High performance thylakoid bio-solar cell using laccase enzymatic biocathodes

Abstract

Thylakoid membranes have previously been used for electrochemical solar energy conversion, but the current output and open circuit voltage are low, in part due to limitations of the cathode. In this paper, a thylakoid bioanode and laccase biocathode were combined in the construction of a bio-solar cell capable of light-induced generation of electrical power. This two-compartment cell showed a greater than 5-fold increase in short circuit current density and an open circuit voltage 0.275 V larger than that of a thylakoid bio-solar cell incorporating an air-breathing Pt cathode. The electrodes were then tested in several solutions of varying pH to evaluate the possibility of constructing a compartment-less bio-solar cell. This membrane-less cell, operating at pH 5.5, generated a short circuit photocurrent density of 14.0 ± 1.8 μA cm(-2) which is 25% larger than the two-compartment cell and a similar open circuit voltage of 0.720 ± 0.018 V.

The photobioelectrochemical activity of thylakoid bioanodes is increased via photocurrent generation and improved contacts by membrane-intercalating conjugated oligoelectrolytes

“…The same bioanode electrodes were accordingly employed in two-compartment bio-solar cells 45 to further probe whether the amperometric trends hold and whether COEs improve (a) photocurrent generation within the thylakoids or (b) the thylakoid-electrode contact for current harvesting-or a combination of (a) and (b). An example of the obtained solar cell data is shown in Fig.…”

“…Herein, immobilization is accomplished via silica encapsulation with catalase, 37 though thylakoid membranes may also be "wired" to osmium redox polymers, 38 suspended with gold nanoparticles and quinones, 39 frozen in an albumin matrix, 40 incorporated in electrochemical cells with various mediators, 41 or tethered to multiwalled carbon nanotubes (MWCNTs). 45,46 The thylakoid active layer absorbs light and generates electrons that are harvested as anodic photocurrent. 43,44 Two-compartment bio-solar cells constructed from spinach thylakoid bioanodes and laccase biocathodes were recently reported.…”

“…2A) and bio-solar cells (Fig. 45 Because of the strong affinity of COEs for lipid bilayers, 1,55 it is reasonable to expect that thylakoid membrane proteins (e.g. As can be seen in the Fig.…”

Regulation of Photosynthetic Electron Transport and Photoinhibition

“…Technical applications are increasingly exploiting the efficiency of photosynthesis for solid-state devices mimicking photovoltaic cells. Photo-electric currents have been achieved with immobilized chloroplasts [7], thylakoid membranes [8-10], PSII [11, 12] or PSI [13-16] core complexes and isolated reaction centres [17-19]. One of the most promising current bio-photovoltaic without using elaborate or expensive surface chemistries is a PSI complex attached to a semiconductor, achieving a photocurrent density of 362 µA/cm 2 and 0.5 V [15].…”

Photobioelectrochemistry: Solar Energy Conversion and Biofuel Production with Photosynthetic Catalysts

“…29 Their thylakoid bioanode was able to generate 2.46 μA/cm 2 when connected with a Pt air-breathing cathode 29 and 14.0 μA/cm 2 with a laccase oxygen reduction biocathode. 49 The OCVs for these cells were 0.46 V and 0.73 V, respectively. They also showed that this system could be used as a self-powered herbicide biosensor which allows for the determination of herbicide in solution based on the decrease in power output when the photobioelectrocatalysis is inhibited, 50 and the different sources of thylakoids have different sensitivities for herbicide detection.…”