Ultrafast, high-energy supercapacitors with open-shell polymer-carbon-based compound composites
Embodiments of the presently disclosed technology provide a synergistic combination of a conjugated open-shell donor-acceptor polymer with a carbon-based compound (e.g., reduced graphene oxide) to produce a composite electrode material which demonstrates state-of-the-art capacitance and potential window, with excellent kinetics and cycle life. The conjugated open-shell donor-acceptor polymer may comprise a plurality of alternating electron-rich monomers (i.e., donors) and electron-deficient monomers (i.e., acceptors) bonded together via a conjugated backbone. The conjugated backbone may comprise a connection of π-orbitals of the plurality of monomers in alternating single and double bonds that facilitates unpaired electron delocalization—thereby stabilizing charge for the polymer. The carbon-based compound of the composite electrode material may provide porous, conductive scaffolds for the composite electrode material, resulting in electrodes scalable to microns-thick films with fast kinetics.
1. A composite electrode material comprising:
an open-shell donor-acceptor polymer comprising a plurality of alternating electron-rich and electron-deficient monomers bonded together via a conjugated backbone, wherein:
the open-shell donor-acceptor polymer includes unpaired electrons when the open-shell donor-acceptor polymer is in a ground state, and
the conjugated backbone comprises a connection of π-orbitals of the plurality of monomers in alternating single bonds and double-bonds that facilitates delocalization of the unpaired electrons; and
a carbon-based compound incorporated into the composite as a conductive matrix.
2. The composite electrode material of claim 1 , wherein the open-shell donor-acceptor polymer comprises alternating bithiophene donors and thiophene substituted thiadiazoloquinoxaline acceptors.
3. The composite electrode material of claim 1 , wherein the open-shell donor-acceptor polymer comprises a side chain-less open-shell donor-acceptor polymer.
4. The composite electrode material of claim 1 , wherein the carbon-based compound comprises reduced graphene oxide (rGO).
5. The composite electrode material of claim 1 , wherein the composite electrode material operates stably at negative voltages with respect to an Ag/Ag+ reference electrode.
6. The composite electrode material of claim 1 , wherein in the carbon-based compound forms porous, conductive scaffolds for the composite electrode material.
7. A supercapacitor comprising:
an anode comprising a composite material, the composite material comprising:
an open-shell donor-acceptor polymer comprising a plurality of alternating electron-rich and electron-deficient monomers bonded together via a conjugated backbone, wherein:
the open-shell donor-acceptor polymer includes unpaired electrons when the open-shell donor-acceptor polymer is in a ground state, and
the conjugated backbone comprises a connection of π-orbitals of the plurality of monomers in alternating single bonds and double bonds that facilitates delocalization of the unpaired electrons; and
a carbon-based compound incorporated into the composite as a conductive matrix.
8. The supercapacitor of claim 7 , wherein the open-shell donor-acceptor polymer comprises alternating bithiophene donors and thiophene substituted thiadiazoloquinoxaline acceptors.
9. The supercapacitor of claim 7 , wherein the open-shell donor-acceptor polymer comprises a side chain-less open-shell donor-acceptor polymer.
10. The supercapacitor of claim 7 , wherein the carbon-based compound comprises rGO.
11. The supercapacitor of claim 7 , wherein the supercapacitor operates at frequencies of 120 hertz (Hz) and above.
12. The supercapacitor of claim 7 , wherein the supercapacitor operates stably over a 3 V range.
13. The supercapacitor of claim 7 , incorporated into a wireless device, wherein the supercapacitor powers the wireless device.
14. The supercapacitor of claim 7 , wherein in the carbon-based compound forms porous, conductive scaffolds for the composite material.