Hybrid Glucose/O₂ Biobattery and Supercapacitor Utilizing a Pseudocapacitive Dimethylferrocene Redox Polymer at the Bioanode

Abstract

Small implantable electronic devices require biologically compatible energy sources that are capable of delivering quick high-energy pulses. Combining batteries and supercapacitors allows for high power and energy density while providing both small size and biocompatibility. Here, we report a hybrid supercapacitor/biobattery whereby an oxygen-reducing cathode of bilirubin oxidase immobilized with anthracene-modified carbon nanotubes and tetrabutylammonium bromide-modified Nafion is coupled with a glucose bioanode of flavin adenine dinucleotide-dependent glucose dehydrogenase. The redox polymer, dimethylferrocene-modified linear poly­(ethylenimine), used at the bioanode simultaneously immobilizes enzyme, mediates electron transfer, and acts as a pseudocapacitor where capacitance of the anode scales with increased polymer loading. Both multiwalled carbon nanotubes and carbon felt incorporated into the anode construction improve polymer conductivity, subsequently resulting in further improved anodic capacitance. A supercapacitor/biobattery device of the above configuration results in a specific capacitance of 300 ± 100 F/g, which is over 4 times higher than that of other reported biologically derived supercapacitors.

Supercapacitive Photo‐Bioanodes and Biosolar Cells: A Novel Approach for Solar Energy Harnessing

“…[4] Utilization of intact TMs allows retention of integral protein complexes in their native conditions. [13] Drawing on the advantages of photo-bioanodes (PBAs) and employing the combination of TMs with RPs and the recently disclosed principle of simultaneous generation and storage of electric power, [14] we have developed double-featured supercapacitive biosolar cells for simultaneous solar energy conversion and storage in the form of electric charge (Scheme 1). [5] A variety of different strategies have been applied to immobilize a functional TM layer on electrode surfaces, e.g., direct adsorption, [5] immobilization during electroplating, [6] immobilization in the presence of conjugated oligoelectrolytes [7] or in an albumin matrix, [8] as well as using soluble mediators to improve the electron shuttling between the TM and the electrode.…”

An Intrinsic Self‐Charging Biosupercapacitor Comprised of a High‐Potential Bioanode and a Low‐Potential Biocathode

“…Most of these devices are based on carbon materials, conducting polymers, and/or metal oxides . In contrast, only a few papers report the use of redox polymers for the fabrication of supercapacitors including ferrocene, hydroquinone, or Os complex modified polymers . The capacitance of these systems is directly related to the amount of the immobilized redox polymer.…”

“…Evidently, no external power source is required for charging the capacitor . This approach was successfully demonstrated by using carbon nanotubes or nano‐porous gold matrices, conducting polymers, or redox polymers as the charge storing capacitance matrix. In these systems, charges generated by oxidation or reduction reactions catalyzed by the immobilized enzymes are transferred to the corresponding storage matrix either by means of direct electron transfer to/from the electrode material or in a mediated electron transfer reaction between the biocatalyst and the redox mediator.…”

“…Evidently, this should be taken into account for the design of novel redox polymers when aiming for their use as charge storing matrixes. If the generation of the capacitance is exclusively based on a faradaic process, the corresponding capacitor is called a pseudo‐capacitor (high pseudo‐capacitance, low double‐layer capacitance) . Thus, devices based on flat electrodes with small double‐layer capacitance coated with thick polymer/enzyme films reveal a rather high pseudo‐capacitance.…”

Electronic structure of cyclodextrin–carbon nanotube composite films

“…Various glucose bio anodes, with incorporation of carbon nanotubes (CNTs), are now being heavily investigated with an eye towards applications, such as enzymatic fuel cells, bio batteries, and biosensors. [2][3][4][5][6] The hybrid glucose bio battery and supercapacitor have also been recently reported, where an efficient glucose bio-anode with carbon nanotubes or polymers was highlighted. 5 The CNT may well lead to improve electron transfer from the enzymes to the electrodes as well as provide a good substrate for the immobilizing enzymes within designed CNT networks.…”