Sustainable electricity generation from photo-bioelectrochemical cell based on carbon nanotubes and chlorophyll anode
Introduction
Green microalgae are commonly used in the production of fuel (biodiesel and bioethanol), hydrogen, and other value-added chemicals (chlorophyll, protein) (Dixon and Wilken, 2018, Shuba and Kifle, 2018, Ariede et al., 2017, Khetkorn et al., 2017). The relatively simple cellular organization of the algae has provided the advantage of its photosynthetic processes to generate metabolic products.
In recent years, the use of chlorophyll held by plants and microalgae has shown a growing interest in the imitation of natural photosynthetic energy transfer processes (Wang et al., 2018, Dau et al., 2017). This is a step towards replacing non-biological electrochemical catalysts, which are not sustainable and may affect the ecosystem (Guo et al., 2020, Shen et al., 2020, Fu et al., 2019). Several studies have developed the direct transformation of light into electrical energy by photosynthesis in electrical cells using natural systems such as thylakoids, chlorophyll, photosynthesis reaction centers, and all microalgae cells (Carpentier and Mimeault, 1987, Katz et al., 1990, Ptak et al., 1997, McCormick et al., 2011). The electrogenic properties of chlorophyll isolated from green microalgae are particularly worthy of exploration in photo-bioelectrochemical cells for direct power generation.
Chlorophyll direct energy processing as a photo-biocatalyst is preferable to other dyes due to its availability and efficiency in absorbing light. The processes in Photosystem I (PS-I) and II (PS-II) can directly turn light into energy (Duan et al., 2020, Liu et al., 2020). Chlorophyll is readily modified by other biological materials, which renders it an excellent candidate as a photo-biocatalyst (Frias et al., 2018). In addition, natural electrochemical cells provide some distinctive benefits such as (i) low costs and (ii) self-sufficient inorganic substances (Sekar et al., 2014).
Although it has many advantages due to its comparatively low transmission efficiency, the electrochemical cell technology which uses photo-biocatalyst dye is still inadequate for producing a full amount of power towards research implementation (Esper et al., 2006). For this cause, it is important to improve chlorophyll function by using supporting materials including carbon nanotubes (CNTs). CNTs have several advantages such as large specific surfaces, strong conductivity, and exceptional chemical stability as supporting material (Alim et al., 2018).
Few people use chlorophyll in conjunction with other chemicals to produce electricity, where dye synthesized solar cell (DSSC) is commonly used (Siddick et al., 2018, Wang et al., 2019, Mary Rosana et al., 2020, Zhang et al., 2020). To be applied as a biocatalyst anode for photo-bioelectrochemical cells, there are limited records of its alteration in CNTs.
In this study, the direct electron transfer (DET) capability of chlorophyll from Chlorella vulgaris as a photo-biocatalyst was investigated and modified using CNT as supportive material for the current generation of photo-bioelectrochemical cells. This is accomplished by adding chlorophyll to the surface wall of the CNT to form CNT/chlorophyll, which is used as an anode in the cells. This study is an intellectual novelty; hence, it is expected to enable potential research teams to grow green energy dependent on natural dyes.
Section snippets
Chlorophyll extraction
The extraction of Chlorella vulgaris microalgae chlorophyll was performed by using methods from previous studies (Sartory and Grobbelaar, 1984, Simon and Helliwell, 1998). A reflux procedure through a soxhlet system was carried out for two hours using methanol as the solvent for many g of commercial Chlorella powder at 60 °C. Subsequently, the chlorophyll solution was extracted and the same process was replicated by the fresh solvent three times. Quantification of the extracts by UV–Vis was
Morphology analysis
Scanning Electron Microscopy was used to investigate the interaction between MWCNT and chlorophyll, as shown in Fig. 2. Fig. 2a is a pure CNT without chlorophyll. Contrastingly, there were several noticeable changes on the surface morphology of CNT/chlorophyll photo-biocatalyst as shown in Fig. 2b compared to the pure CNT (Fig. 2a). Firstly, the chloroplast granules, that were the origin of chlorophyll, were noticeably attached to the surface of CNT although it was postulated that some of
Conclusions
In this study, a photo-bioelectrochemical cell that adopted an anode system based on CNT-chlorophylls was developed. The anode was designed by CNT through a chlorophyll coating technique, while the extracted chlorophyll was gotten from Chlorella vulgaris microalgae. The CNT/chlorophyll had bandgap energy of 2.72 eV, which was 5% higher than CNT. CV studies were carried out to establish the role of chlorophyll in electricity generation at all anode alteration stages and, in the presence, or
Declaration of Competing Interest
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
Acknowledgments
This research was supported in full with Toray Science & Technology Research Grant 2020 provided by Indonesia Toray Science Foundation.
References (41)
- et al.
Recent uses of carbon nanotubes & gold nanoparticles in electrochemistry with application in biosensing: a review
Biosens. Bioelectron.
(2018) - et al.
Cosmetic attributes of algae – a review
Algal Res.
(2017) - et al.
Construction of conducting polymer/cytochrome C/thylakoid membrane based photo-bioelectrochemical fuel cells generating high photocurrent via photosynthesis
Biosens. Bioelectron.
(2018) - et al.
Photosynthesis as a power supply for (bio-) hydrogen production
Trends Plant Sci.
(2006) - et al.
Electrochemical approach to the development of a photoelectrode on the basis of photosynthetic reaction centers
J. Electroanal. Chem. Interfacial Electrochem.
(1990) - et al.
Microalgal hydrogen production – a review
Bioresour. Technol.
(2017) - et al.
Mediator-free solar energy conversion by the artificially installed thylakoid membrane on the functionalized electrode
Electrochem. Commun.
(2014) - et al.
Determination of accurate extinction coefficients and simultaneous equations for assaying chlorophylls a and b extracted with four different solvents: verification of the concentration of chlorophyll standards by atomic absorption spectroscopy
Biochimica et Biophysica Acta (BBA)-Bioenergetics
(1989) - et al.
Photocurrent kinetics (in the microsecond time range) of chlorophyll a, chlorophyll b and stilbazolium merocyanine solutions in a nematic liquid crystal located in an electrochemical cell
J. Photochem. Photobiol., A
(1997) - et al.
Microalgae to biofuels: ‘Promising’ alternative and renewable energy, review
Renew. Sustain. Energy Rev.
(2018)
An investigation of the dye-sensitized solar cell performance using graphene-titania (TrGO) photoanode with conventional dye and natural green chlorophyll dye
Mater. Sci. Semicond. Process.
Extraction and quantification of chlorophyll a from freshwater green algae
Water Res.
Effect of temperature, oxygen and light on the degradation of β-carotene, lutein and α-tocopherol in spray-dried spinach juice powder during storage
Food Chem.
Synthesis and characterization of multiwalled carbon nanotubes functionalized with chlorophyll-derivatives compounds extracted from Hibiscus tiliaceus
Diam. Relat. Mater.
Chlorophyll-based organic solar cells with improved power conversion efficiency
J. Energy Chem.
A chlorophyll derivative-based bio-solar energy conversion and storage device
Electrochim. Acta
Nanobioarchitectures based on chlorophyll photopigment, artificial lipid bilayers and carbon nanotubes
Beilstein J. Nanotechnol.
High photo-electrochemical activity of thylakoid–carbon nanotube composites for photosynthetic energy conversion
Energy Environ. Sci.
Natural dye senstizers for photoelectrochemical cells
Energy Environ. Sci.
The photosynthetic partial reactions involved in photoelectrochemical current generation by thylakoid membranes
Biotechnol. Lett.
Cited by (7)
Membranes of Multiwall Carbon Nanotubes in Chitosan–Starch with Mechanical and Compositional Properties Useful in Li-Ion Batteries
2023, C-Journal of Carbon ResearchFluorescence quenching in thylakoid membranes induced by single-walled carbon nanotubes
2023, Photochemical and Photobiological SciencesLife in biophotovoltaics systems
2023, Frontiers in Plant ScienceOutstanding Photo-bioelectrochemical Cell by Integrating TiO<inf>2</inf> and Chlorophyll as Photo-bioanode for Sustainable Energy Generation
2022, International Journal of Renewable Energy Development