bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of Supporting Pd Nanoparticles on WOx Nanorods on Their Stability and Catalytic Activity Towards the Electrochemical Oxidation of Concentrated Formic Acid
Authors: Al Najjar Taher , Soliman Alaa , El Sawy Ehab 
Published: September 2023

Direct formic acid fuel cells (DFAFC) are considered one of the most promising fuel cells to penetrate the market due to their desired and unique properties. Formic acid (FA) could be easily produced from different sources (especially biomass) and is non-toxic. The FA-based fuel cell has a high open circuit potential in comparison to methanol and Ethanol1, high energy conversion efficiency, and fast kinetics. However, the major drawback that affects using DFAFCs is the catalysts' stability and reaction intermediates' poisoning effect, especially at high concentrations of FA.
FA has a dual pathway mechanism: either the simple and desired pathway of direct oxidation to CO2
2 or the unfavorable indirect oxidation to poisonous CO-like species that strongly adsorb on the catalyst surface, deactivating it,3 before it is hardly oxidized in a second step to give CO2. Therefore, the catalyst should be designed to direct the reaction towards the direct pathway and facilitate the poisoning species removal. The most active catalyst for FA oxidation in acidic media is palladium4 but it is highly susceptible to CO poisoning, especially as the FA concentration increases due to the high contribution of the indirect pathway. In addition, palladium nanoparticles supported on carbon material are known to suffer from dissolution in the acidic media making the electrode unstable for long-term application.5

In this presentation, the synthesis of nonstoichiometric WOx nanorods using hydrothermal methods will be reported. The Pd nanoparticles are synthesized and loaded on the WOx nanorods using ethanol as both a solvent and a reducing agent to produce a surfactant-free Pd surface. The synthesized materials are evaluated using XRD, TEM, FT-IR, EDS, and XPS. The effect of WOx nanorods as catalyst support on Pd nanoparticles activity and stability towards the oxidation of different concentrations (1-4 M) of FA in acidic media are evaluated using cyclic voltammetry (CV) and chronopotentiometry (CP), and compared with that of carbon-supported Pd catalyst. The Pd behavior in both cases will be correlated to its chemical and physical properties and thoroughly discussed.

References:

J. Sun et al., RSC Adv., 8, 18619–18625 (2018).

K. Jiang, H.-X. Zhang, S. Zou, and W.-B. Cai, Phys Chem Chem Phys, 16, 20360–20376 (2014).

T. Gunji and F. Matsumoto, Inorganics, 7, 36 (2019).

A. Gharib and A. Arab, Int. J. Hydrog. Energy, 46, 3865–3875 (2021).

T. Al Najjar, N. Ahmed, and E. N. El Sawy, RSC Adv., 11, 22842–22848 (2021).
Strain Relaxation and Activity in PtCo Fuel Cell Catalyst Nanoparticles
Authors: Padgett Elliot , Holtz Megan E , Kongkanand Anusorn , Muller David A 
Published: September 2023

Interest is growing in applying fuel cells to heavy duty transportation applications, which requires the fuel cell design to prioritize efficiency and durability to provide a low lifetime cost of ownership. This motivates further development of catalysts for the oxygen reduction reaction (ORR), as ORR kinetics are a key factor in fuel cell efficiency and catalyst degradation is a major factor limiting lifetime. Pt-alloy catalysts have seen success in light-duty fuel cell applications, where they provide enhanced activity believed to originate (at least in part) from strain of the active Pt surface by the underlying Pt-alloy core. Concerns remain regarding the viability of PtCo catalysts for heavy duty applications, as they may not sustain their activity advantage over extended lifetimes and leaching of the base metal can lead to additional performance degradation. These concerns motivate investigation into the fundamental mechanisms of strain-induced activity enhancements to guide further catalyst development and understand the ultimate limits for the performance and stability of PtCo catalysts. However, practical Pt-alloy fuel cell catalysts are complex, and understanding of real strain effects in these systems remains elusive.
Here we will present an investigation into strain effects in Pt-Co ORR catalysts for fuel cells, combining scanning nanobeam electron diffraction (NBED), continuum elastic strain modelling, and full-cell electrochemistry measurements. We leverage recent developments in NBED to make high-throughput strain maps in heterogeneous, carbon-supported PtCo catalysts and identify different mechanisms of strain relaxation, including dislocations and geometric effects. Supported by continuum elastic modelling, we correlate shell thickness, strain state, and activity of PtCo catalysts. Finally, we will comment on how these results provide rational guidance to optimize stable, efficient Pt-alloy catalysts.
Atomically Dispersed Pt and Fe Sites and Pt-Fe Nanoparticles for Durable Proton Exchange Membrane Fuel Cells
Authors: Xiao Fei , Shao Minhua 
Published: September 2023

Proton exchange membrane fuel cells (PEMFCs) as a promising clean energy conversion technology have gained considerable attention. However, the high cost and low durability of Pt-based nanocatalysts for the cathodic oxygen reduction reaction (ORR) hinder the wide adoption of this technology.1 Despite great efforts on the development of advanced Pt-based catalysts to improve the Pt utilization and mass activity toward ORR, 2-3 their high activities/durability measured in liquid cells have rarely been realized in fuel cells. On the other hand, carbon-based Pt group metal (PGM)-free ORR electrocatalysts consisting of highly dispersed transition-metal single atoms in nitrogen-coordinated carbon surfaces (Me-N-C) are promising candidates to replace Pt.4 Unfortunately, the poor durability of Me-N-C has limited their practical applications.5 Some early studies6-7 shown that Me-N-C as a support for Pt-based electrocatalyst could improve the stability of the latter.
Herein, we report a hybrid electrocatalyst (denoted as Pt-Fe-N-C) consisting of Pt-Fe alloy nanoparticles on highly dispersed Pt and Fe single atoms in a nitrogen-doped carbon support (Figure 1a). The multiple types of active sites result in not only a 3.7 times higher Pt mass activity, but also excellent durability. The performance loss is negligible even after 100,000 potential cycles (Figure 1b), and no current drop is observed at 0.6 V in a fuel cell test with an ultra-low Pt loading (0.015 mgPt cm−2) in the cathode. The morphology and structure of Pt-Fe-N-C catalyst after 100,000 cycles in a fuel cell were further analyzed. Abundant single atoms were still uniformly distributed on the carbon support. No noticeable aggregation of Pt-Fe nanoparticles was observed. Most of particle size was smaller than 4 nm, a solid PtFe@Pt core-shell structure was formed. Around 7% large size particles formed a percolated structure.
This work highlights the importance of the synergistic effects among different active sites in hybrid electrocatalysts and provide an alternative way to design more active and durable low-PGM electrocatalysts for fuel cells and other electrochemical devices.
This work was supported by the Research Grant Council (HKUST C6011-20G) and Shenzhen Science and Technology Innovation Committee (SGDX2019081623340748).
Figure 1. (a) Scanning transmission electron microscope image (the spots in the blue and red dashed circles are ascribed to the Fe and Pt single atoms, respectively). (b) H2/O2 fuel cell polarization (solid symbols and left axis) and power density (hollow symbols and right axis) plots of the Pt-Fe-N-C cathode before cycling (blue) and after 100,000 potential cycles (red) between 0.6 and 0.95 V.

Figure 1
Scalable Synthesis of Highly Efficient Nife-Layered Double Hydroxides as Electrocatalyst for Water Oxidation
Authors: Seijas Da Silva Alvaro , Hartert Adrian , Oestreicher Victor , Romero Jorge , Coronado Eugenio , Lloret Segura Vicent , Abellán Gonzalo 
Published: September 2023

Oxygen evolution reaction (OER) is reckoned as the limiting step for water splitting, suffering slow kinetics (>10 000 lower than the hydrogen evolution reaction), and therefore requiring high overpotentials. Nowadays, there is a huge effort in the development of low-cost, earth-abundant, efficient, and stable electrocatalysts. Layered double hydroxides (LDHs) based on NiFe fulfil these requirements, and in addition, it possesses one of the best performances for oxygen evolution reaction (OER) in basic media reported to date.[1] LDHs exhibit a hydrotalcite-like structure composed of M(II) and M(III) cations and depict wide tunability regarding the metallic composition. However, despite their great performance, the implementation of Fe-based LDHs as electrocatalysts in real devices remains unexplored, mainly due to the current challenging synthetic approaches, incompatible with their scaling.[2] Herein we present a high clustering nanometric NiFe-LDHs obtained by a scalable synthesis. The synthetic protocol gets the opportunity to obtain ca. 100 g/L of our materials, almost two orders of magnitude bigger than the state-of-the-art synthetic approaches. Moreover, the intrinsical characteristics of this scale-up NiFe-LDH confer a better electrochemical performance than traditional synthesized NiFe-LDH in all current density ranges and different electrochemical setups from rotatory disk electrode (RDE) to Anion Exchange Membrane Water Electrolyzer (AEMWE), being tested up to a current density of 3 A·cm-2. For example the overpotential at 2.5 A·cm-2 for the scale up NiFe-LDH and Traditional synthesized NiFe-LDH samples are 1.96 V and 2.18 V, respectively (Figure 1). Interestingly, this behavior is in contrast to the recent result warning about the possibility of cell environments matching the cell performance of design catalysts.[3]

References:

[1] Yi H.; et al. Advanced Energy Materials, 2021, 11, 2002863.
[2] Zheng, Z.; Lin, L.; Mo, S.; Ou, D.; Tao, J.; Qin, R.; Fang, X.; Zheng, N. Small 2018, 14 (24), 1800759.
[3] Abellán G.; Et al. Manuscript in progress.

Figure 1
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.
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) 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).
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