Electroactive species and method for electrochemical gas separation

A polymer or oligomer comprising repeating units derived from

• a first monomer comprising a polymerizable group and an electroactive species comprising a quinone core structure, and
• a second monomer comprising a polymerizable group and a stabilizing group comprising a cationic group, a hydrogen bond donor, or a combination thereof;
• wherein the electroactive species comprises
• an oxidized state, and
• at least one reduced state capable of bonding with a Lewis acid gas to form an anion adduct between the Lewis acid gas and the reduced electroactive species;
• and
• wherein the presence of the stabilizing group:
• kinetically favors the forming the anion adduct from the reduced electroactive species and the Lewis acid gas, or
• thermodynamically favors forming the anion adduct in a thermodynamic equilibrium between the anion adduct and the reduced electroactive species, or
• kinetically favors forming the anion adduct from the reduced electroactive species and thermodynamically favors the forming of the anion adduct in the thermodynamic equilibrium between the anion adduct and the reduced electroactive species.

An electrochemical apparatus comprising:

• a chamber comprising a negative electrode in electronic communication with an electroactive species in a reduced state, and an electrolyte, wherein the chamber is configured to receive a fluid mixture comprising a Lewis acid gas,
• wherein the electroactive species comprises a quinone core and at least one stabilizing group covalently bound thereto;
• wherein the stabilizing group comprises a cationic group, a hydrogen bond donor, or a combination thereof;
• and
• wherein the electroactive species comprises
• an oxidized state, and
• at least one reduced state capable of bonding with a Lewis acid gas to form an anion adduct between the Lewis acid gas and the reduced electroactive species;
• and
• wherein the presence of the stabilizing group:
• kinetically favors the forming the anion adduct from the reduced electroactive species and the Lewis acid gas, or
• thermodynamically favors forming the anion adduct in a thermodynamic equilibrium between the anion adduct and the reduced electroactive species, or
• kinetically favors forming the anion adduct from the reduced electroactive species and thermodynamically favors the forming of the anion adduct in the thermodynamic equilibrium between the anion adduct and the reduced electroactive species.

A gas separation system, comprising a plurality of electrochemical cells in fluid communication with a gas inlet and a gas outlet, wherein each of the plurality of electrochemical cells comprises:

• a first electrode comprising an electroactive species in a reduced state wherein the electroactive species comprises an oxidized state and at least one reduced state which bonds with a Lewis acid gas to form an anion adduct;
• a second electrode comprising a complementary electroactive layer;
• a first separator between the first electrode and the second electrode;
• and
• an electrolyte;
• wherein the electroactive species comprises a quinone core and at least one stabilizing group covalently bound thereto;
• wherein the stabilizing group comprises a cationic group, a hydrogen bond donor, or a combination thereof;
• and
• wherein the presence of the stabilizing group:
• kinetically favors the forming the anion adduct from the reduced electroactive species and the Lewis acid gas, or
• thermodynamically favors forming the anion adduct in a thermodynamic equilibrium between the anion adduct and the reduced electroactive species, or
• kinetically favors forming the anion adduct from the reduced electroactive species and thermodynamically favors the forming of the anion adduct in the thermodynamic equilibrium between the anion adduct and the reduced electroactive species.