TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: Carbon precursor comprises nitrogen-containing polymer and human and animal hair. Human and animal hair is human hair, pig hair, or dog hair. Preferred Processes: Preparation of recrystallized solid salt functional carbon material includes weighing 8 g aniline and 1 g salicylic acid, dissolving in 400 ml deionized water, stirring at room temperature for 24 hours to obtain aniline salicylate solution, weighing 16 g ammonium persulfate, dissolving in 100 ml deionized water to obtain ammonium persulfate aqueous solution, adding aniline salicylate solution and ammonium persulfate aqueous solution, stirring at 0.8 ml/minute for 48 hours, filtering, washing, ultrasonically dispersing residue in deionized water to obtain 5 g/ml polyaniline suspension, soaking for 6 hours, ultrasonically dispersing residue in ethanol to obtain 5 g/ml carbon precursor ethanol dispersion, soaking for 6 hours, washing with deionized water and ethanol, drying under vacuum state for 24 hours to obtain three-dimensional network polyaniline, weighing three-dimensional network polyaniline:iron salt:cobalt salt with mass ratio of 1:0-4:0-4, dissolving 60-250 g soluble salt crystal in 120-250 ml deionized water at 60-90 degrees C to obtain soluble salt supersaturated solution, dispersing three-dimensional network polyaniline in 5-15 ml deionized water, ultrasonically mixing for 1-3 hours to obtain 0.2-5 g/ml three-dimensional network polyaniline suspension, adding iron salt and cobalt salt in three-dimensional network polyaniline suspension, stirring for 12-36 hours to adsorb, adding 5-25 ml soluble salt supersaturated solution, stirring for 2-4 hours, evaporating solvent at 60-95 degrees C, slowly dropping 110-210 ml soluble salt supersaturated solution, crystallizing, adding water, evaporating to obtain 5-15 ml soluble salt supersaturated solution, placing in vacuum oven at - 0.05 MPa to - 0.1 MPa, crystallizing at 30-70 degrees C for 12-24 hours to obtain soluble salt crystal encapsulated three-dimensional network polyaniline, dehydrating at 110-160 degrees C for 1-5 hours under protection of nitrogen or argon atmosphere, performing pyrolysis at 800-1100 degrees C, cooling at room temperature to obtain soluble salt crystals encapsulated carbonized three-dimensional network polyaniline, dissolving in 0.1-1 mol/L acidic aqueous solution, stirring at 60-90 degrees C for 2-5 hours, filtering under vacuum state, washing with deionized water, washing with absolute ethanol, and drying at 60 degrees C for 24 hours. Preparation of recrystallized solid salt functional carbon material includes ultrasonically dispersing human hair in deionized water to obtain 5 g/ml human hair suspension, filtering, washing, ultrasonically dispersing residue in deionized water to obtain 5 g/ml human hair suspension, soaking for 6 hours, washing with deionized water and ethanol, drying under vacuum state for 24 hours to obtain human hair precursor, weighing human hair precursor:ferric chloride with mass ratio of 1:1, dissolving 60 g sodium chloride in 250 ml deionized water at 80 degrees C to obtain sodium chloride supersaturated solution, dispersing human hair precursor in 10 ml deionized water, ultrasonically mixing for 2 hours to obtain 3 g/ml human hair precursor suspension, adding ferric chloride in human hair precursor suspension, stirring for 24 hours to adsorb, adding 25 ml sodium chloride supersaturated solution, stirring for 3 hours, evaporating solvent at 80 degrees C, slowly dropping 115 ml sodium chloride supersaturated solution with rate of 1.5 ml/minute, crystallizing, adding water, evaporating to obtain 10 ml sodium chloride supersaturated solution, placing in vacuum oven at - 0.08 MPa, crystallizing at 60 degrees C for 12 hours to obtain sodium chloride encapsulated human hair precursor, dehydrating at 120 degrees C for 3 hours under protection of nitrogen or argon atmosphere, performing pyrolysis at 900 degrees C with rate of 6 degrees C/minute, cooling at room temperature to obtain sodium chloride encapsulated carbonized human hair precursor, dissolving in 0.5 mol/L acidic aqueous solution, stirring at 80 degrees C for 3 hours, filtering under vacuum state, washing with deionized water, washing with absolute ethanol, and drying at 60 degrees C for 24 hours.    TECHNOLOGY FOCUS - POLYMERS - Preferred Components: Nitrogen-containing polymer is polyaniline, pyrazol, or polydopamine.