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

Abstract

The concept of supercapacitive photo‐bioanode and biosolar cell (photo‐biosupercapacitor) for simultaneous solar energy conversion and storage is demonstrated for the first time. Exploiting the capacitive component significantly improves the electron transfer processes and allows the achievement of a current density of 280 µA cm−2 in the pulse mode.

A Z‐Scheme‐Inspired Photobioelectrochemical H2O/O2 Cell with a 1 V Open‐Circuit Voltage Combining Photosystem II and PbS Quantum Dots

“…Since O 2 and H 2 Oa re recycled between photobioanode and biocathode,t he cell can operate in ac losed system without the need for diffusible mediators, sacrificial agents,o ro ther biofuels.M oreover,t his PBC represents the first example in which the photobioanode and the biocathode can be arranged sandwich-like and the illumination is realized through the transparent IO-ATO electrode,o vercoming the need to arrange the electrodes laterally to each other and saving space.C ompared to other PBCs exploiting isolated PSII or thylakoid membranes,t he cell described in this work provides a0 .5-0.6 Vh igher OCV and a3 -to9 0-fold higher power density. [24][25][26] Theoperational stability of the PBC is currently moderate (see Figure S18), which is in agreement with previously reported PSII-based anodes [35] and can be attributed to the short lifetime of PSII. [36]…”

Fuel-independent and membrane-less self-charging biosupercapacitor

“…1C), the charge-storing ability of the hybrid biodevice was limited by the Mb/NP (-) . Utilization of threedimensional BOx/AuNPs biocathodes for bioelectrocatalytic oxygen reduction has been well established in recent works related to supercapacitive enzymatic fuel cells 18 and biosolar cells 19 24 The stabilised SCBSC was discharged by applying a current pulse of 10 µA cm -2 for 1 s, which leads to a voltage drop of 0.19 ± 0.02 V, which remains constant for at least 20 following cycles of continuous charge/discharge operation. The overall capacitance of the SCBCS calculated from fast galvanostatic discharge was 25% lower than the expected value considering the capacitance of the separate bioelectrodes calculated from CVs, following a common antithetical correlation between the capacitance and scan (or discharge) rate for pseudocapacitive materials.…”

Graphene-conducting polymer nanocomposites for enhancing electrochemical capacitive energy storage

“…Nanostructured Gr/CP surfaces, being a promising matrix for the entrapment of various bioelements (living cells [83], protein complexes [84], redox enzymes [85], etc. ), offer further opportunities for the development of supercapacitive biofuel cells [86,87] and photo-bioelectrochemical cells [88] (in other words, self-charging biosupercapacitors (BioSCs) and photo-BioSCs) with improved performance and prospects for miniaturization of devices.…”