also provides a preparation method and an application of the material. Special components and the material with the special in-situ morphology can show excellent conductivity and polysulfide catalytic activity and can show an excellent capacity, rate and cycle performance when being used as a lithium-sulfur battery after being loaded with sulfur.

Description

technical field

[0001] The invention relates to the field of battery electrode material preparation, in particular to a lithium-sulfur battery cathode material. Background technique

[0002] Lithium-sulfur batteries have outstanding advantages such as high theoretical energy density and low cost, and have unique advantages in achieving the "long-term research goal of high specific energy and long-life power batteries". However, problems such as the insulation of elemental sulfur, the shuttle effect of soluble lithium polysulfide, the polarization effect of the sulfur electrode and the volume expansion and contraction effect lead to low sulfur utilization, limited power density and short cycle life of the battery have become its practical application. bottleneck. Although the theoretical energy density of lithium-sulfur batteries is high, there is a large gap between the actual value and the theoretical value, and the rate performance is limited and the cycle life is short. ...

Examples

Embodiment 1

[0076] 5 kg of tapioca starch, 5 kg of 100nm SiO 2 Add the template dispersion, 40 grams of nickel acetate and 50 grams of sodium dodecylsulfonate into 10L of deionized water, stir at 80°C for 5 hours, dry the slurry at 120°C, and pulverize the dried slurry Finally, carbonize in a carbonization furnace at 1200°C for three hours under an argon atmosphere; the carbonized product is washed off SiO with 5M sodium hydroxide solution at a temperature of 100°C 2 template; use deionized water to wash repeatedly until the pH of the washing solution is neutral, and dry in the air for three days to oxidize the nickel atoms on the surface of the carbon material, and then add a newly prepared sodium borohydride solution (concentration of 0.2M , the solid-to-liquid ratio is 1:10), after stirring and reacting for three hours, filter and dry to obtain a localized graphitized boron-doped porous carbon material with rich pore structure and in-situ growth of nickel boride particles on the surfac...

Embodiment 2

[0079] Compared with Example 1, the difference mainly lies in increasing the consumption of nickel source, specifically:

[0080] 5 kg of tapioca starch, 5 kg of 100nm SiO 2 Add the template dispersion, 400 grams of nickel acetate and 50 grams of sodium dodecylsulfonate into 10L of deionized water, stir at 80°C for 5 hours, dry the slurry at 120°C, and pulverize the dried slurry Finally, carbonize in a carbonization furnace at 1200°C for three hours under an argon atmosphere; the carbonized product is washed off SiO with 5M sodium hydroxide solution at a temperature of 100°C 2 template; use deionized water to wash repeatedly until the pH of the washing solution is neutral, and dry in the air for three days to oxidize the nickel atoms on the surface of the carbon material, and then add a newly prepared sodium borohydride solution (concentration of 0.2M , the solid-to-liquid ratio is 1:10), after stirring and reacting for three hours, filter and dry to obtain a localized graphi...

Embodiment 3

[0083] Compared with Example 1, the only difference is that the carbonization temperature is 800°C, specifically:

[0084] 5 kg of tapioca starch, 5 kg of 100nm SiO 2 Add the template dispersion, 40 grams of nickel acetate and 50 grams of sodium dodecylsulfonate into 10L of deionized water, stir at 80°C for 5 hours, dry the slurry at 120°C, and pulverize the dried slurry Finally, carbonize in a carbonization furnace at 800°C for three hours under an argon atmosphere; the carbonized product is washed off SiO with 5M sodium hydroxide solution at a temperature of 100°C. 2 template; use deionized water to wash repeatedly until the pH of the washing solution is neutral, and dry in the air for three days to oxidize the nickel atoms on the surface of the carbon material, and then add a newly prepared sodium borohydride solution (concentration of 0.2M , the solid-to-liquid ratio is 1:10), after stirring and reacting for three hours, filter and dry to obtain a localized graphitized bo...

technical field

[0001] The invention relates to the field of battery electrode material preparation, in particular to a lithium-sulfur battery cathode material. Background technique

[0002] Lithium-sulfur batteries have outstanding advantages such as high theoretical energy density and low cost, and have unique advantages in achieving the "long-term research goal of high specific energy and long-life power batteries". However, problems such as the insulation of elemental sulfur, the shuttle effect of soluble lithium polysulfide, the polarization effect of the sulfur electrode and the volume expansion and contraction effect lead to low sulfur utilization, limited power density and short cycle life of the battery have become its practical application. bottleneck. Although the theoretical energy density of lithium-sulfur batteries is high, there is a large gap between the actual value and the theoretical value, and the rate performance is limited and the cycle life is short. ...

Examples

Embodiment 1

[0076] 5 kg of tapioca starch, 5 kg of 100nm SiO 2 Add the template dispersion, 40 grams of nickel acetate and 50 grams of sodium dodecylsulfonate into 10L of deionized water, stir at 80°C for 5 hours, dry the slurry at 120°C, and pulverize the dried slurry Finally, carbonize in a carbonization furnace at 1200°C for three hours under an argon atmosphere; the carbonized product is washed off SiO with 5M sodium hydroxide solution at a temperature of 100°C 2 template; use deionized water to wash repeatedly until the pH of the washing solution is neutral, and dry in the air for three days to oxidize the nickel atoms on the surface of the carbon material, and then add a newly prepared sodium borohydride solution (concentration of 0.2M , the solid-to-liquid ratio is 1:10), after stirring and reacting for three hours, filter and dry to obtain a localized graphitized boron-doped porous carbon material with rich pore structure and in-situ growth of nickel boride particles on the surfac...

Embodiment 2

[0079] Compared with Example 1, the difference mainly lies in increasing the consumption of nickel source, specifically:

[0080] 5 kg of tapioca starch, 5 kg of 100nm SiO 2 Add the template dispersion, 400 grams of nickel acetate and 50 grams of sodium dodecylsulfonate into 10L of deionized water, stir at 80°C for 5 hours, dry the slurry at 120°C, and pulverize the dried slurry Finally, carbonize in a carbonization furnace at 1200°C for three hours under an argon atmosphere; the carbonized product is washed off SiO with 5M sodium hydroxide solution at a temperature of 100°C 2 template; use deionized water to wash repeatedly until the pH of the washing solution is neutral, and dry in the air for three days to oxidize the nickel atoms on the surface of the carbon material, and then add a newly prepared sodium borohydride solution (concentration of 0.2M , the solid-to-liquid ratio is 1:10), after stirring and reacting for three hours, filter and dry to obtain a localized graphi...

Embodiment 3

[0083] Compared with Example 1, the only difference is that the carbonization temperature is 800°C, specifically:

[0084] 5 kg of tapioca starch, 5 kg of 100nm SiO 2 Add the template dispersion, 40 grams of nickel acetate and 50 grams of sodium dodecylsulfonate into 10L of deionized water, stir at 80°C for 5 hours, dry the slurry at 120°C, and pulverize the dried slurry Finally, carbonize in a carbonization furnace at 800°C for three hours under an argon atmosphere; the carbonized product is washed off SiO with 5M sodium hydroxide solution at a temperature of 100°C. 2 template; use deionized water to wash repeatedly until the pH of the washing solution is neutral, and dry in the air for three days to oxidize the nickel atoms on the surface of the carbon material, and then add a newly prepared sodium borohydride solution (concentration of 0.2M , the solid-to-liquid ratio is 1:10), after stirring and reacting for three hours, filter and dry to obtain a localized graphitized bo...

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