Novel Sulphur-Modified Monolithic Porous Carbon-Based Material, Process For The Preparation Thereof And Uses Thereof In The Storage And Release Of Energy

Abstract

A subject-matter of the invention is a novel process for the preparation of sulphur-modified monolithic porous carbon-based materials by impregnation with a strong sulphur-based acid, the materials capable of being obtained according to this process and the use of these materials with improved supercapacitance properties to produce electrodes intended for energy storage systems. Electrodes composed of sulphur-modified monolithic porous carbon-based materials according to the invention and lithium batteries and supercapacitors having such electrodes also form part of the invention.

1 . A sulphur-modified monolithic porous carbon-based material obtained according to a process comprising at least the following stages:
 (i) drying of a gel comprising at least one hydrophilic polymer of polyhydroxybenzene/formaldehyde type,   (ii) pyrolysis of the material obtained during stage (i),   (iii) impregnation of the material resulting from stage (ii) with a strong sulphur-based acid,   (iv) heat treatment at a temperature of between 300 and 500° C., of the sulphur-modified material obtained at the end of stage (iii),   
       wherein said process does not comprise a hydrogenation stage, and wherein the material comprises a surface atomic percentage of sulphur varying from 0.01 to 0.5%, and exhibiting a density of between 0.5 and 1.3. 
     
     
         2 . The material according to  claim 1 , wherein the material comprises a surface atomic percentage of sulphur varying from 0.1 to 0.5%, and a density of between 0.75 and 1.1. 
     
     
         3 . The material according to  claim 1 , wherein the material exhibits a pore volume varying from 0.4 to 1 cm 3 ·g −1 . 
     
     
         4 . The material according to  claim 1 , wherein the material exhibits a pore volume varying from 0.4 to 0.75 cm 3 ·g −1 . 
     
     
         5 . The material according to  claim 1 , wherein at least 10% of pores of the material have a diameter of between 2 and 50 nm. 
     
     
         6 . The material according to  claim 1 , wherein the material exhibits a specific surface of greater than or equal to 500 m 2 ·g −1 . 
     
     
         7 . The material according to  claim 1 , wherein the material exhibits a mean full capacitance by weight of greater than or equal to 140 F/g, measured in a 1M aqueous H 2 SO 4  solution, or of greater than or equal to 120 F/g, measured in a 6M aqueous KOH solution. 
     
     
         8 . An electrode for a supercapacitance energy storage system, the electrode comprising the material of  claim 1 . 
     
     
         9 . An electrode comprising a sulphur-modified monolithic porous carbon-based material having a surface atomic percentage of sulphur varying from 0.01 to 0.5%, and exhibiting a density of between 0.5 and 1.3. 
     
     
         10 . A supercapacitor comprising at least one electrode according to  claim 9 . 
     
     
         11 . A lithium battery comprising at least one electrode according to  claim 9 . 
     
     
         12 . A sulphur modified carbon-based material comprising a carbon monolith and having a network of pores in which at least 10% of the pores have a diameter between 2 and 50 nm, and wherein the material comprises a surface atomic percentage of sulphur varying from 0.01 to 0.5%, a density of between 0.5 and 1.3, and a mean full capacitance by weight of greater than or equal to 140 F/g, measured in a 1M aqueous H 2 SO 4  solution, or of greater than or equal to 120 F/g, measured in a 6M aqueous KOH solution. 
     
     
         13 . The material of  claim 12 , wherein more than 20% of the pores have a diameter between 2 and 50 nm. 
     
     
         14 . The material of  claim 12 , wherein the material exhibits a specific surface of greater than or equal to 500 m 2 ·g −1 . 
     
     
         15 . The material of  claim 12 , wherein the material comprises a surface atomic percentage of sulphur varying from 0.1 to 0.5%, a density of between 0.75 and 1.1. 
     
     
         16 . The material according to  claim 15 , wherein the material exhibits a pore volume varying from 0.4 to 1 cm 3 ·g −1 . 
     
     
         17 . The material according to  claim 15 , wherein the material exhibits a pore volume varying from 0.4 to 0.75 cm 3 ·g −1 . 
     
     
         18 . The material of  claim 12 , wherein the material exhibits a surface concentration of oxygen ranging from 16 to 23% and a surface concentration of nitrogen ranging from 0 to 1%. 
     
     
         19 . An electrode comprising the material of  claim 12 . 
     
     
         20 . A supercapacitor comprising at least one electrode according to  claim 19 . 
     
     
         21 . A lithium battery comprising at least one electrode according to  claim 19 .