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10. Design and Optimization of Critical-Raw-Material-Free Electrodes towards the Performance Enhancement of Microbial Fuel Cells.

Author

Nisa, Khair Un, da Silva Freitas, Williane, D'Epifanio, Alessandra, and Mecheri, Barbara

Subjects
ELECTRODE performance, MICROBIAL fuel cells, CLEAN energy, CARBON fibers, RAW materials, CATALYTIC activity
Abstract

Microbial fuel cells (MFCs) are sustainable energy recovery systems because they use organic waste as biofuel. Using critical raw materials (CRMs), like platinum-group metals, at the cathode side threatens MFC technology's sustainability and raises costs. By developing an efficient electrode design for MFC performance enhancement, CRM-based cathodic catalysts should be replaced with CRM-free materials. This work proposes developing and optimizing iron-based air cathodes for enhancing oxygen reduction in MFCs. By subjecting iron phthalocyanine and carbon black pearls to controlled thermal treatments, we obtained Fe-based electrocatalysts combining high surface area (628 m2 g−1) and catalytic activity for O2 reduction at near-neutral pH. The electrocatalysts were integrated on carbon cloth and carbon paper to obtain gas diffusion electrodes whose architecture was optimized to maximize MFC performance. Excellent cell performance was achieved with the carbon-paper-based cathode modified with the Fe-based electrocatalysts (maximum power density-PDmax = 1028 mWm−2) compared to a traditional electrode design based on carbon cloth (619 mWm−2), indicating the optimized cathodes as promising electrodes for energy recovery in an MFC application. [ABSTRACT FROM AUTHOR]

Published
2024
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14. Appendix A. Supplementary data for Hierarchical porous Fe/Ni-based bifunctional oxygen electrocatalysts for rechargeable zinc-air batteries [Dataset]

Author

Ministero degli Affari Esteri e della Cooperazione Internazionale, Sapienza Università di Roma, Ricciardi, Beatrice [0009-0004-1889-3262], da Silva Freitas, Williane [0000-0001-9041-8168], Mecheri, B. [0000-0002-1458-6239], Un Nisa, Khair [0009-0001-0433-4521], Montero, Jorge [0000-0003-2570-1404], Ficca, Valerio C.A. [0000-0002-9817-3027], Placidi, Ernesto [0000-0002-3820-8451], Alegre Gresa, Cinthia [0000-0003-1221-6311], D'Epifanio, Alessandra [0000-0002-4257-7399], Mecheri, B. [barbara.mecheri@uniroma2.it], Ricciardi, Beatrice; da Silva Freitas, Williane; Un Nisa, Khair; Montero, Jorge; Ficca, Valerio C.A., Ricciardi, Beatrice, da Silva Freitas, Williane, Mecheri, B., Un Nisa, Khair, Montero, Jorge, Ficca, Valerio C.A., Placidi, Ernesto, Alegre Gresa, Cinthia, D'Epifanio, Alessandra, Ministero degli Affari Esteri e della Cooperazione Internazionale, Sapienza Università di Roma, Ricciardi, Beatrice [0009-0004-1889-3262], da Silva Freitas, Williane [0000-0001-9041-8168], Mecheri, B. [0000-0002-1458-6239], Un Nisa, Khair [0009-0001-0433-4521], Montero, Jorge [0000-0003-2570-1404], Ficca, Valerio C.A. [0000-0002-9817-3027], Placidi, Ernesto [0000-0002-3820-8451], Alegre Gresa, Cinthia [0000-0003-1221-6311], D'Epifanio, Alessandra [0000-0002-4257-7399], Mecheri, B. [barbara.mecheri@uniroma2.it], Ricciardi, Beatrice; da Silva Freitas, Williane; Un Nisa, Khair; Montero, Jorge; Ficca, Valerio C.A., Ricciardi, Beatrice, da Silva Freitas, Williane, Mecheri, B., Un Nisa, Khair, Montero, Jorge, Ficca, Valerio C.A., Placidi, Ernesto, Alegre Gresa, Cinthia, and D'Epifanio, Alessandra

Abstract

Figure S1: Thermogravimetric (TG) analysis of 2Ni1Fe-NC precursor and NC_d. Figure S2: SEM images of 2Ni1Fe-NC, 2Ni1Fe-NC_a, 2Ni1Fe-NC_b, 2Ni1Fe-NC_c and 2Ni1Fe-NC_d and NC_d. Figure S3: X-ray diffractograms of NC_d. Table S1: Comparison of the bifunctionality performance of oxygen evolution and reduction reactions of electrocatalysts PGM-free (KOH 0.1-1 M). Figure S4: SEM images of 1Ni1Fe-NC. Figure S5: Isotherm and BJH analysis of 1Ni1Fe-NC. Figure S6: X-ray diffractograms of 1Ni1Fe-NC. Figure S7: HAADF-STEM, STEM-EDS, and TEM images of sample 1Ni1Fe-NC. Figure S8: TEM images of sample 2Ni1Fe-NC and 1Ni1Fe-NC. XPS methodology. Figure S9: O1s and Fe2p spectra of 1Ni1Fe-NC. Figure S10: O1s and Fe2p spectra of 2Ni1Fe-NC. Figure S11: C1s spectra of 2Ni1Fe-NC_a, 2Ni1Fe-NC_b, 2Ni1Fe-NC_c. Figure S12: N1s spectra of 2Ni1Fe-NC_a, 2Ni1Fe-NC_b, 2Ni1Fe-NC_c. Figure S13: O1s spectra of 2Ni1Fe-NC_a, 2Ni1Fe-NC_b, 2Ni1Fe-NC_c. Figure S14: Ni2p3/2 spectra of 2Ni1Fe-NC_a, 2Ni1Fe-NC_b, 2Ni1Fe-NC_c. Figure S15: Fe2p spectra of 2Ni1Fe-NC_a, 2Ni1Fe-NC_b, 2Ni1Fe-NC_c. Table S2: C1s Chemical speciation of the samples. Table S3: N1s Chemical speciation of the samples. Table S4: Ni2p3/2 Chemical speciation of the samples. Table S5: O1s Chemical speciation of the samples. Table S6: Fe2p Chemical speciation of the samples. Figure S16: ORR-polarization curves of Pt/C. Figure S17: OER-polarization curves of RuO2. Figure S18: Ring current and peroxide yield of 1Ni1Fe-NC and 2Ni1Fe-NC. Figure S19. Power density and polarization curves of 1Ni1Fe-NC and 2Ni1Fe-NC. Table S7: Performance of PGM-free materials as Air Cathodes in ZABs. References., XPS methodology: The shake-up, plasmon loss, and multiplet structures are always present and cannot be neglected in the identification of specific compounds. Following the criteria of the mentioned studies, based on pure refence compounds of Ni, the 2p core level of metallic Ni is commonly fitted using three structures (the main peak at 852.6 eV and two additional broad satellites accounting for multiple surface and bulk plasmons and inter-band transitions). In the case of oxides, fit of Ni(OH)2 and NiOOH can be performed using the free ions parameters for Ni2+ and Ni3+ calculated by Gupta and Sen [19,20] but introducing an additional broad component around 858 eV, underneath the valley between the main peaks and satellites, due to inter-band losses. For these oxides, 3+1 main peaks and 3 satellites (Ni2+), and 4+1 main peaks and 2 satellites (Ni3+) are respectively needed. Regarding NiO, all the mentioned features can overlap, commonly with a shift in binding energies, creating uncertainty in the assignment of components for mixed chemical states. In addition, as reported from the XRD section, the presence of the two metals is correlated to the Fe alloys of Ni, for example nickel ferrite (Ni(II)Fe(III)2O4), along with oxides. Nickel ferrite is fitted with 2 main peaks and 3 satellites.[21] To provide a reliable quantification of our samples, the use of those set of fits is required, based on constrained parameters, such as intensity of peaks, positions, and full width at half maximum (FWHM)).[22] Still, the FWHM of peaks is usually correlated to the instrumentation employed; hence can be useful to relax the constraints on such parameters. From the literature, Ni(II) and Ni(III) are commonly assigned respectively around 854.6 eV and 856.1eV, [21–23] however the assignment is not straightforward since NiO (Ni(II)) is characterized by the main component centered at 855.4 eV and a peculiar feature at 853.7 eV in addition to a broad satellite around 861 eV. Due to such

Published
2023

25. Development and Optimization of Air-Electrodes for Rechargeable Zn–Air Batteries.

Author

Nisa, Khair Un, da Silva Freitas, Williane, Montero, Jorge, D'Epifanio, Alessandra, and Mecheri, Barbara

Subjects
STORAGE batteries, OXYGEN evolution reactions, CLEAN energy, ENERGY density, OXYGEN reduction, CATHODES, ELECTRIC charge
Abstract

Rechargeable Zn–air batteries (ZABs) can play a significant role in the transition to a cleaner and more sustainable energy system due to their high theoretical energy density, high cell voltage, and environmental friendliness. ZAB's air cathode is the principal determinant in predicting the battery's overall performance, as it is responsible for catalyzing the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) during the discharging and charging process, respectively. In this work, a detailed optimization study of the architecture of the air cathode was carried out using the benchmark bifunctional oxygen electrocatalyst (Pt/C-RuO2). The air cathode composition and architecture were optimized regarding the choice of the commercial gas diffusion layer (GDL), the effect of hot pressing the catalyst layer (CL), and the optimum pore size of the current collector. The best cathode from this study shows a maximum power density (PDmax) of 167 mW/cm2, with a round trip efficiency and a voltage gap (Egap) of 59.8% and 0.78 V, respectively, indicating the air cathodes preparation approach proposed in this work as a promising strategy for the improvement of the overall performance of ZABs. [ABSTRACT FROM AUTHOR]

Published
2023
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42. A Neutral‐pH Aqueous Redox Flow Battery Based on Sustainable Organic Electrolytes.

Author

Montero, Jorge, da Silva Freitas, Williane, Mecheri, Barbara, Forchetta, Mattia, Galloni, Pierluca, Licoccia, Silvia, and D'Epifanio, Alessandra

Subjects
FLOW batteries, ORGANIC bases, OXIDATION-reduction reaction, ELECTROLYTES
Abstract

Aqueous organic redox flow batteries (AORFBs) have gained increasing attention for large‐scale storage due to the advantages of decoupled energy and power, safe and sustainable chemistry, and tunability of the redox‐active species. Here, we report the development of a neutral‐pH AORFB assembled with a highly water‐soluble ferrocene 1,1‐disulfonic disodium salt (DS−Fc) and two viologen derivatives, 1,1'‐bis(3‐sulfonatopropyl)‐viologen (BSP−Vi) and Bis(3‐trimethylammonium)propyl viologen tetrachloride (BTMAP−Vi). Synthesized electrolytes showed excellent redox potential, good diffusion coefficient, and a good transfer rate constant. In particular, BSP−Vi has a more negative redox potential (‐0.4 V) than BTMAP−Vi (−0.3 V) and faster kinetics; therefore, it was selected to be assembled in an AORFB as anolyte, coupled with DS−Fc as catholyte.The resulting AORFB based on BTMAP−Vi/DS−Fc and BSP−Vi/DS−Fc redox couple had a high cell voltage (1.2 V and 1.3 V, respectively) and theoretical energy density (13 WhL−1 and 14 WhL−1 respectively) and was able to sustain 70 charge‐discharge cycles with energy efficiency as high as 97 %. [ABSTRACT FROM AUTHOR]

Published
2023
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45. Investigating the factors that influence resistance rise of PIM-1 membranes in nonaqueous electrolytes

Author

Massachusetts Institute of Technology. Department of Chemical Engineering, Gigli, Matteo, Kowalski, Jeffrey A, Neyhouse, Bertrand J, D'Epifanio, Alessandra, Brushett, Fikile R, Licoccia, Silvia, Massachusetts Institute of Technology. Department of Chemical Engineering, Gigli, Matteo, Kowalski, Jeffrey A, Neyhouse, Bertrand J, D'Epifanio, Alessandra, Brushett, Fikile R, and Licoccia, Silvia

Abstract

© 2019 The Authors As redox active macromolecules are introduced to the materials repertoire of redox flow batteries (RFBs), nanoporous membranes, such as polymers of intrinsic microporosity (PIMs), are emerging as a viable separation strategy. Although their selectivity has been demonstrated, PIM-based membranes suffer from time-dependent resistance rise in nonaqueous electrolytes. Here, we study this phenomenon as a function of membrane thickness, electrolyte flow rate, and solvent washing using a diagnostic flow cell configuration. We find that the rate and magnitude of resistance rise can be significantly reduced through the combination of low electrolyte flow rate and solvent prewash. Further, our results indicate that, since the increase is not associated with irreversible chemical and structural changes, the membrane performance can be recovered via ex-situ or in-situ solvent washes.

Published
2021

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