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5. Cable bacteria as long-range biological semiconductors

Author

Bonné, Robin, Hou, Ji-Ling, Hustings, Jeroen, Meert, Mathijs, Hidalgo-Martinez, Silvia, Cornelissen, Rob, D'Haen, Jan, Thijs, Sofie, Vangronsveld, Jaco, Valcke, Roland, Cleuren, Bart, Meysman, Filip J. R., and Manca, Jean V.

Subjects
Physics - Biological Physics, Condensed Matter - Materials Science
Abstract

Filamentous cable bacteria exhibit unprecedented long-range biological electron transport, which takes place in a parallel fibre structure that shows an extraordinary electrical conductivity for a biological material. Still, the underlying electron transport mechanism remains undisclosed. Here we determine the intrinsic electrical properties of individual cable bacterium filaments. We retrieve an equivalent electrical circuit model, characterising cable bacteria as resistive biological wires. Temperature dependent experiments reveal that the charge transport is thermally activated, and can be described with an Arrhenius-type relation over a broad temperature range (-196{\deg}C to +50{\deg}C), thus excluding metal-like electron transport. Furthermore, when cable bacterium filaments are utilized as the channel in a field-effect transistor, they show n-type transport, indicating that electrons rather than holes are the charge carriers. Electron mobilities are in the order of 10$^{-1}$ cm$^2$/Vs, comparable to many organic semiconductors. This new type of biological centimetre-range semiconductor with low resistivity offers new perspectives for both fundamental studies and applications in (bio)electronics., Comment: 19 pages, including supplementary information

Published
2019

14. Phase Engineering via Aluminum Doping Enhances the Electrochemical Stability of Lithium‐Rich Cobalt‐Free Layered Oxides for Lithium‐Ion Batteries

Author

De Sloovere, Dries, primary, Mylavarapu, Satish Kumar, additional, D'Haen, Jan, additional, Thersleff, Thomas, additional, Jaworski, Aleksander, additional, Grins, Jekabs, additional, Svensson, Gunnar, additional, Stoyanova, Radostina, additional, Jøsang, Leif Olav, additional, Prakasha, Kunkanadu Rajappa, additional, Merlo, Maximiliano, additional, Martínez, Elías, additional, Nel‐lo Pascual, Marc, additional, Jacas Biendicho, Jordi, additional, Van Bael, Marlies K., additional, and Hardy, An, additional

Published
2024
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18. Phase Engineering via Aluminum Doping Enhances the Electrochemical Stability of Lithium-Rich Cobalt-Free Layered Oxides for Lithium-Ion Batteries

Author

De Sloovere, Dries, Mylavarapu, Satish Kumar, D'Haen, Jan, Thersleff, Thomas, Jaworski, Aleksander, Grins, Jekabs, Svensson, Gunnar, Stoyanova, Radostina, Jøsang, Leif Olav, Prakasha, Kunkanadu Rajappa, Merlo, Maximiliano, Martinez, Elias, Nel-lo Pascual, Marc, Jacas Biendicho, Jordi, Van Bael, Marlies K., Hardy, An, De Sloovere, Dries, Mylavarapu, Satish Kumar, D'Haen, Jan, Thersleff, Thomas, Jaworski, Aleksander, Grins, Jekabs, Svensson, Gunnar, Stoyanova, Radostina, Jøsang, Leif Olav, Prakasha, Kunkanadu Rajappa, Merlo, Maximiliano, Martinez, Elias, Nel-lo Pascual, Marc, Jacas Biendicho, Jordi, Van Bael, Marlies K., and Hardy, An

Abstract

Lithium-rich, cobalt-free oxides are promising potential positive electrode materials for lithium-ion batteries because of their high energy density, lower cost, and reduced environmental and ethical concerns. However, their commercial breakthrough is hindered because of their subpar electrochemical stability. This work studies the effect of aluminum doping on Li1.26Ni0.15Mn0.61O2 as a lithium-rich, cobalt-free layered oxide. Al doping suppresses voltage fade and improves the capacity retention from 46% for Li1.26Ni0.15Mn0.61O2 to 67% for Li1.26Ni0.15Mn0.56Al0.05O2 after 250 cycles at 0.2 C. The undoped material has a monoclinic Li2MnO3-type structure with spinel on the particle edges. In contrast, Al-doped materials (Li1.26Ni0.15Mn0.61-xAlxO2) consist of a more stable rhombohedral phase at the particle edges, with a monoclinic phase core. For this core-shell structure, the formation of Mn3+ is suppressed along with the material's decomposition to a disordered spinel, and the amount of the rhombohedral phase content increases during galvanostatic cycling. Whereas previous studies generally provided qualitative insight into the degradation mechanisms during electrochemical cycling, this work provides quantitative information on the stabilizing effect of the rhombohedral shell in the doped sample. As such, this study provides fundamental insight into the mechanisms through which Al doping increases the electrochemical stability of lithium-rich cobalt-free layered oxides.

Published
2024
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20. Photoluminescence of Germanium-Vacancy Centers in Nanocrystalline Diamond Films: Implications for Quantum Sensing Applications

Author

Mary Joy, Rani, primary, Pobedinskas, Paulius, additional, Bourgeois, Emilie, additional, Chakraborty, Tanmoy, additional, Goerlitz, Johannes, additional, Herrmann, Dennis, additional, Noel, Celine, additional, Heupel, Julia, additional, Jannis, Daen, additional, Gauquelin, Nicolas, additional, D’Haen, Jan, additional, Verbeeck, Johan, additional, Popov, Cyril, additional, Houssiau, Laurent, additional, Becher, Christoph, additional, Nesládek, Miloš, additional, and Haenen, Ken, additional

Published
2024
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23. The effect of microstructure and film composition on the mechanical properties of linear antenna CVD diamond thin films

Author

Joy, Rani Mary, primary, Pobedinskas, Paulius, additional, Baule, Nina, additional, Bai, Shengyuan, additional, Jannis, Daen, additional, Gauquelin, Nicolas, additional, Pinault-Thaury, Marie-Amandine, additional, Jomard, François, additional, Sankaran, Kamatchi Jothiramalingam, additional, Rouzbahani, Rozita, additional, Lloret, Fernando, additional, Desta, Derese, additional, D’Haen, Jan, additional, Verbeeck, Johan, additional, Becker, Michael Frank, additional, and Haenen, Ken, additional

Published
2023
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28. A study of quenching approaches to optimize ultrasonic spray coated perovskite layers scalable for PV

Author

Silvano Joao, Sala Jacopo, Merckx Tamara, Kuang Yinghuan, Verding Pieter, D'Haen Jan, Aernouts Tom, Vermang Bart, and Deferme Wim

Subjects
quenching, perovskite, photovoltaic, scalable, spray-coating, Renewable energy sources, TJ807-830
Abstract

Perovskite materials have gathered increased interest over the last decade. Their rapidly rising efficiency, coupled with the compatibility with solution processing and thin film technology has put perovskite solar cells (PSC) on the spotlight of photovoltaic research. On top of that, band gap tunability via composition changes makes them a perfect candidate for tandem applications, allowing for further harvest of the solar irradiation spectrum and improved power conversion efficiency (PCE). In order to convert all these advantages into large scale production and have increased dissemination in the energy generation market, perovskite fabrication must be adapted and optimized with the use of high throughput, continuous processes, such as ultrasonic spray coating (USSC). In this paper we investigate the ultrasonically spray coated perovskite layers for photovoltaic applications, with particular focus on the quenching-assisted crystallization step. Different quenching techniques are introduced to the process and compared in terms of final layer morphology and cell performance. Finally, gas quenching is used with the large-scale-compatible deposition and allows the production of perovskite solar cells with PCE >15%.

Published
2022
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32. Germanium vacancy centre formation in CVD nanocrystalline diamond using a solid dopant source

Author

Mary Joy, Rani, Pobedinskas, Paulius, Bourgeois, Emilie, Chakraborty, Tanmoy, Görlitz, Johannes, Herrmann, Dennis, Noël, Celine, Heupel, Julia, Jannis, Daen, Gauquelin, Nicolas, D'Haen, Jan, Verbeeck, Johan, Popov, Cyril, Houssiau, Laurent, Becher, Christoph, Nesládek, Milos, Haenen, Ken, MARY JOY, Rani, POBEDINSKAS, Paulius, BOURGEOIS, Emilie, CHAKRABORTY, Tanmoy, Görlitz, Johannes, Herrmann, Dennis, Noël, Celine, Heupel, Julia, Jannis, Daen, Gauquelin, Nicolas, D'HAEN, Jan, VERBEECK, Johan, Popov, Cyril, Houssiau, Laurent, Becher, Christoph, NESLADEK, Milos, and HAENEN, Ken

Subjects
Chemistry, Nanocrystalline diamond, Chemical vapor deposition, Germanium vacancy, Free-standing diamond film, Photoluminescence, Strain
Abstract

We report the in-situ formation of germanium vacancy (GeV) centres in nanocrystalline diamond (NCD) using chemical vapor deposition (CVD) technique. Commercial Ge wafers are used as the solid dopant source and as substrate. The hydrogen-rich plasma (1% CH4 in H2, 3000 W and 45 Torr, ASTeX 6500 series deposition system) etches the Ge substrate and introduces the GeV complex in the NCD layer. As the melting proximity of Ge and CVD diamond growth temperature introduces limitations; the NCD depositions are restricted to (720 ± 20)°C. Scanning electron microscopy reveal randomly facetted film morphology and Raman measurements confirm diamond formation under the chosen deposition conditions. We discuss an additional challenge, the absence of carbide layer at the Ge-NCD interface, potentially limiting film adhesion to the Ge substrate but at the same time demonstrate self-delaminating free-standing multicrystalline diamond films. Qualitative analysis using time of flight secondary mass ion spectroscopy confirms Ge incorporation, and room temperature photoluminescence (PL) measurements confirm local GeV ensemble formation in diamond films as indicated by the 602 nm PL peak. We also discuss the challenges in using NCD, present low-temperature (10K) PL results and assign strain to explain GeV peak shifts in such material.

Published
2023

33. Facile Aqueous Solution-Gel route toward Thin Film CuBi2O4 Photocathodes for Solar Hydrogen Production

Author

JOOS, Bjorn, ELEN, Ken, VAN DEN HAM, Jonathan, Meulendijks, Nicole, BUSKENS, Pascal, PAULUS, Andreas, WOUTERS, Koen, MANCA, Jean, D'HAEN, Jan, SHUKLA, Sudhanshu, VERMANG, Bart, VAN BAEL, Marlies, HARDY, An, JOOS, Bjorn, ELEN, Ken, VAN DEN HAM, Jonathan, Meulendijks, Nicole, BUSKENS, Pascal, PAULUS, Andreas, WOUTERS, Koen, MANCA, Jean, D'HAEN, Jan, SHUKLA, Sudhanshu, VERMANG, Bart, VAN BAEL, Marlies, and HARDY, An

Subjects
solution-gel synthesis, solar fuels, hydrogen, photoelectrochemical water splitting, semiconductors
Abstract

A new benign aqueous route towards bismuth-containing photoelectrodes is proposed to eliminate the need for harmful organic solvents and/or acids. A CuBi2O4 photocathode was prepared by stabilizing the metal ions through complexation in pH neutral aqueous solutions. Merits of the proposed approach are elemental homogeneity (with unique doping possibilities) and ease of fabrication (e.g. high scalability). The prepared aqueous CuBi2O4 precursor forms a nearly phase-pure kusachiite crystalline phase free of organics residuals and capable of water reduction due to its sufficiently negatively positioned conduction band at -0.4 V vs. RHE. Deposition on FTO/glass substrates and thermal treatment leads to uniform but granular films of CuBi2O4 with excellent control over stoichiometry and thickness, owing to the facile and non-destructive synthesis conditions. Ultimately, the optimized CuBi2O4 photocathodes produced AM1.5G photocurrent densities of up to -1.02 mA∙cm-2 at 0.4 V vs. RHE with H2O2 as an electron scavenger, competing with bare CuBi2O4 prepared through less benign non-aqueous organic synthesis routes.

Published
2023

35. Minimizing the Interface-Driven Losses in Inverted Perovskite Solar Cells and Modules

Author

Zhang, Xin, primary, Qiu, Weiming, additional, Apergi, Sofia, additional, Singh, Shivam, additional, Marchezi, Paulo, additional, Song, Wenya, additional, Sternemann, Christian, additional, Elkhouly, Karim, additional, Zhang, Dong, additional, Aguirre, Aranzazu, additional, Merckx, Tamara, additional, Krishna, Anurag, additional, Shi, Yuanyuan, additional, Bracesco, Andrea, additional, van Helvoirt, Cristian, additional, Bens, Frennie, additional, Zardetto, Valerio, additional, D’Haen, Jan, additional, Yu, Anran, additional, Brocks, Geert, additional, Aernouts, Tom, additional, Moons, Ellen, additional, Tao, Shuxia, additional, Zhan, Yiqiang, additional, Kuang, Yinghuan, additional, and Poortmans, Jef, additional

Published
2023
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37. Minimizing the Interface-Driven Losses in Inverted Perovskite Solar Cells and Modules

Author

Zhang, Xin, Qiu, Weiming, Apergi, Sofia, Singh, Shivam, Marchezi, Paulo, Song, Wenya, Sternemann, Christian, Elkhouly, Karim, Zhang, Dong, Aguirre, Aranzazu, Merckx, Tamara, Krishna, Anurag, Shi, Yuanyuan, Bracesco, Andrea, van Helvoirt, Cristian, Bens, Frennie, Zardetto, Valerio, D’Haen, Jan, Yu, Anran, Brocks, Geert, Aernouts, Tom, Moons, Ellen, Tao, Shuxia, Zhan, Yiqiang, Kuang, Yinghuan, Poortmans, Jef, Zhang, Xin, Qiu, Weiming, Apergi, Sofia, Singh, Shivam, Marchezi, Paulo, Song, Wenya, Sternemann, Christian, Elkhouly, Karim, Zhang, Dong, Aguirre, Aranzazu, Merckx, Tamara, Krishna, Anurag, Shi, Yuanyuan, Bracesco, Andrea, van Helvoirt, Cristian, Bens, Frennie, Zardetto, Valerio, D’Haen, Jan, Yu, Anran, Brocks, Geert, Aernouts, Tom, Moons, Ellen, Tao, Shuxia, Zhan, Yiqiang, Kuang, Yinghuan, and Poortmans, Jef

Abstract

The inverted p-i-n perovskite solar cells hold high promise for scale-up toward commercialization. However, the interfaces between the perovskite and the charge transport layers contribute to major power conversion efficiency (PCE) loss and instability. Here, we use a single material of 2-thiopheneethylammonium chloride (TEACl) to molecularly engineer both the interface between the perovskite and fullerene-C60 electron transport layer and the buried interface between the perovskite and NiOx-based hole transport layer. The dual interface modification results in optimized band alignment, suppressed nonradiative recombination, and improved interfacial contact. A PCE of 24.3% is demonstrated, with open-circuit voltage (Voc) and fill factor (FF) of 1.17 V and 84.6%, respectively. The unencapsulated device retains >97.0% of the initial performance after 1000 h of maximum power point tracking under illumination. Moreover, a PCE of 22.6% and a remarkable FF of 82.4% are obtained for a mini-module with an active area of 3.63

Published
2023

43. Development and Thermo-Mechanical Reliability Assessment of Fiber Reinforced Polymers in Lightweight Pv Modules Towards Vehicle-Integrated Photovoltaics

Author

Luo, Bin, primary, Govaerts, Jonathan, additional, Van Dyck, Rik, additional, Borgers, Tom, additional, Ruttens, Bart, additional, Paesa, Marta Casasola, additional, D'Haen, Jan, additional, Tous, Loic, additional, Radhakrishnan, Hariharsudan Sivaramakrishnan, additional, Daenen, Michael, additional, van Vuure, Aart W., additional, and Poortmans, Jef, additional

Published
2023
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44. Temperature-driven chemical segregation in Co-free Li-rich layered oxides and its influence on electrochemical performance

Author

Kunkanadu Rajappa Prakasha, Jekabs Grins, Jaworski, Aleksander, Thersleff, Thomas, Svensson, Gunnar, Jøsang, Leif Olav, Dyrli, Anne Dalager, Paulus, Andreas, De Sloovere, Dries, D'Haen, Jan, Van Bael, Marlies K., Hardy, An, Hemesh Avireddy, Morante, Joan Ramon, and Biendicho, Jordi Jacas

Abstract

Co-free Li-rich layered oxides are gaining interest as feasible positive electrode materials in lithium-ion batteries (LIBs) in terms of energy density, cost reduction, and alleviating safety concerns. Unfortunately, their commercialization is hindered by the severe structural degradation that occurs during electrochemical operation. The study at hand demonstrates advanced structural engineering of a Li-rich Co-free oxide with composition Li1.1Ni0.35Mn0.55O2 by spray-pyrolysis and subsequent calcination of an aqueous precursor, creating a segregated structure of two distinct layered phases with space groups 𝑅3̅𝑚 (rhombohedral) and 𝐶2/𝑚 (monoclinic) . This particular structure was investigated with powder neutron diffraction, high-resolution analytical transmission electron microscopy imaging, and electron energy loss spectroscopic characterization. This complex structure contributes to the high electrochemical stability and good rate capability observed for this compound (160 mAh/g at C/3 and 100 mAh/g at 1C). These results provide new insights into the feasibility of developing and commercializing of cobalt-free positive electrode materials for LIBs.

Published
2023
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48. Facile Aqueous Solution‐Gel Route toward Thin Film CuBi2O4 Photocathodes for Solar Hydrogen Production.

Author

Joos, Bjorn, Elen, Ken, van den Ham, Jonathan, Meulendijks, Nicole, Buskens, Pascal, Paulus, Andreas, Wouters, Koen, Manca, Jean, D'Haen, Jan, Shukla, Sudhanshu, Vermang, Bart, Van Bael, Marlies, and Hardy, An

Subjects
THIN films, PHOTOCATHODES, HYDROGEN production, CONDUCTION bands, GLASS coatings, PHOTOELECTROCHEMISTRY, INTERSTITIAL hydrogen generation
Abstract

A new benign aqueous route toward bismuth‐containing photoelectrodes is proposed to eliminate the need for harmful organic solvents and/or acids. A CuBi2O4 photocathode is prepared by stabilizing the metal ions through complexation in pH neutral aqueous solutions. Merits of the proposed approach are elemental homogeneity (with unique doping possibilities) and ease of fabrication (e.g., high scalability). The prepared aqueous CuBi2O4 precursor forms a nearly phase‐pure kusachiite crystalline phase free of organics residuals and capable of water reduction due to its sufficiently negatively positioned conduction band at −0.4 V versus RHE. Deposition on fluorine doped tin oxide coated glass (FTO/glass) substrates and thermal treatment leads to uniform but granular films of CuBi2O4 with excellent control over stoichiometry and thickness, owing to the facile and non‐destructive synthesis conditions. Ultimately, the optimized CuBi2O4 photocathodes produce AM1.5G photocurrent densities of up to −1.02 mA cm−2 at 0.4 V versus RHE with H2O2 as an electron scavenger, competing with bare CuBi2O4 prepared through less benign non‐aqueous organic synthesis routes. [ABSTRACT FROM AUTHOR]

Published
2023
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