Method for preparing nitrogen-doped multi-dimensional hierarchical porous carbon material adaptive to sulfur positive electrode carrier of aluminum-sulfur battery

Abstract

The invention relates to a method for preparing a nitrogen-doped multi-dimensional hierarchical porous carbon material with high specific surface area and high pore volume. The nitrogen-doped multi-dimensional hierarchical porous carbon material is used as a sulfur positive electrode carrier adaptive to an aluminum-sulfur battery. The preparation method comprises the following specific steps: 1, preparing a polymer precursor with high nitrogen content through amine-aldehyde condensation polymerization; 2, carbonizing the precursor under the actions of high-temperature volatilization of zinc salt and the like to prepare a nitrogen-doped multi-dimensional hierarchical porous carbon material; 3, optimizing the pore channel structure of the nitrogen-doped three-dimensional hierarchical pore carbon material through potassium hydroxide etching; 4, loading elemental sulfur into the nitrogen-doped multi-dimensional hierarchical porous carbon through a sublimation method to form a composite positive electrode; 5, preparing a positive pole piece of the aluminum-sulfur battery; 6, performing battery assembly and performance evaluation. The discharge capacity of a battery assembled by the aluminum-sulfur battery positive electrode material prepared by the method and acetamide / aluminum chloride electrolyte is kept at 1000 mAh g <-1> or above after 50 cycles at 0.2 A g <-1>, and the discharge capacity is kept at 400 mAh g <-1> or above and the coulombic efficiency is kept at 96% or above after 700 cycles at 1A g <-1 >. The preparation method has the advantages of low raw material cost, environment friendliness, good structure optimization effect, easiness in modification, good cycle performance of the assembled aluminum-sulfur battery and the like. The method is applied to the field of aluminum-sulfur batteries.

Description

technical field [0001] The invention relates to a method for preparing a nitrogen-doped multi-dimensional and hierarchical porous carbon material suitable for the sulfur positive electrode carrier of an aluminum-sulfur battery, and specifically relates to the technical field of aluminum-sulfur batteries. Background technique [0002] After decades of rapid development, lithium ions have been widely used in electronic products, power energy, military and other fields. At present, the secondary battery market is still dominated by lithium-ion batteries. However, factors such as scarcity of resources, high cost, and potential safety hazards limit the future large-scale application prospects of lithium-ion batteries. [0003] Aluminum-ion batteries have the advantages of low price, high safety, and environmental protection. Among them, aluminum-sulfur batteries have attracted widespread attention because of their low price and ultra-high theoretical specific capacity. However,...

AI Technical Summary

Problems solved by technology

However, since the electrochemical reaction environment of aluminum-sulfur batteries is completely different from that of lithium-sulfur batteries, such as the low conductivity and high viscosity of ionic liquids, the electrolyte and positive electrodes are poorly infiltrated, which poses different requirements for the structural design of carbon supports. requirements

Images