bluuebunny/crossref_metadata_2025_split huggingface dataset:
Deconvoluting Soecs – One Cell at a Timeinsights from Single-Cell Analysis of Solid Oxide Electrolysis Cells at Topsoe
Authors: Padinjarethil Aiswarya , Sala Elena Marzia , Pirou Steven , Brodersen Karen , Blennow Peter Gustav , Despesse Elise , Sune Thyden Karl Tor , Tiruvalam Ramchandra , Lundegaard Lars F. , Rasmussen Søren B , Hauch Anne 
Published: December 2024

The escalating need for sustainable energy solutions has intensified research into Solid Oxide Electrolysis Cells (SOECs), a cornerstone technology in the green transition facilitating the conversion of electricity into green fuels. Topsoe has made significant strides in the field of green technologies, aiming to revolutionize the production of zero-emission fuels and chemicals, thereby contributing to global carbon emission reduction efforts.
Topsoe's commitment to leading the carbon emission reduction technologies by 2024 is demonstrated through the development of its advanced SOEC technology. This technology is central to future Power-to-X plants, providing a highly efficient electrolysis solution that complements downstream processes. The upcoming SOEC manufacturing facility in Denmark, anticipated to commence operations in 2025, epitomizes this commitment. The facility is poised to produce electrolysis cells, stacks and modules, aiming for an annual production capacity of 500 MW, with scalability prospects. Topsoe's comprehensive expertise from electrolyzers to various downstream processes enables the transformation of renewable resources into zero-emission products such as green hydrogen, green ammonia, e-Methanol, and eFuels, marking a significant step towards a sustainable future1.
The core of the work presented here entails the in-depth analysis facilitated by single-cell studies, both within Topsoe as well in close co-operation with different research institutions. Historical and ongoing research into single-cell testing, dating back several decades, has provided substantial insights into optimizing cell setup and operational parameters. These studies allow for a detailed understanding of individual cell resistance contributions, crucial for deconvoluting the impact of raw materials and manufacturing steps on the full cell performance and durability. The methodological approach includes a spectrum of techniques from in-situ characterization, such as Electrochemical Impedance Spectroscopy (EIS) and current-voltage (IV) curves, to pre- and post-mortem analyses using Scanning Electron Microscopy (SEM), Transmission Electron microscopy (TEM), Raman spectroscopy, and Energy Dispersive X-ray Spectroscopy (EDS) etc.
Such detailed single-cell level studies are pivotal in addressing the mechanical and electrochemical performance requirements of SOECs, aiming to map them to stack and system performance. Furthermore, the studies delve into the challenges of scaling up these technologies, emphasizing the importance of stress tests and impurity evaluations to enhance system lifetime and efficiency.

1.www.topsoe.com/hubfs/Investor%20Images/Annual%20Reports/Annual%20report%202023/Topsoe_AR_2023_FINAL.pdf?hsLang=en
Stabilizing the LSCF Oxygen Electrode of Solid Oxide Electrolysis Cell via Adjustment in Stoichiometry: Doping in a-Site with Ca and B-Site with Larger Cations
Authors: Karki Surendra B , Springer Renaldo , Seymour Lorraine , Le Long , Liu Tian , Ryo Sangbong , Marina Olga A 
Published: December 2024

Lanthanum strontium cobalt iron oxide (LSCF) is considered as a superior state-of-the-art oxygen electrode material for SOEC because of its high mixed ionic and electronic conductivity, superior oxygen evolution activity, compatible thermal expansion coefficient (TEC) to ceria compatible, lower reaction activation energy, and suitable sintering temperature (1000). However, LSCF suffers in performance during the long-term SOEC operation due to issues related to undesired reactivity and Sr migration. Such issues are detrimental to the electrochemical performance as they trigger the formation of multiple oxide phases, including insulating phases and electrode or barrier layer delamination. Therefore, stabilization of LSCF phase via adjustment in stoichiometry is one of the crucial strategies to develop highly stable electrodes.
In this work, several LSCF-based compositions have been synthesized by doping with size matching cation in A-site (La/Ca/Sr ratio adjustment), and doping B-site with larger cations such as Nb5+, Zr4+, and Ga3, attempting to enhance the chemical stability of LSCF and stabilize the perovskite structure. Electrical and chemical properties of these electrodes were studied using multiple characterization techniques. Electrocatalytic activity of these electrodes was evaluated in symmetric cells and in Ni-YSZ electrode-supported button cells. Structural and performance trends will be discussed in details.
Co-Electrolysis of H2O and CO2 at Intermediate Temperatures with Protonic Ceramic Cell Reactors
Authors: Li Nannan , Marousiadou Eirini , Kyriakou Vasileios 
Published: December 2024

Co-electrolysis of H2O and CO2 in protonic ceramic membrane reactors (PCMRs) is considered a promising approach to convert CO2 into value-added products, but also a way to in-situ store green hydrogen from intermediate temperature (400-600 oC) H2O electrolysis in the form of chemicals or fuels.1 In such PCMRs, steam is split (oxygen evolution reaction-OER) over the anodic electrode (positrode) while the protons created are subsequently transported through the ceramic electrolyte to the cathodic electrode (negatrode) where they react with CO2. This system exhibits significant challenges regarding the choice of the electrocatalysts’ components at both sides of the ceramic membrane. For instance, the highly oxidizing environment of the anodic steam electrolysis rules out the state-of-art Ni-based ceramometallic (cermet) electrodes, whereas the CO2 electrocatalyst environment should be appropriately tuned to achieve high selectivity to the desired products.2

Herein, we have synthesized, characterized and evaluated the performance of promising mixed ionic-(protons, oxygen ions) electronic conducting oxides (perovskites and misfit layered oxides) for use as anodes for OER. The as synthesized electrode systems were firstly characterized with several physicochemical methods (XRD, TPR, TGA, XPS) and then deposited on Ni-cermet supported half-cells for the electrocatalytic studies (EIS, LSV, CP). The results have shown that several candidate materials could allow > 80% faradaic efficiencies, while a significant number of protons reacted with CO2 towards primarily CO and less towards CH4. Interestingly, the distribution of the products showed a strong dependence on the operation temperature and current density with methane selectivity to be improved at lower operation temperatures and high current densities. The latter is practically results in higher ratios of H2/CO2 which is expected to enhance methane yields.
References

Vøllestad, R. Strandbakke, M. Tarach, D. Catalán-Martínez, M.-L. Fontaine, D. Beeaff, D. R. Clark, J. M. Serra, T. Norby;Mixed proton and electron conducting double perovskite anodes for stable and efficient tubular proton ceramic electrolysers; Nature Materials 2019, 18, 752-759.

Duan, R. Kee, H. Zhu, N. Sullivan, L. Zhu, L. Bian, D. Jennings, R. O’Hayre,“Highly efficient reversible protonic ceramic electrochemical cells for power generation and fuel production”, Nature Energy 2019, 4, 230-240.J. Martin, ChemCatChem.
Organic-Inorganic Composite Membrane Containing Low-Cost Functionalized Organosilane (FOSi) Polymer for Vanadium Redox Flow Batteries
Authors: Ajeya Kanalli Vinayak , Kim Baek Ahm , Park Sung Chul , Jung Ho-Young 
Published: December 2024

Even though the perfluorinated polymer membranes show the promising performance in various type of energy device, they are suffered from their high cost, high permeability, and difficulty in synthesis. Composite membranes prepared by adding either organic polymer or inorganic materials can reduce the amount of perfluorosulfonic acid (PFSA) and its permeability without compromising conductivity.
A new composite membrane containing low-cost and unique functionalized organosilane (FOSi) with various PFSA (long & short side chain PFSA) as a hybrid organic-inorganic composite membrane (OICM) in large-scale production has shown in this study. The OICM solution is fabricated by varying the amount of PFSA and FOSi using Roll to Roll (R2R) film casting machine. The OICM’s proton conductivity and performance are comparable to the Nafion membrane, owing to the additional hydrophilic functionalized group in the membrane. The OICM possesses high proton conductivity in the range of 0.10 to 0.135 S/cm and an ion exchange capacity in the range of 1.00 -1.45 meq/g, even though the water uptake has been lowered than the PFSA owing to better dispersion of FOSi. The prepared OICM has been used for vanadium redox flow battery (VRFB) and showed a low vanadium permeability and remarkable selectivity, which is a significant benefit. Consequently, the OICM performs comparably to Nafion in energy efficiency combined with coulombic and voltage efficiency. The unit cell with OICM has a normalized coulombic efficiency due to low permeability than PFSA and high voltage efficiency due to high proton conductivity.
In-Situ Desalination-Coupled Electrolysis with a Membrane Stack System Producing Value-Added Chemicals
Authors: Kim Byeong-ju , Park Hyunwoong 
Published: December 2024

An efficient multi-functional electrolyzer with an electrodeposited Ni- and Fe-layered double hydroxide (NiFe-LDH) anode and an electrodeposited NiMo cathode is designed for overall water splitting coupled with the desalination of saline water and production of acid and base solution. NiFe-LDH is characterized by abundant active sites for OH adsorption and an optimal binding energy for M-OH. Meanwhile, loading bimetallic NiMo on an active electrode for the HER has been known to improve the electrocatalytic activity and durability owing to its high surface area. The NiFe-LDH and NiMo pairs separated by a bipolar membrane (BPM) show overpotentials as low as those of noble metal catalysts for oxygen and hydrogen evolution reactions in 1 M KOH and 1 M H2SO4 solutions, respectively. Thereafter, the electrode pair with an array of anion- and cation-exchange membranes (AEMs and CEMs) in alternatively stacking manner showed the desalination of brackish water and seawater at specific energy consumption of 1.8 kW h m−3, with concurrent production of HCl and NaOH. The Faradaic efficiencies of the device for O2 and H2 production are >95% at J = 100 mA cm−2 over 20 h, while the initial pH values of the anolyte and catholyte remain unchanged. The proposed multi-functional electrolyzer is highly promising for converting electrical energy into hydrogen energy, simultaneously desalinating saline water, and producing value-added chemicals. Subsequently, we compared electrodialytic performance over unit cell thickness, types of ion exchange membranes, and number of stacks in the device.
This work is financially supported by Korea Water Cluster (KWC) as Korea Water Cluster ProjectLab. This work was supported by the Technology Innovation Program (or Industrial Strategic Technology Development Program-Alchemist Project) (NTIS-1415187362, 20025773, Development of building-Integrated Carbon Control Technologies) funded By the Ministry of Trade, Industry & Energy(MOTIE, Korea).
Solar Desalination Charger for Water Treatment and Value-Added Chemical Production
Authors: Kim Seonghun , Park Hyunwoong 
Published: December 2024

This study presents a photoelectrocatalytic desalination charger for remediation of aquatic pollutants and production of value-added chemicals. Under 1 sun irradiation, a Co-WBVO (BiVO4 doped with W and deposited with CoOOH) photoelectrode and aqueous NaxC electrode (Na on carbon felt, NaxC) pair efficiently desalinates brackish water (0.171 M NaCl) through ion-exchange membranes at an ion transport efficiency of ~100%. The desalted chloride is partially oxidized by photogenerated holes into reactive chlorine species (RCSs) at a Faradaic efficiency (FE) of >90%. The in-situ generated RCSs are actively involved in the sequential oxidation of As(III) and NH4
+. Meanwhile, the desalted Na+ are rapidly inserted into NaxC without any accumulation. Upon coupling with the charged NaxC, electrocatalytic production of H2O2 via O2 reduction with carbon nanotubes, H2 via H2O reduction with NiMoS, and HCOOH via CO2 reduction with porous Bi are achieved at FEs of >80%. The as-designed PEC hybrid of the proof-of-concept can be applied to various purposes, including desalination, seawater electrolysis, production of value-added chemicals, and energy storage.
Acknowledgements
This research was supported by Basic Science Research Program through the National Research Foundation of Korea(NRF) funded by the Ministry of Education(2022R1C1C2011712). This work is financially supported by Korea Water Cluster (KWC) as Korea Water Cluster ProjectLab
Triggering Catalyst-Mediated Electron Transfer for Enhanced Ion Separation in Redox-Flow Battery Desalination System
Authors: Chen Tsai-Hsuan , Tsai Shih-Kuan , Hou Chia-Hung 
Published: December 2024

Redox-flow battery desalination (FBD), an emerging electro-membrane separation technology, has garnered considerable attention due to its advantages such as continuous operation, low energy consumption, and relatively high average salt removal rate. FBD systems consist of current collectors, redox-flow electrolyte, and ion-exchange membranes (IEM) arranged in a 4-chamber structure. During operation, electron currents from the current collectors are converted into ion currents via the redox reaction of redox-active couples, such as Fe(CN)6
3− and Fe(CN)6
4−. Consequently, the ion current transported through the IEM leads to the production of diluted stream and concentrated stream in the dilute chamber and concentrate chamber, respectively.
To optimize the performance of the FBD system, enhancing the efficiency of the redox reaction is crucial. The reaction mechanism involves three steps. Taking oxidation as an example, the first step entails the transfer of Fe(CN)6
4− from the bulk solution to the surface of the current collector. Subsequently, Fe(CN)6
4− undergoes electron transfer to the electrode, forming Fe(CN)6
3−. The third step is the diffusion of Fe(CN)6
3− into the bulk solution. To shorten the path of redox couple and enhance the transportation of electron current, studies have attempted to use conductive electrode in FBD system, such as graphite felt and electrospun carbon fiber. However, limited attention has been given to the electrochemical reaction kinetics between redox couples. Hence, there is an opportunity to focus on catalyzing the redox reaction within FBD systems.
In this study, the FBD system performance were enhanced by incorporating an electrocatalyst. Nickel oxide (NiO) was chosen as the electrocatalyst and coated onto the graphite felt electrode (GF) through a hydrothermal method, resulting in the formation of the NiO-GF electrode. Electrochemical characterization conducted in Fe(CN)6
3−/4− electrolyte revealed that the NiO-GF electrode exhibited a smaller semicircle in EIS spectra and higher corresponding current in the CV loop, compared to the GF electrode. These results suggest that the NiO-GF electrode can effectively serve as a catalyst-mediated electrode in FBD process. Further investigations will be conducted to assess its performance in the FBD process, with a focus on its potential applications in high water recovery.

Figure 1
(Invited) Electrochemical Stripping for Ammonia Recovery: Mechanisms and Impacts of Chlorine Evolution
Authors: Ma Jinxing , He Jiazhou 
Published: December 2024

Electrochemical stripping is an attractive alternative to converting NH4
+ to NH3(g) via the OH− produced by the hydrogen evolution reaction at the cathode. However, conventional electrochemical systems suffer from relatively low ammonia recovery (<80%) and need of external acid solution to absorb ammonia. To address the limitations, this work has developed a novel stacked system that uses anodic oxygen evolution reaction (OER) to in−situ produce acid and achieve chemical free ammonia recovery. To solve the issue of ammonia escape caused by constant current charging in conventional electrochemical systems, pulsed electric field (PEF) has been applied to regulate side reactions and interfacial mass transfer, weakening the sweeping effect of hydrogen gas produced by the cathodic hydrogen evolution reaction on ammonia gas. With an ammonia removal rate of 35.1 g−N m−2 h−1 and an electrical energy consumption of 28.9 kWh kg−N−1, our chemical−free system in PEF mode has achieved significantly higher ammonia recovery (>90%) from high-strength streams.
With regard to a high concentration of chloride, high potentials during electrolysis may lead to the generation of strong active chlorine. The non−specific oxidation of ammonia by active chlorine results in lower ammonia recovery. This study therefore combined in−situ Raman spectroscopy to explore the effects of chloride ion concentration and pH on ammonia speciation and recovery. Under strong acidic conditions, active chlorine mainly escaped in the form of Cl2(g), thus having a negligible effect on ammonia recovery. The proposed system maintained good stability after 390 h continuous operation. While the effect of active chlorine on ammonia oxidation was negligible, the reaction of chlorine with dissolved organic matter (DOM) can form more toxic by-products. This work further realized the effective control of by-products through the integration with activated carbon adsorption process.
Overall, the total cost to recover 1 kg of NH3–N using the electrochemical system from real waste stream is $15.9, which includes $11.1 for capital expenses (CapEx) and $4.8 for operating expenses (OpEx). This highlights the great potential for realizing high ammonia recovery in practical applications, and provides insights to innovations in treatment and resource recovery.
Enhancing Charge-Transfer Performance of Titanium Electrodes through Surface Coatings for Improved Electrochemical Systems
Authors: Krall Eric , Overland Alexandra E. L. , Rivera Jesus , Ceron Maira Raquel , Hawks Steven A. 
Published: December 2024

Flow-electrode capacitive deionization (FCDI) is a promising new desalination technology. However, the commercialization of this technology faces hurdles, one of which is the lack of suitable electrode materials. Electrodes made of graphite for FCDI, while boasting excellent charge-transfer properties, are plagued by issues such as anodic oxidation, brittleness, and poor machinability. On the other hand, titanium electrodes exhibit superior durability, but suffer from poor charge-transfer performance due to self-passivation tendencies. To address this, our study aims to explore various surface coatings tailored to enhance the charge-transfer capabilities of titanium electrodes while preserving their corrosion resistance in a flow-electrode electrochemical system.
Our findings highlight the significant improvement achievable solely through surface coatings, enhancing the charge-transfer kinetics and stability of titanium electrodes. This advancement paves the way for the development of sophisticated electrochemical systems, characterized by practically ideal current collection capabilities.
Cell Design and Optimization for Efficient Hydrogen Production through Ammonia Electrolysis
Authors: Long Haowei , Paliwal Akhil , Gewirth Andrew A. , Kenis Paul J.A 
Published: December 2024

Hydrogen, pivotal for a carbon-neutral energy framework, faces hurdles in storage and transport, leading to the consideration of ammonia as a viable hydrogen carrier. Compared to hydrogen, ammonia can be liquefied at moderate temperatures and has higher energy volumetric density. Despite ammonia's potential, presently an energy-intense thermal cracking process is necessary to convert it back to hydrogen. This prompted us to explore ammonia electrolysis as a less energy intense, more sustainable alternative for ammonia-to-hydrogen process. This method promises lower theoretical energy consumption and could in principle be driven by renewable energy sources. The number of research efforts focusing on ammonia electrolysis (ammonia electro-oxidation) is limited and most frequently focuses on catalyst development to minimize poisoning and overpotentials. Studies pursuing electrolysis cell designs for ammonia oxidation are even scarcer. Our study delves into design strategies for an ammonia electrolyzer, pairing ammonia oxidation with hydrogen evolution, aiming to optimize the entire process to enhance the prospects of ammonia as a hydrogen carrier.
This presentation will compare three different designs for ammonia electrolysis: batch, flow, and membrane electrolyte assembly (MEA) cell configurations. Each cell is characterized with respect to durability and product selectivity. Ultimately, we studied multiple factors, including flow rate, ammonia concentration, pH, and different operation protocols for MEA cells. The results provide guidance toward optimal cell design and operational protocols for a high-performing ammonia electrolyzer.
BiVO4-Based Chloride Oxidation for Hypochlorous Acid (HOCl) Production, and Analysis of the Causes of Saturation Phenomenon
Authors: Kim Inho , Park Hyunwoong 
Published: December 2024

Hypochlorous acid (HOCl) is commonly used in antibacterial and disinfection treatments due to its strong oxidizing properties in aqueous solutions. Chlor-alkali process, an electrolysis method based on sodium chloride (NaCl), is the primary method for producing HOCl in industry. However, this process incurs significant energy costs, approximately 150 TWh annually, and presents dangers of environmental pollution. To address these issues and achieve environmental and economic benefits, reducing energy consumption in HOCl production using renewable energy sources such as solar power is proposed as a viable solution. Various metal oxides like TiO2, WO3, and BiVO4 have been utilized in photocatalytic systems. Among these, BiVO4 photocathodes, with a bandgap energy of around 2.4 eV, efficiently absorb a significant portion of visible light spectrum, enabling effective oxygen generation from water. However, the low value of generated oxygen (O2) prompts the development of novel photocatalytic systems from a product value perspective. Chloride oxidation reactions, instead of water oxidation, present another promising avenue in photocatalytic systems.
In this study, we easily fabricate BiVO4 electrodes via spin-coating method. We investigate the synthesis of high-value chemicals by using the oxidation of Cl- to hypochlorous acid at the anode in electrolytes containing Cl-, such as sodium chloride (NaCl) solution. Furthermore, saturation phenomena were observed during the oxidation of sodium chloride to hypochlorous acid; when the oxidation reaction persisted for over an hour, the production of hypochlorous acid reached saturation, indicating no further increase. We aim to identify and analyze the fundamental causes of this phenomenon to understand the limiting factors in this process.
Acknowledgements
This work was supported by the Technology Innovation Program (or Industrial Strategic Technology Development Program-Alchemist Project) (NTIS-1415187362, 20025773, Development of building-Integrated Carbon Control Technologies) funded By the Ministry of Trade, Industry & Energy(MOTIE, Korea)
This work is financially supported by Korea Water Cluster (KWC) as Korea Water Cluster ProjectLab