bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pulse/Pulse Reverse Electrolysis for Electrochemical Conversion Technologies
Authors: Hall Timothy , Lee Katherine , Vijapur Santosh Hanamant , Garich Holly , More Santosh R , Snyder Stephen , Inman Maria , Taylor Earl Jennings 
Published: February 2024

Faraday Technology Inc. is a research, development and electrochemical engineering firm developing electrochemical innovations based has pulse/pulse reverse electrolytic principles. [1,2] With that founding basis Faraday has been able to bridge the gap between academic understanding and small-scale demonstrations to commercialization of practical components for over 32 years of operation.
This presentation will discuss techniques where pulse/pulse reverse operation enabled improved production rates, reduced energy demand, eliminated biofouling, and enabled recycling of complex structures. We will highlight some of the key factors that determine the usefulness and successfulness of using pulse/pulse reverse principles to improve process control of the electrochemical operations. For instances, we will discuss electrochemical destruction of PFAS, electrocatalytic operations, and carbon fiber recovery from composites.

References:

J. Taylor “Adventures in Pulse/Pulse Reverse Electrolytic Processes: Explorations and Applications in Surface Finishing” J. Applied Surface Finishing,
3(4), 178-189 (2008).

J. Taylor, et al., (2019; Chapter 7) “Breaking the Chemical Paradigm in Electrochemical Engineering: Case Studies and Lessons Learned from Plating to Polishing” R.C. Alkire (Volume 18). Electrochemical Engineering: The Path from Discovery to Product.Wiley-VCH.
Lightweight and Efficient: Exploring Low-Weight Bipolar Plates for Alkaline PEM Fuel Cells
Authors: Rojo Osorio Santiago , Sanchez-Saenz Carlos Ignacio 
Published: February 2024

Alkaline proton exchange membrane (PEM) fuel cells have the potential to be highly efficient and environmentally sustainable energy sources. However, the performance and durability of these fuel cells are dependent to some extent on the bipolar plates used in their design. Bipolar plates play a crucial role in the electrochemical reactions within the fuel cell, and their design and material selection can greatly impact the efficiency and lifespan of the fuel cell.
This study focuses on three key aspects of developing efficient and durable bipolar plates for alkaline PEM fuel cells. Firstly, the study emphasizes the importance of optimizing bipolar plate design and flow field to enhance the power output and limiting current density of the fuel cell. Computational fluid dynamics (CFD) simulations are employed to optimize the flow field design, which is found to be crucial in determining the performance of the fuel cell. The optimized flow field design enhances the current density and reduces the pressure drop, resulting in improved fuel cell efficiency.
Secondly, the study investigates the potential of low-weight bipolar plates made with printed circuit boards (PCBs) as the matrix material. Traditional bipolar plates made with graphite or metal are often heavy and bulky, leading to increased material costs and decreased fuel cell efficiency. The use of PCBs as the matrix material results in a significant reduction in weight compared to traditional materials, without sacrificing performance. However, the alkaline environment in fuel cells can cause significant corrosion damage to the bipolar plates over time. To mitigate this issue, the PCBs are coated with a layer of Ni-P electroless coating to protect against corrosion.
Thirdly, the study examines the effectiveness of corrosion protection measures using Ni-P electroless coating. The electroless coating significantly improves the corrosion resistance of the bipolar plates, thereby prolonging their lifespan and maintaining the performance of the fuel cell over time. The combination of low-weight bipolar plates made with PCBs and corrosion protection measures using Ni-P electroless coating has the potential to enhance the overall performance and durability of alkaline PEM fuel cells.
Overall, this study highlights the importance of considering bipolar plate design, material selection, and corrosion protection measures in developing efficient and durable alkaline PEM fuel cells. The optimized flow field design enhances the current density and reduces the pressure drop, while the use of PCBs as the matrix material and Ni-P electroless coating as the corrosion protection measure significantly improve the fuel cell's efficiency and lifespan. These findings provide valuable insights for the development of next-generation fuel cells that are both high-performing and environmentally sustainable.
Comparative Analysis of Degradation of Pristine Nafion and Catalyst Coated Membrane Subjected to Ex-Situ Fenton's Test Approach
Authors: Patra Sudeshna , Trinke Patrick , Bensmann Boris , Hanke-Rauschenbach Richard 
Published: February 2024

Polyfluorinated sulfonic –acid ionomer membranes (e.g Nafion) are extensively used today as the benchmark materials for the electrolyte membrane in PEM water electrolysis. It is broadly accepted that the state of the health of PFSA membranes are adversely impacted by the chemical degradation occured during operation of PEMWE. The crossover gases on the catalytic surface generate Hydrogen Peroxide which is homolytically or in the presence of ferrous salts produce reactive oxygen species like hydroperoxyl (HO.) and hydroxyl (HO.) radicals. These radicals attack the ionomer subsequently leading to chain scission, unzipping and loss of functional groups and release of HF in the effluent water.
Other than Fe3+, several transition metal ions Cu2+, Ni2+, Ti3+, Cu+, can poison the membrane significantly. The fact that membrane degradation is accelerated owing to introduction of ferrous ions is fervently implemented in ex-situ degradation tests (known as Fentons tests) to evaluate the durability of membrane materials.
This work depicts a systematic investigation of degradation of pristine Nafion and catalyst coated Nafion membrane using a Fentons accelerated aging experiment. The durability of Nafion 117 and catalyst coated Nafion membrane with various counter ions against H2O2 was explored as a degradation factor of polymer electrolyte water electrolyser. Two distinct variations of the experiments were compared : (1) Nafion and CCM were dipped in only hydrogen peroxide solution, (2) Nafion and CCM were exposed to a solution containing ferrous ions and peroxide. Accelerated aging experiments were conducted over 3-7 days. The difference in degradation phenomena with and without Fe ions were evaluated in terms of the fluoride ion release. For both cases, to quantify the effect of water activity in Nafion and CCM chemical structure on both water diffusion and interfacial transport, pulse field gradient spin echo nuclear magnetic resonance (PFGSE-NMR) technique has been employed. Furthermore the equivalent weight of the Nafion and CCM can vary in presence of aforementioned chemical stressors which can be accurately quantitatively studied by confocal Raman spectroscopy. Morphological characteristic before and after aging test was also investigated. Role of H2O2 and ferous ion in mechanical behaviour of Nafion and CCM were also analyzed. The same experiment was repeated for different transition metal ions. This work sheds light on decomposition mechanism of Nafion and CCM in more detail.
Development of a High-Performance Ammonium Formate Fuel Cell
Authors: Pan Zhefei , An Liang 
Published: February 2024

Direct liquid fuel cells fueled by molecules such as methanol, ethanol and formate have received many attentions as proton exchange membrane fuel cells, primarily because of its high energy density, simple structure, small fuel cartridge, and ease storage and transport of fuels. Among them, formate, mainly referring to sodium formate or potassium formate, has drawn increasing interest due to the following advantageous characteristics: a high theoretical voltage of 1.45 V, facile and complete formate oxidation in alkaline media, and easy handle in storage and transportation. However, the cation ion (Na+ or K+) in the fuel solution does not contribute to electricity generation but only increase the extra weight load of the fuel cell system, thus lowering the energy density of formate to 2.1 kWh L-1. In this work, ammonium formate is adopted as the fuel, which not only retains the advantages of formate, but also substitutes the Na+/K+ with ammonium (NH4
+) that can be simultaneously oxidized to release electrons, i.e., electricity generation. Hence, the energy density ammonium formate is upgraded to 3.2 kWh L-1. Although promising, the development of ammonium formate fuel cell has been hindered by technical challenges related to the oxidation of ammonium formate, such as sluggish kinetics and electrode degradation. To tackle these issues, a bimetallic Pt-Pd/C electrocatalyst is synthesized by a facial chemical reduction method using sodium borohydride as agent. The Pt-Pd/C electrocatalyst exhibits better electrocatalytic activity for ammonium formate oxidation than pure Pt/C and Pd/C. Then, an ammonium formate fuel cell is developed and tested, which is composed of a Pt-Pd/C anode, a single-atom Fe/C cathode, and an anion exchange membrane (Figure 1). This fuel cell yields an open-circuit voltage (OCV) of 0.88 V and a peak power density (PPD) of 60.7 mW cm-2 at 60oC. When the hydrogen peroxide is used as oxidant, the OCV and PPD are boosted to 1.31 V and 99.6 mW cm-2, respectively. Further increasing the operating temperature to 90oC leads to a PPD of as high as 187.6 mW cm-2. In addition, a mathematical model incorporating mass/charge transport and electrochemical reactions is developed to shed light on the voltage losses and provide guidance for optimizing structural design and operating parameters.
Acknowledgement
This work was supported by a grant the Research Grants Council of the Hong Kong Special Administrative Region, China (Project No. N_PolyU559/21) and The Hong Kong Polytechnic University Centrally Funded Postdoctoral Fellowship Scheme (Project No. 1-YXAZ).
Figure 1 Schematic of an ammonium formate fuel cell.

Figure 1
PEM Water Electrolyzers: Key Enabler of the Green Energy Transition?
Authors: Carmo Marcelo , Ayers Katherine E. 
Published: February 2024

Green hydrogen generation via electrolysis is at the forefront of international debates, with an unprecedent momentum to implement hydrogen production for energy storage purposes. Various countries have already released hydrogen strategy documents, recognizing the high propositional value of hydrogen as the energy commodity of the future.
Commercial polymer electrolyte membrane (PEM) water electrolysis has reached scales of several hundred kg/day, a relevant milestone for industrial scale hydrogen generation using the PEM technology. Nevertheless, the PEM device still poses tremendous potential for continuing cost reduction, leveraging system and manufacturing scaling laws as well as advancements in nanomaterials, advanced manufacturing tools, and a circular economy for all PGM related components.
Significant improvements in some of the highest cost elements have already been achieved, including by NEL Hydrogen. Many of the technology elements such as PFSA membranes, iridium electrodes, porous transport layers, etc. are well stablished, but still need to be refined and validated in a manufacturing environment at scale, including modifications in materials and novel yet economical methods of fabrication.
This talk will describe some of the complex interactions between the elements above. We will include others such as future operating and durability/reliability requirements at scale. Finally, we will attempt to show how next generation PEM technologies will become fundamental for an ultimate energy transition based on hydrogen.
(Invited) From Electronic Conductivity Measurement to Its Role on Oxygen Electrode Delamination Phenomena: A Brief Review
Authors: Zhu Liangzhu 
Published: February 2024

Over the past few decades, degradation and stability of SOEC has been a major concern for long term applications. Numerous factors such as cell fabrication, materials selection including both cell components and metallic interconnects, operation voltage and current density, working temperatures, gas compositions, stacking techniques, etc., can all affect the stability. While seemingly it is challenging to separately identify and determine the contribution of each factor, delamination of oxygen electrode was reported as one of the main reasons for this degradation or failure [1-3]. Theoretical analyses, particularly by Anil Virkar, have shown that the actual oxygen chemical potential inside the electrolyte can be well above or below the corresponding values at the two electrodes in a SOEC when using predominantly oxygen ionic conducting membranes, leading to either delamination at oxygen electrode or electro-reduction near the fuel electrode [4-6]. Therefore, it is critical to measure electronic conductivity in the electrolytes.
Meanwhile measurement of electronic conductivity in MIEC is typically done by the classical Hebb-Wagner (H-W) polarization method[7, 8]. Over the past decades, it has been realized that the H-W method has some critical limitations or issues that may limit its accuracy or testing feasibility, such as relatively long relaxation time towards steady state, challenges on sealing, violation of true ionic blocking and possible interaction with gas phases. A few modified versions of H-W techniques and also non-H-W type techniques on electronic conductivity measurement have been reported and investigated[9-12] . In this report, a brief review is given to cover both of these topics.

References

[1] J.E. O'Brien, J.S. Herring, C.M. Stoots, G.L. Hawkes, J.J. Hartvigsen, M. Shahnam, International Journal of Hydrogen Energy, 32 (2007) 440-450.
[2] M.A. Laguna-Bercero, R. Campana, A. Larrea, J.A. Kilner, V.M. Orera, Journal of Power Sources, 196 (2011) 8942-8947.
[3] C. Graves, S.D. Ebbesen, M. Mogensen, Solid State Ionics, 192 (2011) 398-403.
[4] A.V. Virkar, Journal of Power Sources, 147 (2005) 8-31.
[5] A.V. Virkar, International Journal of Hydrogen Energy, 35 (2010) 9527-9543.
[6] A.V. Virkar, G. Tao, International Journal of Hydrogen Energy, 40 (2015) 5561-5577.
[7] M.H. Hebb, The Journal of Chemical Physics, 20 (1952) 185-185.
[8] C. Wagner, in: 7th International Conference Electrochem. Thermodyn. Kinetics, Lindau, 1955, pp. 361.
[9] X. Guo, J. Maier, Solid State Ionics, 130 (2000) 267-280.
[10] C. Chatzichristodoulou, P.V. Hendriksen, Physical Chemistry Chemical Physics, 13 (2011) 21558-21572.
[11] L. Zhu, L. Zhang, A.V. Virkar, Journal of The Electrochemical Society, 162 (2015) F298-F309.
[12] L. Zhang, L. Zhu, A.V. Virkar, Journal of Power Sources, 302 (2016) 98-106.
(Invited) Utilization of Bio-CO2 and Bio-Methane for Fuel Production: Integration Solid Oxide Electrolyzer, Low Energy Plasma Reformer with Fischer-Tropsch Synthesis
Authors: Elangovan S , Hartvigsen Joseph , Hollist Michele , Elwell Jessica 
Published: February 2024

Transition to renewable energy is essential to achieve climate protection objectives. Besides storing electricity for later use, fuel production using renewable energy is an essential part of reducing fossil dependance. Hydrogen production is receiving the greatest attention as a carbon free energy carrier with the potential to fuel future fleets of hydrogen fuel cell vehicles, to store grid electricity to accommodate asynchronous generation and load, and to a lesser extent to displace heating fuels. However, the highest value application in current markets is the production of liquid transportation fuels such as sustainable aviation fuels (SAF) and low (fossil) carbon diesel fuel. However, liquid hydrocarbon fuels only achieve the decarbonization goals if they displace fossil fuels and are produced from sustainable, ideally biogenic carbon resources.
Solid oxide electrolysis cell (SOEC) stack developed by OxEon team for MOXIE, the Mars OXygen ISRU Experiment has demonstrated the use of CO2 as an electrolysis feedstock aboard the Perseverance rover which as of this writing has operated thirteen times on Mars, splitting the Mars atmosphere CO2 to carbon monoxide and oxygen, as the first ever demonstration of In Situ Resource Utilization (ISRU) on another planet. The technology is applicable to efficient resource utilization on this world and OxEon is actively developing power to fuels technology to maximize the conversion of biogenic carbon to high value, energy dense, liquid transportation fuels that are needed by an existing vehicle fleet that will be on the road and in the air decades to come.
OxEon’s technologies are being applied to bridge the electrical and materials energy sectors. In this project OxEon processes the bio-CO2 through an SOEC and the bio-CH4 through a low energy plasma reformer. The combined synthesis gas is supplied to a Fischer-Tropsch reactor. The combination offers several advantages: the yield of biofuel nearly doubles by use of the bio-CO2 compared to the bio-methane alone, cooling the FT reactor generates all the steam needed in the SOEC system reducing the effective operating voltage (accounting for raising steam) from > 1.5 V/cell to < 1.3 V/cell, oxygen by-product from the SOEC is used in the autothermal reformer, as is some of the FT produced water. The product fuel is all bio-carbon, but it also embodies renewable electric energy in a high-value, storable and transportable liquid hydrocarbon that will be usable in the current air and ground fleets.
The Influence of Electrochemical Bias on the Exciton Dynamics of MoS2 thin Films
Authors: Samu Gergely Ferenc , Toth Peter , Sárosi Krisztina , Mogyorósi Károly , Gilicze Barnabás , Seres Imre , Bengery Zsolt , Jójárt Péter , Chikán Viktor , Janaky Csaba 
Published: February 2024

2D transition metal dichalcogenides are an attractive family of materials in the field of electronics and optoelectronics. They are excellent candidates for sensitive photodetectors, light harvesting devices (photovoltaics, photocatalysts or photoelectrodes), lasers or non-linear optical devices. All these applications rely on light-matter interactions, which processes will ultimately decide the efficiency of the derived devices. Understanding carrier dynamics and the interaction of various exotic quasi-particles (excitons, trions) in these materials is of paramount importance to design better performing devices.
Pump-probe transient absorption/reflection spectroscopy (TAS/TRS) is a powerful technique to study photophysical processes involved in charge carrier generation and recombination on the ultrafast timescale. In MoS2 photoelectrodes after light excitation different types of excitons are generated, and their decay can be monitored with these techniques. Coupling electrochemical techniques with these ultrafast methods, allows to probe the decay of the excited state in these materials under working conditions. In this manner the effect of trap state filling [1] or the effect of charge extraction [2] on the charge carrier dynamics of photoelectrochemical systems can be revealed.
In my presentation I will show ultrafast spectroelectrochemical measurements on ITO/MoS2 photoelectrodes and reveal how the decay of excitons are influenced by the applied electrochemical bias. By comparing results from TAS/TRS spectroscopy the separation of carrier dynamics on the surface and bulk of these systems can be performed. These measurements reveal that the dissociation of excitons occurs at the ITO/MoS2 interface, resulting in a long living exciton population on the surface of these samples. Charging/discharging studies carried out in these systems reveal that the trap states involved in the dissociation of excitons in these systems can be permanently filled. The electrochemical filling of these trap states allows the tuning of the excited state lifetime of these systems, which can aid the better design of photoelectrochemical devices based on MoS2.

References

[1] ACS Energy Lett. 2019, 4, 3, 702–708
[2] J. Am. Chem. Soc. 2018, 140, 1, 86–89
(Invited) Electrosynthesis of Long-Chain Hydrocarbons and Oxygenates
Authors: Yeo Boon Siang Jason 
Published: February 2024

The electroreduction of CO(2), driven by renewable electricity, can be used to sustainably generate synthetic fuels and chemical feedstocks. Long carbon chain molecules are of particular interest due to their high energy densities and utilities. However, to date, most of the CO(2) reduction products formed are limited to C2 and C3. Herein, we discuss the development of electrocatalysts for the reduction of CO(2) to long-chain oxygenates and hydrocarbons, and their underlying reaction mechanisms.
CO(2) electroreduction has been previously reported to yield a range of carbonaceous products including alcohols, hydrocarbons and carboxylic acids. Interestingly, esters, an important family of organic compounds, have not been formed. We show how C3–C6 acetate esters could be produced from CO reduction in a membrane electrode assembly (MEA) cell. The near water-free reaction environment and the high local pH in the MEA played key roles in forming the esters with a Faradaic efficiency of 22 % and a current density up to −55 mA cm−2. We also disclose that inorganic nickel oxygenate (INO)-derived electrocatalysts can reduce CO2 to linear and branched C3-C6 hydrocarbons with Faradaic efficiencies up to 6.5%. We identified Niδ+ active sites which bind CO moderately. Our results show that Ni atom polarization to be important in hindering CO poisoning of nickel and thus facilitating CO2 reduction to a wider pool of valuable products.
Finally, we show how MgAl layered double hydroxide (LDH) nanosheets ‘House-of-cards’ structures help to disperse CuO-derived Cu (OD-Cu) catalysts. The porous structures formed enhanced CO gas percolation through the catalyst layer. OD-Cu dispersed by the ‘House-of-cards’ structures catalysed CO electroreduction to C2+ products with a partial current density that is an order of magnitude higher than that shown by the unsupported OD-Cu.
References:
1) Kwon, et al. Angew. Chemie Int. Ed. 62, e202217252. 2023

2) Zhou, et al. Angew. Chemie Int. Ed. 61, e202202859. 2022.
3) Zhou, et al. Nature Catal. 5, 545. 2022.