Activated carbon electrode material

A process for producing activated carbon particles of an activated carbon powder, the process comprising:

• conducting an activation-pyrolyzation treatment of a precursor that comprises a uncarbonized plant material powder, a partially carbonized plant material powder, or a combination thereof, wherein the activation-pyrolyzation treatment comprises:
• mixing the precursor with an activating agent to form a precursor-activating agent mixture, wherein the activating agent is selected to react with carbon in the precursor during the activation-pyrolyzation treatment thereby forming one or more products that are suitable to be removed during a washing treatment conducted after the activation-pyrolyzation treatment;
• and combinations thereof;
• and
• heating the precursor-activating agent mixture in a pyrolyzation inert atmosphere at a pyrolyzation temperature and for a pyrolyzation duration sufficient to complete the carbonization of the precursor thereby forming an activated-pyrolyzed material;
• and
• conducting a washing treatment of the activated-pyrolyzed material with one or more washing liquids suitable to reduce or remove the one or more products of the reaction between carbon and the activating agent from the activated-pyrolyzed material thereby forming the activated carbon particles of the activated carbon powder, wherein the activated carbon particles have a Brunauer-Emmett-Teller (BET) surface area that is in a range of about 900 m2/g to about 2,500 m2/g, and wherein the activated carbon particles comprise:
• (a) carbon that comprises:
• (i) D-band carbon corresponding to a sp3 hybridized disordered carbon phase;
• and
• (ii) G-band carbon corresponding to a sp2 hybridized graphitic phase;
• wherein the D-band carbon and G-band carbon are at a proportion, determined using Raman spectroscopy to arrive at relative intensities of D-band carbon (ID) and G-band carbon (IG), such that a IG/ID ratio is in a range of 0 to about 2;
• (b) nitrogen at an amount, determined by X-ray photoelectron spectroscopy, that is in a range of about 0.3 atomic % to about 1.8 atomic % of the activated carbon particles, wherein at least some of the nitrogen atoms are substituted for carbon atoms in the crystal lattice structure of the G-band carbon sp2 hybridized graphitic phase;
• and
• (c) mesopores with diameters in a range of 2 nm to 5 nm and micropores with diameters less than 2 nm, the activated carbon particles having:
• (i) an average pore width, determined by the Barrett, Joyner, and Halenda (BJH) method, in a range of about 1 nm to about 4 nm;
• (ii) a microporous surface area, determined by the t-plot method, in a range of about 300 m2/g to about 1,350 m2/g;
• and
• (iii) a cumulative surface area of micropores with a hydraulic radius in a range of 0.285 nm to 1.30 nm that is in a range of about 1,000 m2/g to about 3,000 m2/g.

An electrode comprising an activated carbon powder comprising activated carbon particles, wherein the activated carbon particles have a Brunauer-Emmett-Teller (BET) surface area that is in a range of about 900 m2/g to about 2,500 m2/g, and wherein the activated carbon particles comprise:

• (a) carbon that comprises:
• (i) D-band carbon corresponding to a sp3 hybridized disordered carbon phase;
• and
• (ii) G-band carbon corresponding to a sp2 hybridized graphitic phase;
• wherein the D-band carbon and G-band carbon are at a proportion, determined using Raman spectroscopy to arrive at relative intensities of D-band carbon (ID) and G-band carbon (IG), such that a IG/ID ratio is in a range of 0 to about 2;
• (b) nitrogen at an amount, determined by X-ray photoelectron spectroscopy, that is in a range of about 0.3 atomic % to about 1.8 atomic % of the activated carbon particles, wherein at least some of the nitrogen atoms are substituted for carbon atoms in the crystal lattice structure of the G-band carbon sp2 hybridized graphitic phase;
• and
• (c) mesopores with diameters in a range of 2 nm to 5 nm and micropores with diameters less than 2 nm, the activated carbon particles having:
• (i) an average pore width, determined by the Barrett, Joyner, and Halenda (BJH) method, in a range of about 1 nm to about 4 nm;
• (ii) a microporous surface area, determined by the t-plot method, in a range of about 300 m2/g to about 1,350 m2/g;
• and
• (ii) a cumulative surface area of micropores with a hydraulic radius in a range of 0.285 nm to 1.30 nm that is in a range of about 1,000 m2/g to about 3,000 m2/g.

A battery or supercapacitor comprising an electrode comprising an activated carbon powder comprising activated carbon particles, wherein the activated carbon particles have a Brunauer-Emmett-Teller (BET) surface area that is in a range of about 900 m2/g to about 2,500 m2/g, and wherein the activated carbon particles comprise:

• (a) carbon that comprises:
• (i) D-band carbon corresponding to a sp3 hybridized disordered carbon phase;
• and
• (ii) G-band carbon corresponding to a sp2 hybridized graphitic phase;
• wherein the D-band carbon and G-band carbon are at a proportion, determined using Raman spectroscopy to arrive at relative intensities of D-band carbon (ID) and G-band carbon (IG), such that a IG/ID ratio is in a range of 0 to about 2;
• (b) nitrogen at an amount, determined by X-ray photoelectron spectroscopy, that is in a range of about 0.3 atomic % to about 1.8 atomic % of the activated carbon particles, wherein at least some of the nitrogen atoms are substituted for carbon atoms in the crystal lattice structure of the G-band carbon sp2 hybridized graphitic phase;
• and
• (c) mesopores with diameters in a range of 2 nm to 5 nm and micropores with diameters less than 2 nm, the activated carbon particles having:
• (i) an average pore width, determined by the Barrett, Joyner, and Halenda (BJH) method, in a range of about 1 nm to about 4 nm;
• (ii) a microporous surface area, determined by the t-plot method, in a range of about 300 m2/g to about 1,350 m2/g;
• and
• (ii) a cumulative surface area of micropores with a hydraulic radius in a range of 0.285 nm to 1.30 nm that is in a range of about 1,000 m2/g to about 3,000 m2/g.