| 1. |
- Pankratov, Dmitry, et al.
(författare)
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The influence of surface composition of carbon nanotubes on the photobioelectrochemical activity of thylakoid bioanodes mediated by osmium-complex modified redox polymer
- 2019
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Ingår i: Electrochimica Acta. - : Elsevier BV. - 0013-4686. ; 310, s. 20-25
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Tidskriftsartikel (refereegranskat)abstract
- A combination of photosynthetic biocatalysts with high surface area conductive materials mediated by an osmium-complex modified redox polymer (OsRP)holds promising features for the development of sustainable “green” systems for solar energy conversion. In this work we performed a comparative study of two types of carbon nanotubes (CNTs)synthesized by pyrolysis of polymeric precursors. Both CNTs were of similar morphology, but had a different surface C/O ratio. The CNTs were utilized as a support for immobilization of thylakoid membranes, electrochemically wired through the OsRP. The photobioanodes based on the CNTs with a higher C/O ratio exhibit a higher maximum photocurrent density of 97.1 ± 8.3 μA cm −2 at a light intensity of 400 W m −2 with reduced charge transfer resistance, but had lower operational stability. Our results demonstrate the significance of investigating of electrochemical communication between the photosynthetic component, the redox mediator and the support nanomaterial and may offer new opportunities for designing and optimization of mediated bioelectrochemical systems.
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| 2. |
- Shen, Fei, et al.
(författare)
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Supercapacitor/biofuel cell hybrid device employing biomolecules for energy conversion and charge storage
- 2019
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Ingår i: Bioelectrochemistry. - : Elsevier BV. - 1567-5394. ; 128, s. 94-99
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Tidskriftsartikel (refereegranskat)abstract
- We report on a hybrid bioelectrochemical system that integrates an energy converting part, viz. a glucose/oxygen enzymatic fuel cell, with a charge-storing component, in which the redox features of the immobilized redox protein cytochrome c (cyt c) were utilized. Bilirubin oxidase and pyrroloquinoline quinone-dependent glucose dehydrogenase (PQQ-GDH) were employed as the biocatalysts for dioxygen reduction and glucose oxidation, respectively. A bi-protein PQQ-GDH/cyt c signal chain was created that facilitates electron transfer between the enzyme and the electrode surface. The assembled supercapacitor/biofuel cell hybrid biodevice displays a 15 times higher power density tested in the pulse mode compared to the performance achieved from the continuously operating regime (4.5 and 0.3 μW cm −2 , respectively) with an 80% residual activity after 50 charge/discharge pulses. This can be considered as a notable step forward in the field of glucose/oxygen membrane-free, biocompatible hybrid power sources.
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| 3. |
- Shen, Fei, et al.
(författare)
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Two-dimensional graphene paper supported flexible enzymatic fuel cells
- 2019
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Ingår i: Nanoscale Advances. - : Royal Society of Chemistry (RSC). - 2516-0230. ; 1:7, s. 2562-2570
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Tidskriftsartikel (refereegranskat)abstract
- Application of enzymatic biofuel cells (EBFCs) in wearable or implantable biomedical devices requires flexible and biocompatible electrode materials. To this end, freestanding and low-cost graphene paper is emerging among the most promising support materials. In this work, we have exploited the potential of using graphene paper with a two-dimensional active surface (2D-GP) as a carrier for enzyme immobilization to fabricate EBFCs, representing the first case of flexible graphene papers directly used in EBFCs. The 2D-GP electrodes were prepared via the assembly of graphene oxide (GO) nanosheets into a paper-like architecture, followed by reduction to form layered and cross-linked networks with good mechanical strength, high conductivity and little dependence on the degree of mechanical bending. 2D-GP electrodes served as both a current collector and an enzyme loading substrate that can be used directly as a bioanode and biocathode. Pyrroloquinoline quinone dependent glucose dehydrogenase (PQQ-GDH) and bilirubin oxidase (BOx) adsorbed on the 2D-GP electrodes both retain their biocatalytic activities. Electron transfer (ET) at the bioanode required Meldola blue (MB) as an ET mediator to shuttle electrons between PQQ-GDH and the electrode, but direct electron transfer (DET) at the biocathode was achieved. The resulting glucose/oxygen EBFC displayed a notable mechanical flexibility, with a wide open circuit voltage range up to 0.665 V and a maximum power density of approximately 4 μW cm-2 both fully competitive with reported values for related EBFCs, and with mechanical flexibility and facile enzyme immobilization as novel merits.
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| 4. |
- Tang, Yingying, et al.
(författare)
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Lead-free double halide perovskite Cs 3 BiBr 6 with well-defined crystal structure and high thermal stability for optoelectronics
- 2019
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Ingår i: Journal of Materials Chemistry C. - : Royal Society of Chemistry (RSC). - 2050-7534 .- 2050-7526. ; 7:11, s. 3369-3374
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Tidskriftsartikel (refereegranskat)abstract
- Halide perovskites have continued to rise as attractive light absorber materials, mainly driven by their potential wide applications in the fields of solar cells, photodetectors, lasers and others. However, Pb-containing perovskites are poisonous and could cause serious potential problems to our environment. Thus, there is a strong desire to develop lead-free perovskites as environmentally friendly alternatives. Here, we have shown a successful synthesis of a non-toxic single crystalline double-halide perovskite, Cs 3 BiBr 6 , and analysed its structural characteristics in detail. This perovskite represents a new structure in terms of double-halide perovskites. The crystal structure features isolated BiBr 6 polyhedra forming a zero-dimensional halide perovskite. The bandgap of this compound is measured to be 2.55 eV. High thermal stability is also clearly shown in the Cs 3 BiBr 6 single crystal. A photodetector based on this compound is fabricated and tested, which exhibits an impressive detectivity of 0.8 × 10 9 Jones and low dark current under 400 nm light illumination. Overall, our results show that the Cs 3 BiBr 6 perovskite as a lead-free perovskite has interesting structures and promising properties for optoelectronic devices.
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