bluuebunny/crossref_metadata_2025 huggingface dataset:
Novel Ion-Exchange (Blend)-Membranes Based on Free Amines for All-Vanadium Redox Flow Batteries
Authors: Stonawski Julian , Thiele Simon , Kerres Jochen Alfred
Published: September 2023

For reaching the aim of a climate-neutral EU within the European Green Deal until 2050 several new innovations in different fields, especially in the field of renewable energies, are necessary [1]. One challenge which has to be overcome is the fluctuating nature of wind and solar energy and the associated storage and release of excess energy for stabilisation of the power-grid [2]. One promising technology in this regard is the All-Vanadium Redox Flow Battery (VRFB) in which Nafion-based membranes are usually utilised [3, 4]. However, due to high costs and a low H+/V selectivity there are many attempts to find alternative materials with better performance, lower crossover and reduced costs [5, 6].

In this work we present a new aromatic, ether-free and side-chain containing polymer with free non-quaternised amine groups prepared by polyhydroxyalkylation. A new monomer was designed to improve the conductivity and morphology of the resulting membranes. The membranes show sufficient mechanical properties in the wet state and improved conductivity compared to commercially available free-amine based VRFB membranes. Blend membranes with a PBI derivative were produced to improve the mechanical properties in the dry state and the crossover of vanadium species.

The above-mentioned membranes were characterised ex-situ by using EIS, NMR spectroscopy, TGA, DMA and permeability tests. In addition, first promising in-situ characterisations were performed in a VRFB single-cell test station.

Literature

[1] European Commission: The European Green Deal, Brussels, 2019; URL: https://ec.europa.eu/info/strategy/priorities-2019-2024/european-green-deal_de#documents, accessed: 21.11.2022.

[2] Reihani, E; Motalleb, M; Ghorbani, R; Saad Saoud, L.: Load peak shaving and power smoothing of a distribution grid with high renewable energy penetration. Renewable Energy 2016, 1372 – 1379.

[3] Düerkop, D; Widdecke, H; Schilde, C; Kunz, U; Schmiemann, A.: Polymer Membranes for All-Vanadium Redox Flow Batteries: A Review. Membranes 2021.

[4] Guarnieri, M; Mattavelli, P; Petrone, G; Spagnuolo, G.: Vanadium Redox Flow Batteries: Potentials and Challenges of an Emerging Storage Technology. EEE Ind. Electron. Mag. 2016, 20 – 31.

[5] Zeng, L; Zhao, T.S; Wei, L; Jiang, H.R; Wu, M.C.: Anion exchange membranes for aqueous acid-based redox flow batteries: Current status and challenges. Applied Energy 2019, 622 – 643.

[6] Gubler, L.: Membranes and separators for redox flow batteries. Current Opinion in Electrochemistry 2019, 31 – 36.
Enhanced Electrochemical Oxygen Reduction By Modulating Electronic Structures of Platinum Nanoparticles By Nitrogen-Introduced Carbon Support
Authors: Lee Jongmin , Yoo Ji Mun , Sung Yung-Eun
Published: September 2023

With universal attention to sustainable development, the eco-friendly generation of energy has been emerging as one of the most important projects. Fuel cells, electrochemical energy conversion devices using hydrogen as the energy source, are one of the key solutions to this urgent problem. To get an effective energy conversion efficiency, understanding the reaction of fuel cells that occurred in each part is essential. Oxygen reduction reaction (ORR), which occurred in the cathode, is the main reason for reducing the efficiency because of its sluggish reaction kinetics. Therefore, it is necessary to develop highly active ORR catalysts to get efficient fuel cells. Among the various elements, platinum (Pt) has been known as the best active metal for its optimized binding properties with oxygen so plenty of research related to Pt-based materials has been reported so far. Most of them focused on electrocatalytic active material such as Pt-alloy nanocrystals or facet-controlled nanostructures where the electrochemical reaction occurred, while the surface state of the support has been largely neglected. Generally, carbon support for nanocrystals has been regarded as inert for reaction pathways on metal nanocrystals. In this study, we demonstrate that surface N-functionalization of carbon support can modulate electronic structures of supported Pt nanocrystals. Electronic structure-modified Pt nanocrystals show less affinity toward oxygen adsorption species, which means attenuated surface coverage and thereby much higher availability of Pt active sites during electrocatalysis. Consequently, reaction kinetics and mass activity are remarkably improved as much as Pt-M (M=Transition metals) alloy nanocrystals. This study will suggest the importance of surface engineering in carbon support as a factor in enhancing the electrocatalytic performance of nano-particulate electrocatalysts.
Composition-Dependent Electrocatalytic Behavior in First-Transition Metal Nanowires Toward the Oxidation of Small Organic Molecules
Authors: Noka Gesilda , Koenigsmann Christopher
Published: September 2023

Platinum-based catalysts are widely used for the electrochemical oxidation of small organic molecules (SOMs), including methanol, ethanol, and glucose. However, it has some limitations, including high cost and limited availability. Platinum’s performance is also hindered by the formation of carbon monoxide (CO) and other partially oxidized intermediates that strongly bind to the surface and hinder kinetics at low overpotentials. Binary alloys created from Pt and other more abundant transition metals aim to reduce the cost of Pt catalysts as well as alleviate the effects of the CO intermediate on Pt catalysts, thus enhancing the catalytic performance of pure Pt. In this project, we synthesize, characterize, and evaluate the electrocatalytic performance of one-dimensional electrocatalysts created from transition metal nanowires coated with precious metal catalysts. These core-shell NWs were synthesized using a template-based technique that allows for the creation of nanowires of different sizes and compositions. The nanowires were characterized using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and powder X-ray diffraction (XRD). The catalytic performance of these NWs toward SOM oxidation was evaluated in acidic conditions utilizing cyclic voltammetry and linear sweep voltammetry. We also investigate the performance of these catalysts toward the oxygen reduction reaction (ORR) utilizing rotating disk electrode measurements. The results reveal that the characteristics of the catalytic performance of the alloy NWs are dependent on their morphology and composition.
(Digital Presentation) Diagnostic Study of the Key Performance-Limiting Factors in Anion Exchange Membrane Fuel Cells
Authors: Shi Wenwen , Ding Ruimin , Liu Chang , Chen Jingchao , Han Chaoqi , Yang Jie , Lan Huiying , Huang Mengxue , Wang Qi , Yin Xi
Published: September 2023

Anion exchange membrane fuel cells (AEMFC) have received significant attention for their promised low production cost, largely enabled by the facile kinetics of the oxygen reduction reaction in alkaline electrolytes and the broader selection of potential ionomers.1,2 The performance of AEMFCs has been improved significantly by utilizing AEM with high ion exchange capacity (IEC) and optimizing membrane electrode structures.3 However, some fundamental issues limiting the performance of AEMFCs need to be better understood, especially the reaction kinetics at the catalyst-ionomer interface and the transport process at the multi-phase boundaries in the membrane electrode assembly (MEA).4,5

In this talk, we will present a systematic diagnostic study of the critical performance-limiting factors in AEMFC. We will discuss the reaction kinetics at the Pt/ionomer interface and the oxygen transport characteristics of the ionomer layer based on electrochemical data. In addition, we correlate the electrode pore structure, reaction kinetics, and mass transfer behavior with the cell performance based on the analysis of a series of MEA with varied multi-phase boundary designs. Further, experimental data will be presented with decoupled polarization behavior of both the anode and cathode of working AEMFCs. The results reveal that the deteriorated mass transport at the anode and the restricted reaction kinetic at the cathode are the crucial factors limiting the performance of AEMFC, which need to be addressed with high priority.

References

Wang, Y-J., Qiao, J., Baker, R., Zhang J. Chem. Soc. Rev., 2013, 42, 5768.

Chen, N., Hu, C., Lee, Y. M. et al., Angew. Chem. Int. Ed.
2021, 60, 7710–7718.

Huang, G., Mandal, M., Mustain, W. E., Kohl P. A. et al., J. Electrochem. Soc.
2019, 166, F637–F644.

Dekel, D. R., J. Power Sources
2018, 375, 158e169.

Jiang, H., Luo, R., Li, Y., Chen, W. EcoMat.
2022, 4, e12199.

Acknowledgement

Financial support from the National Key R&D Program of China (No. 2021YFB4001203) is greatly acknowledged.
Implications of Cation-Dependent Proton Affinity on Electrocatalytic Nitrate Reduction
Authors: Carvalho O. Quinn , Barbisan Matthew , Dawidowicz Jorin , Stoerzinger Kelsey A
Published: September 2023

Perturbation of the nitrogen cycle via Haber-Bosch nitrogen fixation and concomitant fertilizer amendment has manifested in alarmingly increased groundwater nitrate concentrations, with global human-health and ecological ramifications. Correspondingly, the denitrification of drinking water resources represents a growing area of energy consumption, though is still outpaced by the carbon-intensive Haber-Bosch process. Electrocatalytic nitrate reduction therefore offers a competitive and distributable green alternative to traditional ammonia production approaches, using renewably-sourced electrons and protons sourced from water as reducing agents without the need for added chemicals or elevated temperatures and pressures.

While considerable progress has been made in understanding the effects of electrocatalyst material parameters on nitrate reduction activity and ammonium selectivity, these studies are conducted in well-controlled and highly purified electrolytes that lack the complexity typical of expected nitrate-rich waste source streams. Recent literature on other electrocatalytic hydrogenation reactions (hydrogen evolution and carbon dioxide reduction reactions) has identified cation-dependent activity and selectivity, indicating the significance of these nominally simple ions in facilitating proton abstraction from water—of particular importance in the proton-hungry conversion of nitrate to ammonium (10 H+ per nitrate converted). Here, we investigate cation-dependent (Li+, Na+, K+) nitrate reduction activity and selectivity in (phosphate) buffered neutral electrolytes across a series of transition metals known to exhibit varying ammonium selectivities (Ag, Cu, Co). We frame our discussion of observed cation-dependent activity and selectivity within empirical literature on cation hydration free energy to understand the role of cations in mediating proton transfer during electrocatalytic hydrogenation reactions.
(Invited) Green Ammonia-Mediated CO2 Capture and Direct Electrochemical Reduction to Formate
Authors: Chen Yifu , Liu Hengzhou , Lee Jungkuk , Gu Shuang , Li Wenzhen
Published: September 2023

Direct electrochemical conversion of CO2 capture solutions (instead of gaseous CO2) into valuable chemicals can circumvent the energy-intensive CO2 regeneration and pressurization steps. While commonly used CO2 capture agents include alkali and amine solutions, ammonia has been rarely investigated. In another aspect, mismanagement of reactive nitrogen (Nr) in waste has emerged as a major problem in water pollution to our ecosystems, causing severe eutrophication and health concerns. Sustainably recovering Nr [such as nitrate (NO3
−)-N] and converting it into green ammonia (NH3) could mitigate the environmental impacts of Nr and reduce the NH3 demand from the carbon-intensive Haber-Bosch process, as well as a possible CO2 capture agent due to its alkaline nature.

In this talk, we will present our rencet research on integration of electrodialysis and electrocatalysis for ammonia synthesis from dilute waste Nr sources, and green ammonia-mediated CO2 capture (to ammonium bicarbonate, NH4HCO3) and subsequent reduction to ammonium formate (NH4HCO2) as a new approach to CO2 capture and utilization (CCU). We have demonstrated a record-high NO3
−-to-NH3 performance in a scalable, versatile, and cost-effective membrane-free alkaline electrolyzer (MFAEL): an unprecedented NH3 partial current density of 4.22 ± 0.25 A cm−2 with a faradaic efficiency of 84.5 ± 4.9%. We also discovered that an ammonium bicarbonate (NH4HCO3)-fed electrolyzer with an anion exchange membrane (AEM) outperforms the state-of-the-art KHCO3 electrolyzer with a bipolar membrane (BPM) owing to its favorable thermal decomposition property, which allows for a 3-fold increase in the in situ CO2 concentration, a maximum 23% increase in formate faradaic efficiency, and a 35% reduction in cell voltage by substituting BPM with the AEM. Our integrated process by combining NH4HCO3 electrolysis with CO2 capturing by on-site generated green ammonia from the electro-reduction of nitrate in MFAEL has shown a remarkable 99.8% utilization of CO2 capturing agent. Such a multi-purpose process may offer a sustainable route for the simultaneous removal of Nr wastes and streamlined CO2 capturing and upgrading to valuable chemicals.
(Invited) Coupling Process Driven Technoeconomic Modeling and Material Development to Chart a Commercialization Pathway for Electrochemical Nutrient Separation Technologies
Authors: Cusick Roland , Hand Steven , Li Yurui
Published: September 2023

Removal and recovery of nutrient oxyanions such as nitrate and phosphate remains challenging due to the high capital and environmental costs associated with common technologies such as reverse osmosis or ion exchange. Capacitive deionization (CDI) is a promising technology for selective ion removal due to high reported ion selectivity at dilute target ion concentrations and low operating costs. However, the impacts of material ion selectivity and influent water characteristics on CDI life cycle cost have not been considered. In this talk we present the impact of ion selectivity on CDI system cost with a parameterized process model and technoeconomic analysis framework. Simulations indicate millimolar concentration contaminants such as nitrate can be removed at costs in the range of $0.01–0.30 m-3 at reported selectivity coefficient ranges (S = 6–10). To contextualize simulated results for CDI treatment of NO3
-, CDI unit operations were sized and costed for three cases studies based on existing treatment facilities in Israel, Spain, and the United States, showing that achieving a nitrate selectivity of 10 could reduce life cycle treatment costs below $0.2 m-3 if a system lifetime of 24,000 cycles could be achieved. This talk will also discuss the inclusion of faradaic polymer coatings as a strategy to increase both target ion selectivity and electrode longevity.
(Invited) Electrochemical Routes for Nutrient Recovery from Sludge
Authors: Botte Gerardine G , Jafari Maasoomeh
Published: September 2023

A tremendous amount of waste activated sludge (WAS) is generated as a byproduct of municipal wastewater treatment plants, most of this material ends up in landfilling. The annual world generation of WAS in 2011 was 2 billion tons and it is estimated to reach 9.5 billion tons per year by 2050 [1]. WAS is a complex mixture of organic materials and nutrients such as phosphorus and nitrogen. It has been reported that more than 90% of the phosphorous and a portion of nitrogen during wastewater treatment process is transferred to the waste activated sludge. Phosphorus and nitrogen account for up to 4% and 9% of the dry sludge [2]. On the other hand, releasing these nutrients to the environment by leachate from the landfilling is a serious concern. Therefore, recovery of nutrients from WAS could address environmental concerns enforced by the increasing of WAS generation and could be accounted for as a remarkable step to circular economy.

Botte’s group has been working on electrochemical approaches to recover nutrients from sludge, E-WAS (electrochemically enhanced digesters) [3-4]. In this presentation advances in electrocatalysis in transition metal electrodes for the recovery of nutrients from sludge will be presented as well as the effect of applied cell potential, temperature, and pH.

[1] Pham TP, Kaushik R, Parshetti GK, Mahmood R, Balasubramanian R. Food waste-to-energy conversion technologies: current status and future directions. Waste Manag. (2015). Apr;38:399-408. doi: 10.1016/j.wasman.2014.12.004. Epub 2014 Dec 30. PMID: 25555663.

[2] Wei Bi, Yiyong Li, and Yongyou Hu. Recovery of phosphorus and nitrogen from alkaline hydrolysis supernatant of excess sludge by magnesium ammonium phosphate. Bioresource technology 166, (2014): 1-8.

[3] Jafari, M., Botte, G.G. Electrochemical treatment of sewage sludge and pathogen inactivation. J. Appl. Electrochem.
51, 119–130 (2021).

[4] Jafari, M., Botte, G.G. Electrochemical valorization of waste activated sludge for short-chain fatty acids production. Front. Chem.
10, (2022).
Synergistic Effect of SBA-15 Templated Mesoporous NiFe2O4 and Mxene Nanocomposite for Alkaline Hydrogen Evolution Reaction
Authors: Khalil Munawar
Published: September 2023

Hydrogen production via electrocatalytic water splitting has been considered as the most promising way to provide clean fuel for sustainable energy generation. Nevertheless, one of the challenges for such technology is the development of cheap and abundant electrocatalytic materials that can efficiently facilitate hydrogen evolution reaction (HER). Therefore, this study is aimed to investigate the synergistic effect between mesoporous NiFe2O4 (m-NiFe2O4) with high surface area of 102.4 m2/g and MXene. Here, the mesoporosity feature of NiFe2O4 was made via nanocasting method where SBA-15 was used as hard template. Meanwhile, MXene was fabricated using etching and exfoliation method. Based on the result, it was found that the integration of the two material was able to significantly improve the performance of both pristine m-NiFe2O4 and Mxene in facilitating HER in alkaline condition at 1M NaOH. This is proven by the comparative values of both onset and overpotential of the as-prepared electrocatalysts.
Synthesis of Ni-Cu Alloy Supported on Poly(phenylenediamine) As Catalysts for Hydrogen Evolution Reaction
Authors: Bouljoihel Badr , EL Attar Anas , Salhi Ouissal , Ezzahi Amine , II de Casablanca , Faculte des Universit
Published: September 2023

Finding sustainable alternatives for fossil fuels, which are responsible of the climate change is crucial. Hydrogen is a promising solution as a non-polluting fuel cell energy vector [1]. Synthetizing a new electrocatalysts is a promising approach to improve the splitting water without using high cost platinum metal [2]. In this context, several research have been conducted on alloy such as Ni-Co, Ni-Fe and Ni-Mo [3] as electrocatalyst for Hydrogen evolution reaction (HER). Herein, A simple and one step deposition method was used for the first time to synthesis a new catalyst composed of Nickel and Copper and Poly(Para-phenylediamine) for HER . A comparative study was conducted with three conjugated polymers based on Poy(phenylenediamine) [4], which were used as a support prior to the deposition of the Ni-Cu alloy by a very simple approach. The morphology and structure of the prepared catalysts were characterized by field emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD). The performance of the catalyst for the hydrogen evolution reaction was examined in alkaline medium by linear sweep voltammetry (LSV), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS).

Reference :

[1] L’ONU annonce un réchauffement climatique de 2,6°C à cause d’engagements des États “pitoyablement pas à la hauteur,” Marie Claire. (2022). https://www.marieclaire.fr/rapport-de-l-onu-sur-le-climat-vers-un-rechauffement-de-2-6-c-a-cause-d-engagements-pitoyablement-pas-a-la-hauteur-des-etats,1435999.asp (accessed January 31, 2023).

[2] I. Herraiz-Cardona, E. Ortega, J. Garcı´a Anto´n, V. Pe´rez-Herranz. Assessment of the roughness factor effect and the intrinsic catalytic activity for hydrogen evolution reaction on Ni-based electrodeposits, ª 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. https://doi.org/10.1016/j.ijhydene.2011.05.047

[3] H. Li, G. Gao, H. Zhao, W. Wang, Y. Yang, Y. Du, S. Li, Y. Liu, L. Wang, Rational design of free-standing 3D Cu-doped NiS@Ni2P/NF nanosheet arrays for hydrogen evolution reaction, International Journal of Hydrogen Energy. 46 (2021) 33078–33086. https://doi.org/10.1016/j.ijhydene.2021.07.059.

[4] S. Chemchoub, A. El Attar, L. Oularbi, S.A. Younssi, F. Bentiss, C. Jama, M. El Rhazi, Electrosynthesis of eco-friendly electrocatalyst based nickel-copper bimetallic nanoparticles supported on poly-phenylenediamine with highest current density and early ethanol oxidation onset potential, International Journal of Hydrogen Energy. 47 (2022) 39081–39096. https://doi.org/10.1016/j.ijhydene.2022.09.069.
(Digital Presentation) SOEC - Enabler of Highly Efficient Hydrogen & E-Fuel Production
Authors: Reiter Bernd
Published: September 2023

Production of green hydrogen from renewable sources shows a promising pathway for the long-term de-fossilization, now adopted by many countries in their national strategic vision. The business case hinges on widespread application in transport, stationary and industrial sectors. Cross-sectoral approach is critical, interconnection user profiles to guarantee energy security, despite intermittency. Energy efficiency of the hydrogen production process is of utmost importance to achieve hydrogen cost which are required for industry and energy applications. SOEC represents a particularly interesting technology to improve the production efficiency of hydrogen and e-fuels. This paper will discuss the technology advantages and potentials for improvement.

Keywords: SOEC, hydrogen, e-fuel, production
Electrochemical CO2 Reduction to Methyl Formate/Formic Acid in a Dual Non-Aqueous/Aqueous Flow Cell Electrolyzer
Authors: Uttarwar Sandesh , Hofsommer Dillon , Gautam Manu , Grapperhaus Craig , Spurgeon Joshua M.
Published: September 2023

Electrochemical conversion of CO2 has been very promising in neutralizing existing carbon in the atmosphere as well as creating a pathway to produce various fuels and chemicals. The use of a CO2 flow electrolyzer makes it possible to achieve high faradaic efficiencies at high current densities from pure CO2 or dilute flue gas feeds. CO2 solubility in methanol is higher than in aqueous solutions and with acidic methanol as a solvent, it is possible to generate a unique product, methyl formate. This work describes the use of mixed propylene carbonate/methanol solutions as a solvent for CO2 reduction using a gas diffusion electrode and an aqueous anolyte and optimization of a high mass flux CO2 electrolyzer to produce methyl formate using a Pb-catalyst at higher current densities. pH-dependent product distribution is also described. The partial current densities varied depending on the cell design; cells where charge passes through more solvent result in lower current density because methanol has a higher solution resistance than aqueous solutions. The methanolic catholyte is paired with an aqueous anolyte to promote a sustainable water oxidation half-reaction.
Layered Monoclinic Perrierite Oxo-Silicate La4Mn5Si4O22+Δ: A New Interstitial Oxide Ion Conductor for Low Temperature Applications
Authors: Sheikh Md Sariful , Meng Jun , Jacobs Ryan , Liu Jian , Nachlas William O. , Morgan Dane
Published: September 2023

Oxide-ion conductors are important for various energy applications such as solid oxide fuel cells, solid oxide electrolyser cells, oxygen separation membranes, oxygen sensors, etc. State-of-the-art stable oxygen active materials often have adequate oxygen ion diffusion and chemical surface exchange only at high temperatures (> 700 oC). A promising strategy to improve the oxygen ion transport is to use the interstitial oxygen ion conductors as the interstitial diffusion barriers are often lower than vacancy-mediated diffusion barrier, potentially enabling reduced operation temperatures. However, due to the large size of the oxide ion, the formation of an adequate concentration of interstitials is difficult and hence the number of interstitial oxygen conductors is currently limited to just a handful of compounds, e.g., Ruddlesden-Popper, apatite, melilite, scheelite, fluorite and disordered hexagonal perovskites.

We screened a large number of oxide materials using high-throughput ab initio methods (Please see separate poster from Jun Meng on this screening) and predicted stable formation and fast diffusion of interstitial oxygen in a new class of material La4Mn5Si4O22+δ (LMS), motivating us to synthesize this material and experimentally study its oxide ion transport properties. The room temperature X-ray diffraction study followed by Rietveld refinement confirmed its layered monoclinic perrierite structure. Electron probe micro-analysis (EPMA) and iodometric titration revealed the presence of the hyper stoichiometric oxygen anion (δ ~ + 0.5) confirming the interstitial oxygen ions within LMS lattice. Thermogravimetric analysis showed a small mass increment in LMS when heated at high temperatures suggesting the high temperature stability of interstitial oxygen ions. The measured ionic conductivity of LMS is higher than the yttria stabilized ZrO2, perovskite oxide La1-xSrxCo1-yFeyO3 and Ruddlesden-Popper oxide materials. Electrical conductivity relaxation studies demonstrated that self-diffusion and surface exchange coefficients of oxygen ion are comparable to or higher than many state-of-the-art oxide ion conductors. Finally, the high temperature stability of the synthesised material was confirmed using X-ray diffraction after each measurement.

Overall, this experimental study confirms computational predictions that layered perrierite LMS is a new class of interstitial oxide ion conductors and suggests our overall approach may help the rational design of interstitial mediated oxide ion conductors-based devices suitable for efficient and stable applications at low temperature.
(Digital Presentation) Biogenic Electrodes for Low-Temperature Solid Oxide Fuel Cells
Authors: Bhattacharjee Jyoti , Roy Subhasis
Published: September 2023

Biogenic Electrodes for Low-Temperature Solid Oxide Fuel Cells

Jyoti Bhattacharjee, Subhasis Roy*

Department of Chemical Engineering, University of Calcutta, 92 A. P. C. Road,

Kolkata-700009, India

* Email: subhasis1093@gmail.com/srchemengg@caluniv.ac.in

Abstract:

Solid oxide fuel cells (SOFCs) are potential energy-generation devices. They operate at high

temperatures, typically between 800°C-1000°C, limiting their utility. The primary challenge

in developing these fuel cells is synthesizing strong biogenic electrodes that function at low

temperatures, maintaining high performance. This experimental study examines how eco-friendly,

facile, and novel techniques for synthesis can be used to make robust, effective, and affordable

electrodes for low-temperature recyclable SOFCs (LT-SOFC). A green approach

was implemented by using biomass waste and biochar, specifically coconut shells and rice

husks, as raw materials. The synthesis comprised the hydrothermal carbonization of biomass

precursors, such as lignocellulosic nanostructures, and carbon nanotubes under controlled

conditions, followed by activation with potassium hydroxide(KOH). The resulting electrodes

had a large surface area, catalytic oxygen reduction, excellent conductivity, and sufficient

electrochemical performance. The efficacy of the biomass-derived electrodes was enhanced

by employing transition metal oxides as electrocatalysts, such as nickel oxide(NiO) and

cobalt oxide(Co3O4). The morphology and elemental composition of the electrode material

were studied using the scanning electron microscope(SEM) and energy-dispersive X-ray

spectroscopy(EDS). Electrochemical impedance spectroscopy(EIS)was used to examine the

electrochemical properties of cell electrolytes. Findings demonstrated that the hydrothermal

strategy led to the formation of homogeneous and porous electrode structures with high

galvanic activity. The biodegradable LT-SOFC stack achieved an optimal power density of

346mW/cm2 at around 550°C, indicating a substantial increase over previous experiments.

Our results have significant economic consequences for the expansion of sustainable and

renewable energy innovations in industry and nanotechnology, providing auxiliary power in

automobiles and hydrogen generation. Greenhouse gas emissions and carbon footprint can be

diminished by using biomass waste streams as feedstocks, reducing the need for fossil fuels.

The outcomes of this research provide important insights into the development, challenges,

and future possibilities of biomass-derived electrodes, and minimal temperature electrolytes

for stable SOFCs.

Keywords:

Biomass-derived; carbon footprint; electrochemical efficiency; green energy; low-temperature solid oxide fuel cells; nanotubes.
Thermodynamic Analysis of Carbon Deposition on the Fuel Electrode of a Reversible Solid Oxide Cell
Authors: Leger Jeremy Joseph , Wang Yudong , Zhou Xiao-Dong
Published: September 2023

Fouling via carbon deposition occurs in reversable solid oxide cells (RSOCs) when it operates with carbon-based fuels or performs CO2 electrolysis. Carbon deposition is known to degrade performance and, in some cases, lead to delamination and irreversible cell damage. In this study, research was conducted using thermodynamic analysis to investigate the potential of solid carbon formation during electrolysis mode by analyzing the chemical potential of electro-neutral oxygen (O2) at the interface between the electrolyte and the fuel electrode. The chemical potential of electro-neutral oxygen is calculated based on a local chemical equilibrium assumption and addresses the isothermal transport of ions and electrons across the electrolyte. The O2 chemical potential at the fuel electrode/electrolyte interface is used to evaluate the affinity of carbon deposition reactions by the corresponding Gibbs free energy changes. Our analysis shows that regardless of the chemical makeup and physical properties of a cell an oxygen chemical potential threshold is ultimately reached as applied cell voltage during electrolysis is increased which beyond this threshold carbon deposition is inevitable. Our study is expanded to include the role of fuel electrode ionic resistance on the chemical potential of O2 at the fuel electrode/electrolyte interface and shows that an increase in ionic resistance results in more favored carbon deposition. Additional findings indicate that at 800 deg. C the electrochemical reduction of carbon monoxide is thermodynamically favored at lower local CO partial pressures over the Boudouard reaction during electrolysis mode.
Revolutionizing Hydrogen Production with LSGM-Based Solid Oxide Electrolysis Cells: An Innovative Approach to Green Energy Generation
Authors: Kim Suji , Lee Sang Won , Lee Seok Hee , Kim Jong Hak , Shin Tae Ho
Published: September 2023

Solid Oxide Electrolysis Cells (SOECs) are particularly considered a promising system for generating green hydrogen, an alternative source of new energy. Many studies have been reported for the efficient production of hydrogen via SOECs, and La1-xSrxGa1-yMgyO3-δ (LSGM), a substitute for yttria-stabilized zirconia (YSZ) has emerged as a rising candidate for the electrolyte due to its superior ionic conductivity even in intermediate temperature (≤1073K). Since a cell with LSGM can work in intermediate temperatures, it can have better durability and efficiency at lower-temperature operating conditions. In this study, a SOEC concept for H2 production was studied using LSGM electrolyte support. Here we demonstrate the successful electrochemical H2 production in LSGM-based SOEC. During electrochemical electrolysis at 1073K, a current density as high as 1.15 A·cm-2 was achieved when the voltage of 1.3V was applied. Electrochemical impedance spectroscopy was also analyzed in different forms. Moreover, the faradaic efficiency of hydrogen production was calculated by collecting the hydrogen formed by the cell, which reached as high as 80%. This improved performance is attributed to the high ionic conductivity of LSGM electrolyte, even though the cell employed a 200 µm thick electrolyte support.
Efficient Decoupled Alkaline Water Electrolysis Using a Low-Cost Sodium Manganate Solid Redox Mediator
Authors: Wu Tianci , Geng Dongsheng
Published: September 2023

As an ideal energy carrier with clean, high efficiency and high energy density (142.351 kJ g-1), hydrogen is the most promising alternative to fossil fuels when it comes to decarbonizing the planet and energy supply. Today, however, the vast majority of hydrogen production occurs through fossil-fuel intensive processes which release vast amounts of CO₂ defeating the promise of decarbonizing the world. Among other hydrogen production processes, hydrogen production by electrolysis of water has broad application prospects as an alternative approach, and is very attractive for green energy development due to its advantages of cleanliness, environmental protection and zero emission.(1) Alkaline water electrolysis has dominated the current electrochemical hydrogen production industry for the past few decades, but issues such as gas product mixing and the use of renewable energy sources (e.g., solar, wind) remain inherent challenges.(2)

To this end, in this paper, low-cost Na0.44MnO2 was chosen as a solid redox mediator to decouple the evolution of H2 and O2 in alkaline conditions, which can produce high-purity gas products directly in membrane-less electrolytic cells without gas purification. As an intermediate carrier for charge storage, the decoupling efficiency can reach 97% at a constant current of 2 mA/1.5 cm2. In addition, we performed the evolutionary reactions of hydrogen and oxygen separately under intermittent renewable energy conditions to achieve direct conversion of solar to hydrogen energy, which greatly enhances the flexibility of hydrogen production and further confirms the potential practical application of Na0.44MnO2.

Figure 1. (a) CV curve of the Na0.44MnO2 electrode, and LSV curves of the Pt electrode for the HER and the RuO2/IrO2 electrode for the OER at a scan rate of 1 mV s-1 in 1M NaOH. (b) The charging/discharging curves of the Na0.44MnO2 electrode at different current densities. (c) Decoupled water electrolysis with Na0.44MnO2 electrode. (d) The stability performance of the separate H2/O2 generation at a current of 5 mA with a step time of 400 s. (e) Hydrogen purity test.

Reference

M. G. Schultz, T. Diehl, G. P. Brasseur and W. Zittel, science, 302, 624 (2003).

M. Carmo, D. L. Fritz, J. Mergel and D. Stolten, International journal of hydrogen energy, 38, 4901 (2013).
Deconvolution of Impedance Spectrums in an Anion Exchange Membrane Electrolyzer with Embedded Voltage Probes
Authors: Li Jun , Adjah-Tetteh Christabel , Wang Yudong , Zhou Xiao-Dong
Published: September 2023

High-efficient hydrogen production requires a minimized electrical work dissipation, which contributed by the resistances of all electrolyzer components during the operation. The electrochemical impedance spectroscopy (EIS) offers the understanding of resistances from different components based on their response to the alternative current frequency. However, the responses are overlapped, and it results in the highly convoluted impedance of the electrodes and limited information of the electrode processes. In this study, voltage probes are embedded in an anion exchange membrane (AEM) electrolyzer, which allow the EIS measurements of individual cell components with a three-electrode or four-electrode approach. Different metal probes made from Pt, Au and Ag are employed to separate the electrolyzer impedance. The summation of the impedances from individual cell components matches well with the total impedance of the entire cell with the error of less than 5%. Therefore, the embedded voltage probes in AEM provides a powerful platform to investigate the kinetics of HER and OER processes separately.
Electrochemistry of Selected Acetaminophen Derivatives
Authors: Mikysek Tomas , Česla Petr , Váňová Jana , Roušarová Erika , Musílek Kamil , Maliňák David , Roušar Tomáš , Ludvik Jiri
Published: September 2023

Acetaminophen (N-(4-hydroxyphenyl)acetamide, APAP) belongs to the most frequently used pharmaceuticals with analgesic and antipyretic effect [1]. The metabolization of APAP via oxidation pathway lead to formation of highly reactive intermediate N-acetyl-p-benzoquinone imine (NAPQI). It immediately reacts with a nucleophile e.g. with glutathione by formation of respective conjugate. The level of such conjugates can be directly linked to the toxicity of APAP in humans.

Hence, three derivatives of acetaminophen were synthesized and characterized [2]. In this contribution, we focus on the characterization of redox properties of selected acetaminophen derivatives (see scheme 1) which were studied by means of cyclic voltammetry, rotating-disk voltammetry and UV-VIS absorption spectrometry. The oxidation mechanism was studied in phosphate buffers of different pH as well as in non-aqueous environment of N,N-dimethylformamide The influence of substituents on the electron transfer mechanism was estimated and corresponding rate constants were evaluated. We found that the protonation/deprotonation of acetaminophen derivatives act as a rate determining steps in aqueous media. The obtained electrochemical results were accompanied by chemical ones using reaction of the conjugates with diphenylpicrylhydrazyl (DPPH radical assay) in order to examine their interaction with radical, hence radical scavenging ability.

Acknowledgement

This work was supported by the Czech Science Foundation (GA19-11867S).

References

L. O. Boreus, F. Sandberg, Acta physiologica Scandinavica
1953, 28, 261-265.

J. Vanova, D. Malinak, R. Andrys, M. Kubat, T. Mikysek, E. Rousarova, K. Musilek, T. Rousar, P. Cesla, J. Chromatogr. A
2022, 1669, 11.

Figure 1
Novel Synthetic Access to Para-Quinones Via Direct Electrochemical Oxidation
Authors: Sprang Fiona , Waldvogel Siegfried R
Published: September 2023

Equipped with unique and straightforward tunable redox properties quinones find manifold applications ranging from bio-active compounds to material science.[1] Current state of the art synthesis still resorts to stoichiometric amounts of problematic chemical oxidizing agents and noble catalysts adding to the growing environmental strain by depletion of scarce resources.[2] In order to overcome this challenge, we have developed novel and scalable protocols for the synthesis of para-quinones applicable to readily available, inexpensive phenols and benzaldehydes.[3] In advancement of previous methods, the oxidation is performed free of catalyst, mediator, or terminal oxidizing agent, effectively minimizing waste. Electricity serves as a sustainable, reagent-free oxidant and enables excellent selectivity. Effortless scalability is ensured by the development of a flow protocol, which is operable at mild, ambient conditions. The novel protocols provide quinones in yields up to 99% and possess high synthetical utility through tolerance of a wealth of functional groups, including halogens, fulfilling the prerequisite for facile late-stage modification. The scalability of the reaction was proven on a gram-scale without corrosion in yield. Moreover, the versatility of the method was demonstrated by successful extension of the protocol to generate value-added quinones from the biopolymer lignin.

Literature:

[1] a) E. J. Son, J. H. Kim, K. Kim, C. B. Park, J. Mater. Chem. A
2016, 4, 11179; b) L. A. Sazanov, Nat.
Rev. Mol. Cell Bio.
2015, 16, 375.

[2] a) R. Yoshida, K. Isozaki, T. Yokoi, N. Yasuda, K. Sadakane, T. Iwamoto, H. Takaya, M. Nakamura, Org.
Biomol. Chem.
2016, 14, 7468; 19, b) K. Omura, Synthesis
1998, 1998, 1145.

[3] F. Sprang, J. D. Herszman, S. R. Waldvogel, Green Chem.
2022, 24, 5116–5124.

Figure 1
Electrochemical and Spectroscopic Investigations of L-Glutathione with Bismuth Pharmaceuticals
Authors: Cheek Graham , Dierickx Abram
Published: September 2023

Introduction

The electrochemical and spectroscopic investigation of bismuth(III) compounds with L-cysteine has been carried out in this laboratory since our initial publication.1 Cyclic voltammetry has shown that the interaction of L-cysteine with bismuth nitrate, bismuth salicylate, and bismuth citrate increases the solubility of these compounds by complexation with L-cysteine, thereby increasing the reduction current for the bismuth complexes formed. The appearance of a UV-VIS spectroscopic band at 340 nm indicates the formation of a Bi-S bond, the sulfur being supplied by the L-cysteine. These investigations have been conducted at pH 1.00 and 3.00 to simulate conditions in the human stomach and at pH 7.40 MOPS [(3-N-morpholino)propanesulfonic acid] to simulate general physiological conditions, in particular the intestinal tract. In this presentation, continuing studies of L-glutathione, a tripeptide incorporating L-cysteine, under these conditions shall be discussed. This work is applicable to the important field of bismuth pharmaceuticals as a means of understanding the interaction of these compounds under various conditions in the human digestion system.2

Results and Discussion

Initial studies of L-glutathione with bismuth nitrate, bismuth salicylate, and bismuth citrate have been carried out under conditions similar to those of our initial work.1 It has been found that the general characteristics of the cyclic voltammograms for L-glutathione (GSH) are similar to those for L-cysteine; however, the slower rate of complexation of GSH with these bismuth compounds is evident in the changes in voltammetric features in successive sweeps. In the case of GSH addition to bismuth citrate in pH 7.4 MOPS buffer, for instance, the first sweep shows reduction of the bismuth:GSH complex at -0.71 V vs Ag/AgCl at a gold electrode, whereas a reduction process at -0.60 V is observed on the second sweep. Similar results are obtained at glassy carbon. The bismuth:GHS complex is destroyed during the reduction process as a bismuth film forms on the electrode surface. The following sweep, then, is indicative of the complexation environment in solution at that point. The bismuth ion, restored in the stripping step, apparently does not have time in the few seconds after the stripping process to fully form a complex with GSH. The observed reduction potential around -0.60 V is due to the reduction of another bismuth complex, perhaps with citrate. Further investigations are in progress to more fully describe this situation.

References

G. T. Cheek and D. Peña, J. Electrochem. Soc.,
167, 155522 (2020)

H. Li, R. Wang, and H. Sun, Acc. Chem. Res.,
52, 216 (2019).
Electrochemical Assay Validation of Cancer Biomarkers for Clinical Studies
Authors: Syed Zia , Benbrook Doris , Krishnan Sadagopan
Published: September 2023

The high mortality rate of ovarian cancer is due to the late stage of detection and development of resistance despite high initial response rates to chemotherapy in about 60-70% of patients. Hence, detailed analytical and clinical assays' validation is crucial for successful translation to clinical cancer treatment, control, and prevention. We are a team of multidisciplinary researchers focusing on an electrochemical biosensor method development and evaluation for clinically significant circulating cancer biomarkers in biofluids. Electrochemical approaches offer simplicity (analogous to the personalized glucometer), shorter assay time than traditional biological assays, high analytical sensitivity combined with biological selectivity, high reproducibility (within ±5–10% STDEV among replicates) and ultra-low detection capabilities offered by the appropriate surface designs (e.g., femtomolar and lower), smaller sample (10 µL) and reagent volumes (50 µL per sample), semi-automation (microfluidics or multichannel sample dispenser), label and label-free options, throughput designs, and direct biofluid analysis (with a moderate 2–5 fold sample dilution) for minimally invasive (e.g., serum) and noninvasive analyses (e.g., saliva, urine, sweat, and tears). This presentation will discuss our pyrenyl-nanocarbon-based electrochemical immunosensor measuring cancer protein concentrations in clinical serum solutions.
Biocompatible Surface Modification with DNA and Proteins for Carbon Electrode-Based Biosensing
Authors: Zhou Xingcheng , Furst Ariel L
Published: September 2023

Electrochemical biosensors, which combine biorecognition elements with electrochemical readout to enable sensitive and specific sensing using inexpensive, simple equipment, are a major area of research for the development of “point-of-care” (POC) diagnostics that can be utilized in low-resource settings. Commercially available screen-printed carbon electrodes (SPCEs) are often used for electrochemical biosensors due to its low cost and fabrication from abundant resources. Forming a high quality, stable, and homogenous layer of biomolecules on the carbon surface is crucial for efficient sensing; however, the chemistries used to modify carbon electrodes with biomolecules are either insufficiently specific, susceptible to stripping, or unapproachable due to over-engineering. In this talk, I describe a new, simple chemical strategy to functionalize carbon electrodes with biomolecules for the electrochemical detection of nucleic acids, enzymes, and whole cells.