Photoelectrochemical Biofuel Cell Research Articles

Effect of copper doping in the TiO2 film electrodes on the performance of photoelectrochemical biofuel cells

Effect of copper doping in the TiO2 film electrodes on the performance of photoelectrochemical biofuel cells

Photosystem II as a chemiluminescence-induced photosensitizer for photoelectrochemical biofuel cell-type biosensing system

Herein, photosystem II (PSII), extracted from spinach, is used for the first time as an efficient and green sensitizer for a photobioanode in a photoelectrochemical glucose biofuel cell (PBFC) setup. The concept is based on the formation of hemin-catalyzed luminol chemiluminescence (CL) after the enzymatic oxidation of glucose and the simultaneous production of hydrogen peroxide by glucose oxidase. The photosynthetic enzyme PSII, combined with an osmium polymer serving as mediator and photosensitizer, is immobilized and wired on microporous carbonaceous material (MC) for the chemiluminescence-induced oxidation of water to O2 at the photobioanode (GCE|MC|Os polymer|PSII). Also, bilirubin oxidase immobilized on multiwalled carbon nanotubes (MWCNTs) coated electrode (GCE|MWCNT|BOx) serves as a biocathode. The photoelectrochemical biofuel cell (PBFC) is applied to a biosensor model system to validate the appropriateness of such a bioanode operating in a self-powered mode. Os redox polymer attached to MCs provides abundant PSII immobilization and a reliable electron transfer pathway. The well-matching energy levels of photosensitive entities reduce recombination phenomena while MC enhances the charge collection. Substantial photocatalytic water oxidation was observed under CL due to the well-matched CL emission and PSII absorption. The electrode is rationally designed to gain the maximum luminol CL power for the photobioanode. The open circuit potential of PBFC linearly increased with the CL power intensity and, in turn, glucose concentrations in the range of 0–6 mmol L−1. The PBFC yielded an OCP of 0.531 V in 30 mmolL−1 glucose. The study may open a new horizon to the green and pioneering PEC biosensing realm.

Effects of TiO2 nanoparticles and ZnO nanowires photoanodes on photoelectrochemical biofuel cell performances

Effects of TiO2 nanoparticles and ZnO nanowires photoanodes on photoelectrochemical biofuel cell performances

A photoelectrochemical biofuel cell based on a TiO2 nanotube array fluorine-doped tin oxide photoanode

Photoelectrochemical biofuel cells can convert light and chemical energy into electrical energy using a dye-sensitized titania (TiO2) fluorine-doped tin oxide photoanode and a platinum-coated fluorine-doped tin oxide cathode. TiO2 of the photoanode serves both as a support for dyes and as an electron-transporting medium, the structure of which can limit electron trapping and charge transporting and then affect the performance of the photoelectrochemical biofuel cells. TiO2 nanotube array films have been shown to enhance the efficiencies of both charge collection and electron injection, and hence a vertically aligned TiO2 nanotube array is investigated as a conductor for the tetrakis(4-carboxyphenyl)porphyrin dye to construct a new two-compartment photoelectrochemical biofuel cell. The photoelectrochemical biofuel cell containing the TiO2 nanotube array photoanode yields a short-circuit (Isc) current of 110 μA and an open-circuit (Voc) potential of 1010 mV. In contrast, the photovoltaic parameters, Isc and Voc of the photoelectrochemical biofuel cell with the mesoporous TiO2 nanocrystal fluorine-doped tin oxide photoanode, are 96.96 μA and 740 mV, respectively. Photovoltaic measurements show that the maximum incident photon-to-collected electron conversion efficiency was 58% at 430 nm through the spectral range (400–800 nm) for the photoelectrochemical biofuel cell with the TiO2 nanotube array fluorine-doped tin oxide photoanode. These results revealed that the TiO2 nanotube array had great potential for the photoelectrochemical biofuel cells.

Photoelectrochemically-assisted biofuel cell constructed by redox complex and g-C3N4 coated MWCNT bioanode

Herein, we report a membraneless glucose and air photoelectrochemical biofuel cell (PBFC) with a visible light assisted photobioanode. Flavin adenine dinucleotide dependent glucose dehydrogenase (FADGDH) was immobilized on the combined photobioanode for the visible light assisted glucose oxidation (GCE|MWCNT|g-C3N4|Ru-complex|FADGDH) with a quinone mediated electron transfer. Bilirubine oxidase (BOx) immobilized on MWCNT coated GCE (GCE|BOx) was used as the cathode with direct electron transfer (DET). An improvement of biocatalytic oxidation current was observed by 6.2% due in part to the light-driven electron-transfer. The large oxidation currents are probably owing to the good contacting of the immobilized enzymes with the electrode material and the utilization of light assisted process. Under the visible light, the photobioanode shows an anodic photocurrent of 1.95 μA cm2 at attractively low potentials viz. −0.4 vs Ag/AgCl. The lower-lying conduction band of g-C3N4 as compared to Ru-complexes decreases the rate of hole and electron recombination and enhances the charge transportation. The bioanode shows maximum current density for glucose oxidation up to 6.78 μA cm−2 at 0.2 V vs Ag/AgCl at pH:7. The performance of three promising Ru-complexes differing in chemical and redox properties were compared as electron mediators for FADGDH. Upon illumination, the PBFC delivered a maximum power density of 28.5 ± 0.10 μW cm−2 at a cell voltage of +0.4 V with an open circuit voltage of 0.64 V.

Photoanode nanostructure design and electron transport prediction

This paper employs the density functional theory (DFT) to evaluate the effect of different photoanode designs on the electron transport in photoelectrochemical biofuel cells. The electron transfer between different nano structure photoanodes, various sensitizers, and bio-electrolytes are analyzed via the computational quantum mechanics technique. The photoanode employs zinc oxide semiconductors, which have a great potential in cost reduction, higher dye absorption ability and easy production in the industry. Several molecular structure models, such as ZnO nanowires and ZnO nanotubes, with some novel biological pigments have been set up using minimum energy principles. Simulation results reveal that ZnO nanotubes possess lower conduction bands which are potentially easier to transfer electrons from biopigments (e.g., chlorin, chlorophyll a and cyanidin) to the anode to enhance the cell efficiency. In conclusion, the first-principles technique employing the density functional theory is able to predict the multi-electron transport phenomena which cannot be visualized through measurements. It can also be used to screen different design ideas for future green energy applications.

Direct Electron Transfer Mechanisms Applied Toward the Development of an Enhanced Photoelectrochemical Biofuel Cell

Photoelectrochemical biofuel cells (PEBFCs) are hybrid devices which combine the utility of enzymatic redox catalysts with the photon absorbing characteristics of a dye-sensitized solar cell (DSSC). The pairing of these two technologies has been demonstrated to result in a system that improves on the performance of either a traditional enzymatic fuel cell (EFC) or DSSC operating independently1. Furthermore, due to the increased potential provided by a PEBFC relative to an EFC the range of oxidizers used in the cathode can be broadened to produce a variety of useful reduced fuels. Traditionally, PEBFCs have relied on NAD+/NADH intermediates for charge transfer between the anodic redox enzyme and the porphyrin sensitizer. However, recent work by our group has shown that quinoprotein glucose dehydrogenases are capable of efficient, mediator free direct electron transfer (DET) to immobilized heme porphyrins2. DET allows for a further reduction in the electrode overpotential compared to many mediated systems and therefore provides more usable potential for energy conversion. In the current work a PEBFC utilizing DET mechanisms was developed with the goal of providing efficient electron transfer between the enzymatic catalyst and the porphyrin sensitizer on the anode. The electron transfer was enhanced by photo-excitation of the sensitizer and induced charge separation to a covalently bound n-type semi-conductor (Figure 1). The resulting oxidized sensitizer then readily accepts electrons from the quinoproteins adsorbed to the electrode surface. The open circuit potential (Voc) of the illuminated photo anode was more negative than the same anode in a dark condition by approximately 80 mV (top of Figure 2). The generated current of the illuminated photoanode was also considerably higher at all potentials tested (bottom of Figure 2). To complete the PEBFC, the photoanode is coupled with a cathode utilizing an oxidase enzymatic catalyst and overall performance in terms of surface characteristics, Voc, and total power are characterized. Further applications with regards to possible uses in energy conversion and reforming of simple, abundant substrates such as glucose to more readily useable fuels such as hydrogen will be discussed. 1. M. Hambourger, G. Kodis, M. D. Vaughn, G. F. Moore, D. Gust, A. L. Moore and T. A. Moore, Dalton Transactions, 9979 (2009). 2. R. J. Lopez, S. Babanova, K. Artyushkova and P. Atanassov, Bioelectrochemistry, 105, 78 (2015). Figure 1

Automatic illumination compensation device based on a photoelectrochemical biofuel cell driven by visible light.

Inverted illumination compensation is important in energy-saving projects, artificial photosynthesis and some forms of agriculture, such as hydroponics. However, only a few illumination adjustments based on self-powered biodetectors that quantitatively detect the intensity of visible light have been reported. We constructed an automatic illumination compensation device based on a photoelectrochemical biofuel cell (PBFC) driven by visible light. The PBFC consisted of a glucose dehydrogenase modified bioanode and a p-type semiconductor cuprous oxide photocathode. The PBFC had a high power output of 161.4 μW cm(-2) and an open circuit potential that responded rapidly to visible light. It adjusted the amount of illumination inversely irrespective of how the external illumination was changed. This rational design of utilizing PBFCs provides new insights into automatic light adjustable devices and may be of benefit to intelligent applications.

Photoenergy storage and power amplification strategy in membrane-less photoelectrochemical biofuel cells.

The photoelectrochemical biofuel cell (PBFC) has drawn great attention because of its potential in the conversion of both photoenergy and chemical energy from biomass into electricity. Herein, we proposed a novel integrated PBFC by insetting a third electrode with high efficiency energy storage and release between the bioelectrode and the photoelectrode, resulting in a higher power output than that of the original PBFC.

Titania photoanode prepared by chloroplast biotemplate for photoelectrochemical biofuel cell

Chloroplast was used as a biotemplate to synthesize titania (TiO2) replica which was investigated as a semiconductor to construct a photoelectrochemical biofuel cell (PEBFC). The cylindrical stack structure of granum in chloroplast was retained in TiO2 replica by ultrasonication (sonicated-TiO2), while the chloroplast structure was retained for the prepared TiO2 replica under the same condition without ultrasonication (unsonicated-TiO2). The sonicated-TiO2 exhibited a much greater specific surface area (up to 47.8 m2/g) than the unsonicated-TiO2 (26.5 m2/g), which resulted in the sonicated-TiO2 having a better performance than the unsonicated-TiO2.

Tris(hydroxymethyl)aminomethane photooxidation on titania based photoanodes and its implication for photoelectrochemical biofuel cells

In many photoelectrochemical biofuel cells tris(hydroxymethyl)aminomethane (TRIS) is used a buffer. We show that TRIS can be readily photooxidised on titania electrodes. Combining a titania nanotube photoanode in a TRIS buffer with an air-breathing enzymatic biocathode we construct a relatively efficient photoelectrochemical biofuel cell using the TRIS buffer as fuel. This shows both the prospect of using air-breathing bio-cathodes in this kind of cells, but more importantly, shows the need for caution when using TRIS as buffer in photoelectrochemical applications.

Enzyme-catalyzed biocathode in a photoelectrochemical biofuel cell

A novel double-enzyme photoelectrochemical biofuel cell (PEBFC) has been developed by taking glucose dehydrogenase (GDH) and horseradish peroxidase (HRP) as the enzyme of the photoanode and biocathode to catalyze the oxidation of glucose and the reduction of oxygen. A H2-mesoporphyrin IX is used as a dye for a TiO2 film electrode to fabricate a photoanode. The horseradish peroxidase (HRP) is immobilized on a glassy carbon (GC) electrode to construct a biocathode which is used to catalyze the reduction of oxygen in the PEBFC for the first time. The biocathode exhibits excellent electrocatalytic activity in the presence of O2. The performances of the PEBFC are obtained by current–voltage and power-voltage curves. The short-circuit current density (Isc), the open-circuit voltage (Voc), maximum power density (Pmax), fill factor (FF) and energy conversion efficiency (η) are 439 μA cm−2, 678 mV, 79 μW cm−2, 0.39 and 0.016%, respectively, and the incident photon-to-collected electron conversion efficiency (IPCE) is 32% at 350 nm. The Isc is higher than that of the PEBFC with Pt cathode, and the Voc is higher than that of the dye-sensitized solar cell or the enzyme-catalyzed biofuel cell operating individually, which demonstrates that the HRP is an efficient catalyst for the biocathode in the PEBFC.

Photoanode of Photoelectrochemical Biofuel Cell Sensitized by Magnesium Tetraphenylporphyrin

Magnesium tetraphenylporphyrin (MgTPP) had been synthesized with tetraphenylporphyrin (TPP) and magnesium acetate according to reported paper. The photoanode of photoelectrochemical biofuel cell (PEBFC) was constructed including TiO2 conductive film and photosensitizer Magnesium Tetraphenylporphyrin. The interaction between MgTPP sensitizer and TiO2 was evaluated by X-ray photoelectron spectra, indicating that the MgTPP adsorbed on TiO2 was easier to accept electrons compared with synthesized MgTPP itself. The spectroscopic properties of synthesized MgTPP and MgTPP-sensitization TiO2 in dichloromethane solution were obtained by Uv-vis absorption spectra, demonstrating that the characteristic absorption peaks of MgTPP on TiO2 displayed slight red shift compared with synthesized MgTPP. The photocurrent action spectrum evidenced that current of the PEBFC originated from MgTPP-sensitization TiO2 photoanode.

A photoelectrochemical biofuel cell sensitized by [Ru(H2dcbpy)3]Cl2 on TiO2 film

[Ru(H2dcbpy)3]Cl2 (H2dcbpy = 2,2′-bipyridine-4,4′-dicarboxylic acid) has been investigated as a dye for the titanium dioxide (TiO2) film electrode to construct a new one-compartment photoelectrochemical biofuel cell. Light-harvesting capacity of the dye has been evaluated by UV–vis absorption spectra, indicating that absorption peak of the dye is 495 nm. Photovoltaic measurement has shown that maximum incident photon-to-collected electron conversion efficiency is 7.50 % at 490 nm through spectral range of 400–800 nm, which is in agreement with the result of UV–vis absorption spectra. From current–voltage curve open-circuit voltage, short-circuit current density, maximum power density and overall energy conversion efficiency have been observed to be 688 mV, 522 μA/cm2, 124 μW/cm2 and 0.124 %, respectively. These results reveal that [Ru(H2dcbpy)3]Cl2 dye has good photochemical and photoelectrochemical properties.

Photoelectrochemical biofuel cell with dendrimer-encapsulated CdSe nanoparticles-sensitized titanium dioxide as the photoanode

The direct generation of electrical energy from sunlight and a biomass solution with use of a photoelectrochemical biofuel cell (PEBFC) was investigated. The PEBFC was constructed from dendrimer-encapsulated CdSe nanoparticles-sensitized titanium dioxide (TiO2/CdSe-DENs) as the photoanode, along with dendrimer-encapsulated Pt nanoparticles (Pt-DENs) as the cathode and the proton exchange membrane (PEM). The morphology of the TiO2/CdSe-DENs and Pt-DENs on carbon paper was characterized by scanning electron microscopy (SEM), and the effects of the TiO2/CdSe-DENs deposited on the carbon paper and the glucose concentration in the electrolyte on the photoelectrochemical responses were studied through photoelectrochemical measurements. Based on the optimal conditions, an open circuit voltage of 0.5 V and a maximum power density of 40 μW cm−2 could be obtained under light irradiation (λ > 400 nm) from the CdSe-DENs sensitized PEBFCs, indicating that the CdSe-DENs are efficient photosensitizers for PEBFCs.

Photovoltaic Study of Photoelectrochemical Biofuel Cells Sensitized by Porphyrin Derivatives with Different Substituents

Two porphyrin derivatives with different substituents were investigated as dyes for the titanium dioxide (TiO2) film electrode to construct new two-compartment photoelectrochemical biofuel cells (PEBFCs). The two porphyrin derivatives were tetrakis(4-carboxyphenyl)porphyrin (TCPP) and meso-tetra(p-hydroxyphenyl)porphine (THPP). To determine how cell performance was affected by the dye with different substituents, we analyzed the photochemical and photoelectrochemical properties of the two dyes by physical characterization and photoelectrochemical experiments. The UV–Vis absorption spectra and X-ray photoelectron spectra indicated that the interactions between the dye and TiO2 decreased in the order of TCPP > THPP, which was also in accord with the results of Fourier transform infrared. In addition, TCPP and THPP were calculated using the density functional theory and the time-dependent density functional theory, and the calculation result exhibited that the radiative lifetime decreased in the order of TCPP > THPP. Compared with THPP, TCPP with longer excited-state was expected to enhance the performance of a PEBFC. We measured and compared the incident photon-to-collected electron conversion efficiency and the light-to-electrical conversion efficiency (η) of the porphyrin-sensitized photoelectrochemical biofuel cell. The photovoltaic characteristics showed the TCPP was more effective compared to the THPP, which obviously showed that the experimental results were consistent with theoretical expectation. These results revealed that the kind of the substituent for the porphyrin influenced the photovoltaic properties of the PEBFC.

Enhancement of photovoltaic performance of photoelectrochemical biofuel cells by β-functionalized porphyrin sensitizers

Extending excited-state of sensitizer that absorbs visible photon and produces charge separation is of importance for a photoelectrochemical biofuel cell (PEBFC). In the present work, the dependence of series of porphyrins functionalized at β-positions as sensitizers' structures on their excited-state are analyzed with the density functional theory and time-dependent density functional theory. The calculated results expect that the radiative lifetime decreases in the order of haematoporphyrin > protoporphyrin IX > H2-mesoporphyrin IX. The designed PEBFCs with the above porphyrins as sensitizers are assembled, in which the photocurrent action spectra testifies that the order of the radiative lifetime is consistent with that of the incident photon-to-collected electron conversion efficiency (IPCE) value based on the series of porphyrins. All the experimental characteristics show that the porphyrin with ethanol group (–CHOH–CH3) at β-positions can enhance the photovoltaic performance of the PEBFC as expected.

Photoelectrochemical biofuel cells based on H2-mesoporphyrin IX or Zn-mesoporphyrin IX sensitizer on titanium dioxide film electrode

H2-mesoporphyrin IX and Zn-mesoporphyrin IX have been investigated as sensitizers for the titanium dioxide (TiO2) film electrode to construct a new two-compartment photoelectrochemical biofuel cell (PEBFC). The PEBFC can convert the light and chemical energy to electricity by consuming photons and oxidizing glucose. The two sensitizers are similar with two carboxyl anchoring groups, except that the central hydrogen atoms in the H2-mesoporphyrin IX are replaced by zinc. To determine how cell performance is affected by the sensitizer, we analyze the photochemical and photoelectrochemical properties of the two sensitizers by physical characterization and photoelectrochemical experiments. The UV–Vis absorption spectra and X-ray photoelectron spectra (XPS) indicate that the interactions between the sensitizer and TiO2 decrease in the order of H2-mesoporphyrin IX > Zn-mesoporphyrin IX. The interactions are also determined by Fourier transform infrared (FTIR) spectra which indicate that the two sensitizers are adsorbed on the TiO2 film through the carboxyl groups. The photovoltaic characteristics show the Zn-mesoporphyrin IX is less effective in comparison with the H2-mesoporphyrin IX, since the Zn-mesoporphyrin IX enhances the back electron-transfer process, producing lower IPCE and current. These results reveal that the H2-mesoporphyrin IX is a more efficient sensitizer compared with the Zn-mesoporphyrin IX for the PEBFC.

Natural Chlorophyll-Sensitized Nanocrystalline TiO<sub>2</sub> as Photoanode of a Hybrid Photoelectrochemical Biofuel Cell

A photoelectrochemical biofuel cell (PEBFC) generating electrical energy directly from sunlight and biomass was investigated. In this paper, the PEBFC had a natural chlorophyll-sensitized titanium dioxide (TiO2) film photoanode and Pt black cathode. The electron transport process of the PEBFC was described. The performances of the PEBFC were obtained by photocurrent-photovoltage characteristic curves. The open-circuit photovoltage (Voc), the short-circuit photocurrent (Isc) and the maximum power density (Pmax) is 0.53V, 1.000 μAcm-2 and1.1520 μWcm-2 at 0.37 V, respectively. The incident photo-to-current efficiency (IPCE) is 8.4% at 380 nm.

A hybrid photoelectrochemical biofuel cell based on the photosensitization of a chlorophyll derivative on TiO2 film

A hybrid photoelectrochemical biofuel cell is composed of a TiO2 film conductive glass electrode sensitized by a copper chlorophyll trisodium salt in combination with the platinized cathode and the electrolyte which contains redox mediator and enzyme as catalyst. The photovoltaic measurements indicate the optimal dye-adsorption time is 4 h and the incident photon-to-collected electron conversion efficiency is 16% at 400 nm. From the current-voltage curve the open-circuit voltage, short-circuit current density, maximum power density and overall energy conversion efficiency are 468 mV, 482 mu A/cm(2), 97 mu W/cm(2) and 9.7%, respectively. (C) 2011 Elsevier BM. All rights reserved.