bluuebunny/crossref_metadata_2025_split huggingface dataset:
Incorporation of Trace Metals through in situ Cation Exchange Reactions: Electrochemical and Structural Effects on Nickel Oxyhydroxide Electrocatalysts
Authors: Marquez Raul A. , Kalokowski Emma , Espinosa Michael , Bender Jay T , Son Yoon Jun , Kawashima Kenta , Chukwuneke Chikaodili E. , Smith Lettie A , Celio Hugo , Dolocan Andrei , Zhan Xun , Miller Nathan , Milliron Delia J , Resasco Joaquin , Mullins C Buddie 
Published: December 2024

Understanding how electrocatalysts evolve during operation is critical to optimizing their performance. The oxygen evolution reaction (OER) exposes electrocatalytic materials to harsh conditions that lead to significant transformations. A discovery that revolutionized OER catalysis was the dramatic improvement in activity due to the intentional, or incidental, in situ incorporation of Fe into Ni and Co oxyhydroxides. This finding raised questions about the true active phase in OER catalysts. While Fe incorporation is now widely acknowledged, there is still significant room for improvement in comprehending the in situ incorporation of trace metals and its effects on the electrochemical and structural properties of transition metal oxyhydroxides.
We report a comprehensive investigation of in situ metal incorporation on nickel oxyhydroxide OER electrocatalysts encompassing four multivalent cations: Fe, Co, Mn, and Cu. We found that adding trace amounts of these to alkaline electrolytes alters the electrocatalytic and energy storage properties of NiOxHy films. As opposed to the well-known increase in OER activity induced by Fe incorporation (Figure 1a), in situ incorporation of trace Co and Mn increases the redox capacitance (Figure 1b), while Cu incorporation does not proceed. Depth profiling measurements reveal that metal incorporation is confined to the film's surface (Figure 1c-d), resulting in an interstratified structure that partially retains the more active, disordered phase. We describe four factors determining the occurrence of in situ metal incorporation, underscoring its nature as a cation exchange reaction. Finally, Fe and Co cation exchange processes are manipulated by shifting the solubility equilibrium and through ion complexation. By providing a better understanding of in situ metal incorporation processes, our results underscore its potential as a strategy for manipulating the surface chemical composition.

Figure 1
Electrochemical Reduction of CO2 to Methane Using a Mixed Gas Feed
Authors: Sit Chun Yat , Kenis Paul J.A 
Published: December 2024

The increasing atmospheric carbon dioxide (CO2) concentration and the associated rise in global temperatures are major global concerns. One mitigation strategy being studied and employed is Carbon Capture and Storage (CCS). Another widely studied mitigation approach is Carbon Capture and Utilization (CCU), where CO2 is utilized as the feed for chemical production. The electro-reduction of CO2 (eCO2RR) is a promising technology that can convert captured CO2 to key intermediates such as carbon monoxide, methane, ethylene, and ethanol, depending on the catalyst used and its selectivity. Most eCO2RR studies use close to pure CO2 streams as the feed, whereas actual feeds at scale from direct air capture or other capture processes may not be close to 100% CO2, and may contain other contaminants.
Our work explores eCO2RR using feeds that are less than 100% CO2 but still contain substantial fractions of N2 and/or O2. Specifically, this presentation will focus on developing an electrochemical CO2 reduction approach using a mixed gas feed comprised of O2, N2, and CO2 for CH4 production. To mitigate the detrimental effects of the presence of O2 on the eCO2RR rate and selectivity, we employ an electrochemical method to remove O2 in the first step, followed by the electroreduction of CO2 to CH4 in a membrane electrode assembly cell. This two-step strategy is expected to achieve a higher selectivity for CO2 to CH4 than the direct reduction of CO2 (still in the presence of O2) to CH4. This work will also investigate the effects of cell flow pattern design, electrolyte, resilience in the presence of O2, and performance of CO2 to CH4 over multi-hour runs.
Electrocatalytic Functionalized Specialty Paper As Low-Cost Porous Transport Layer Material in CO2-Electrolysis
Authors: Stamatelos Ilias , Rentzsch Michael , Liu Chengyu , Bauer Franziska , Pasel Joachim , Barwe Stefan , Robert Marc 
Published: December 2024

Efficiently harnessing excess atmospheric carbon dioxide (CO2) is crucial for closing the carbon cycle effectively. Electrochemical CO2 reduction (ECR) holds significant promise for producing valuable products and environmentally friendly chemicals. Carbon monoxide (CO) stands out as one of the most economically viable products of ECR.[1,2] While noble metals commonly catalyze CO2-to-CO conversion, alternative non-noble catalysts are essential for cost reduction. Molecular catalysts like cobalt phthalocyanine (CoPc) offer high ECR activity but limited stability (< 10 h).[3–5] Moreover, the production cost of porous transport layers (PTLs) significantly impacts ECR electrolyzer costs, with commercial carbon-PTLs adding a 20% increase.[6–8] Our work focuses on developing low-cost, non-woven cellulose-based porous PTLs for electrochemical CO2-to-CO conversion. By depositing a cobalt phthalocyanine (CoPc) catalyst layer over our PTLs, we fabricated ECR-functioning gas-diffusion-electrodes (GDEs) for both flow-cell and zero-gap electrolyzers. Under optimal conditions, the Faradaic efficiency of CO (FECO) reached 92 % at a high current density of 200 mA cm−2. Furthering the architecture of the GDEs, CoPc was incorporated into the initial PTL slurry, forming ECR-active PTLs without the need for an additional catalyst layer. The new GDE architecture favored the CoPc-distribution by enhancing the contact and interactions with the carbon substrate and demonstrated a stable electrolysis process for over 50 h in a zero-gap electrolyzer at 200 mA cm−2 with a FECO of 80 %.[9] This study marks a substantial breakthrough in developing for the first time, paper-based functionalized PTLs for the ECR. Marking a significant contribution to the progression of the ECR into practical implications.
[1] M. Jouny, W. Luc, F. Jiao, Ind. Eng. Chem. Res. 57 (2018) 2165–2177.
[2] G.O. Larrazábal, A.J. Martín, J. Pérez-Ramírez, J. Phys. Chem. Lett. 8 (2017) 3933–3944.
[3] S. Ren, D. Joulié, D. Salvatore, K. Torbensen, M. Wang, M. Robert, C.P. Berlinguette, Science 365 (2019) 367–369.
[4] C. Costentin, S. Drouet, M. Robert, J.-M. Savéant, Science 338 (2012) 90–94.
[5] M. Wang, K. Torbensen, D. Salvatore, S. Ren, D. Joulié, F. Dumoulin, D. Mendoza, B. Lassalle-Kaiser, U. Işci, C.P. Berlinguette, M. Robert, Nat. Commun. 10 (2019) 3602.
[6] A.J. Navarro, M.A. Gómez, L. Daza, J.J. López-Cascales, Sci. Rep. 12 (2022) 4219.
[7] B. Yarar Kaplan, L. Işıkel Şanlı, S. Alkan Gürsel, J. Mater. Sci. 52 (2017) 4968–4976.
[8] R.I. Masel, Z. Liu, H. Yang, J.J. Kaczur, D. Carrillo, S. Ren, D. Salvatore, C.P. Berlinguette, Nat. Nanotechnol. 16 (2021) 118–128.
[9] I. Stamatelos, M. Rentzsch, C. Liu, F. Bauer, S. Barwe, M. Robert, ChemCatChem n/a (n.d.) e202300980.

Figure 1
(Keynote) From Electrode Development to Process Optimization: A Journey of Scaling-up CO2 Electrolysis
Authors: Janaky Csaba 
Published: December 2024

Electrochemical reduction of CO2 is a promising method for converting a greenhouse gas into value-added products, utilizing renewable energy. Novel catalysts, electrode assemblies, and cell configurations are all necessary to achieve economically appealing performance. In this talk, I am going to present a zero gap electrolyzer cell, which converts gas phase CO2 to products without the need for any liquid catholyte. I will demonstrate how multiple cells are connected into a stack, thus scaling up the electrolysis process. I will show how proper cell components and operational conditions result in industrially relevant performance. I will demonstrate the role of each component of the membrane electrode assembly, such as the catalysts, the porous transport layers, the membrane, and the ionomers.
In the second part of my talk, I will show that while precipitate formation in the cathode gas diffusion electrode is detrimental for the long-term stability, the presence of alkali metal cations at the cathode improves performance. To overcome this contradiction, I will present different approaches which help to extend the lifetime of the electrolyzer cell. I will also present a detailed electrolyte and water balance of the operational cell, to better understand the contributing factors to these phenomena. As an outlook, I will present a complex machine learning based approach, through which we aim to find the optimal operating conditions of such CO2 electrolyzer cells.
Finally, I will share the most recent insights on our containerized prototype CO2 electrolyzer system, capable of processing 100 t CO2/year.
Immobilized Molecular Catalysts for Heterogeneous Electrochemical H2 Evolution (HER) and CO2 reduction (CO2RR)
Authors: DeMonte Kieran , Bennington Michael , Marshall Aaron Timothy , Brooker Sally 
Published: December 2024

The global use of fossil fuels results in unsustainable levels of CO₂ gas being released into the atmosphere, furthering the impacts of global warming.¹ Possible capture of CO₂ from high emission processes and subsequent selective reduction (CO₂ reduction reaction, CO₂RR) to convert it into renewable fuels could move those processes towards carbon neutrality.
To move towards carbon zero, green hydrogen is a desirable alternative to fossil fuels. Hydrogen has a higher energy density and only produces water as a waste product. ‘Green’ hydrogen is produced from water using renewable energy (hydrogen evolution reaction, HER). Most hydrogen produced currently, for use in industry, is ‘grey’ hydrogen made from fossil fuels in energy intensive and carbon emitting processes, so this must also be replaced by green hydrogen.
The HER and CO2RR are energy intensive processes so catalysts are needed to reduce the energy of these chemical processes, to make them more energy and cost efficient.² The CO₂RR is a process with many possible products, highlighting the need for catalysts that can not only reduce the energy required for reduction but also produce the desired useful products selectively.
We have prepared a range of porphyrin-like dimetallic macrocyclic complexes³,⁴ and these are now being tested for electrocatalytic activity for HER and CO₂RR. This testing is being carried out under heterogenous conditions, through immobilisation of the catalysts on solid supports. This presentation will cover the synthetic steps involved in producing these macrocyclic complexes and the results of the heterogeneous electrochemical HER and CO₂RR testing on selected complexes.
1. Tollefson, J., The hard truths of climate change - by the numbers. Nature 2019, 573 (7774), 324-327.
2. Dalle, K. E.; Warnan, J.; Leung, J. J.; Reuillard, B.; Karmel, I. S.; Reisner, E., Electro- and solar-driven fuel synthesis with first row transition metal complexes. Chem. Rev. 2019, 2752-2875.
3. Li, R.; Mulder, T. A.; Beckmann, U.; Boyd, P. D. W.; Brooker, S., Dicopper(II) and dinickel(II) complexes of Schiff-base macrocycles derived from 5,5-dimethyl-1,9-diformyldipyrromethane. Inorganica Chimica Acta 2004, 357, 3360–3368.
4. Malthus, S. J.; Cameron, S. A.; Brooker, S., Improved access to 1,8-diformyl-carbazoles leads to metal-free carbazole-based [2+2] Schiff base macrocycles with strong turn-on fluorescence sensing of zinc(II) ions. Inorg. Chem. 2018, 57, 2480–2488.
Influence of Annealing Parameters on the Photoelectrochemical Performance of Spaced TiO2 Nanotubes
Authors: Son Younggon , Jung Rin , Lee Kiyoung 
Published: December 2024

Fossil fuels, currently comprising 80% of global energy consumption, are major contributors to environmental pollution due to their substantial carbon emissions. In contrast, hydrogen energy, characterized by its high energy density and zero carbon emissions, is increasingly recognized as a promising alternative energy source. Among the various hydrogen production technologies, photoelectrochemical (PEC) water splitting stands out as a leading method for generating clean hydrogen. Titanium dioxide (TiO2) is the most widely studied material for PEC hydrogen production, as it forms electron-hole pairs upon absorbing light with wavelengths shorter than 400 nm (3.0 to 3.2 eV), thereby enabling water splitting.
Crystalline TiO2 exists in three phases: anatase, rutile, and brookite, with anatase being recognized for its superior PEC properties. However, some studies have reported that mixed-phase anatase-rutile TiO2 exhibits higher PEC activity than pure anatase. Anodization is a general method for forming nanostructures to enhance the PEC efficiency of TiO2. Anodizing a titanium metal substrate in a fluoride ion-containing electrolyte produces one-dimensional nanotube structures. The length, inner diameter, and spacing of these tubes can be precisely controlled by adjusting the anodization conditions. In this study, spaced TiO2 nanotubes (SPNTs) with wide inter-tube spacing were fabricated via anodization, and their structural, physical, and PEC properties were analyzed based on annealing temperature and atmosphere. Under optimized annealing conditions, the SPNTs exhibited a mixed anatase-rutile phase, a photocurrent of 0.34 mA/cm² at 1.23 V vs RHE, and a charge transfer resistance of 556 Ω at open circuit potential.
Sweet Spot in Oxidation Temperature Enhances Conductivity and Oer Activity for IrO2-Coated SnO2 Nanofibers
Authors: Wang Shizhe , Kost Melisande , Dushimineza Felix , Döblinger Markus , Müller-Caspary Knut , Bein Thomas 
Published: December 2024

Solutions for effective energy conversion and storage are needed for the shift from fossil fuel-based, CO2-intensive energy production to a future sustainable energy-based economy. This way green energy from renewable sources, such as solar or wind power, may later be re-electrified. One option is to use water electrolysis to transform energy from renewable sources into chemical energy in the form of hydrogen. Proton Exchange Membrane (PEM) electrolysis is a potent, cutting-edge technique that leverages rare iridium-based catalysts to boost the oxygen evolution reaction (OER) to solve this issue. Reducing the total density of iridium-based catalysts for the OER requires minimizing the usage of rare and valuable iridium, which will enhance the PEM process's sustainability and economics.
Here we present an investigation aimed to further reduce the iridium usage for proton-exchange membrane (PEM) electrolysis. First, SnO2 nanofibers are produced utilizing a water-free alkoxide route. A wet-chemical method is then used to deposit nanoparticulate IrO(OH)
x
on the filaments. After subsequent oxidation at various temperatures, the final OER active catalyst is obtained.
With the emphasis on reaching high activity, stability, and conductivity at the laboratory level, ultra-small interconnected IrO
x
/IrO2 nanoparticles anchored to electrospun SnO2 nanofibers (IrO
x
/IrO2@SnO2) and associated percolation pathways are investigated. The utilization of transmission electron microscopy (TEM) in scanning mode (STEM) before and after electrocatalytic reactions provides insights into the oxidation and crystallization state of iridium oxide nanoparticles dependent on temperature and upon catalytic use. This enables an understanding of further possible reduction of iridium content by optimizing synthesis parameters. The data indicate that the optimal iridium utilization is achieved at 375°C oxidation temperature, with the highest resulting conductivity and electrochemical activity. Furthermore, TEM data reveal initiation of crystallization of IrO2 in the temperature window between 365 and 375°C. The pivotal role of conductivity in electron transport to active sites is underscored by cyclic voltammetry (CVA) measurements, which provide further insight regarding performance and stability with a view on future PEM electrolysis applications. These findings not only enhance our fundamental understanding but also offer practical strategies for advancing cost-effective and efficient electrolysis technologies.
Monitoring Water Quality in Navajo Nation Using Paper-Based Electrochemical Sensors
Authors: Billey Wayant , Platero Justin , Platero Joshua , Begay Makeiyla , Wilson Katelyn , Plummer Dallen , Nelwood Michael , Abdelazim Khaled , Soundappan Thiagarajan 
Published: December 2024

The NSF-Prem research collaborative effort between Navajo Technical University and Harvard University aims to address the critical issue of water contamination within the Navajo Nation. Through decades of uranium mining and mineral extraction has left a lasting mark on the Navajo land and groundwater resources, necessitating effective solutions. The Nana Electrochemical Analysis and Energy Storage Laboratory (NEST LAB) at NTU has developed flexible paper-based integrated with advance electrochemical techniques to detect heavy metal concentrations in water samples. These sensors are printed out of a wax printer on chromatography paper, and we manually coat eighteen sensors per sheet with carbon conductive paste to offer a cost-effective, easy to fabricate, and highly reliable, offering real-time monitoring capabilities. The project is new, and the core goal is to expedite water quality analysis and empower the Navajo community to detect potential contamination promptly. We have not yet distributed these sensors to the community to acquire hard data, but we are expecting in the future to distribute them to local chapter houses, so that residents can independently assess groundwater quality, foster a sense of ownership and proactive environmental stewardship. This partnership exemplifies the power of community-driven solutions and trains Navajo students to get involved in scientific innovations to safeguard the environment for future generations in the Navajo Nation.
Fund Support: NSF-PREM DMR-2122195 USDA-NIFA-2024-38424-41474
Sensors for Inflatable Lunar Habitat Construction
Authors: Ahn Hosang 
Published: December 2024

Lunar habitat is necessary for human exploration, especially for long duration space missions. For lunar habitat consturction, there are several other environmental hurdles to overcome than earth and constant internal pressure of habitat is added if the structure is to be inflatable.
Among these hurdles, high energetic ions and particles from solar radiation and consequence extreme temperature difference may be protected with higher priority at least to secure survival environment for humans.
In Korea Institute of Civil engineering and building Technology, new research project was launched in 2023 to design basic plan of lunar habitat construction on the moon and one of research topics is how to secure indoor environment of inflatable lunar habitat under that harsh lunar environment.
Multi layred shell structured wall was suggested from previous project and research results and was selected to the optimum initial structure to start. Multi layred shell is mainly consisted of several highly strong and heat resistant fabric such as Kevlar or Vectran in webbing with other ion or particle protective layers and thermal insulation.
Key environmental parameters for monitoring are internal air pressure, oxygen cencentration, temperature, humidity, and high energy particles by secondary radiation. Therefore, it is essential how to design and configure total sensing and monitoring system for inflatable habitat for long duration human exploration. Environmental, radiation, and inflatable structure monitoring sensors are summarized and composed to secure indoor enviroment and provide environmental quality data to HVAC system in further.
Integrating Electrokinetics with AI-Assisted Raman Spectroscopy for Bacterial Detection in Wastewater
Authors: Zhang Yirui , Herndon Liam , Padhy Punnag , Al-Zubeidi Alexander , Ogunlade Baba , Stiber Ariel , Boehm Alexandria , Dionne Jennifer 
Published: December 2024

Wastewater-based epidemiology can monitor population-level infection, provide early warnings about disease outbreaks, and help control disease spread at the community level [1,2]. However, broad-spectrum bacterial identification in wastewater presents outstanding challenges; notably, current culturing or fluorescence-based methods [3] to identify bacteria are unsuitable for real-time, high-throughput screening of diverse bacterial species, and may not work well in the complex wastewater matrix. Here, we harness electrokinetics and artificial intelligence (AI)-powered Raman spectroscopy as an innovative approach that promises the identification of a wide range of pathogenic bacteria in wastewater.
First, we synthesize gold nanorods that can electrostatically bind to bacteria surfaces, allowing for surface-enhanced Raman spectroscopy (SERS) [4] from cell surfaces. We collect SERS from bacteria spiked into filter-sterilized wastewater, including Staphylococcus aureus, Staphylococcus epidermidis, and Escherichia coli, spanning concentrations from 109 cells/mL to 104 cells/mL. Spectral clustering analysis shows that bacterial signals become less distinguishable in wastewater as the concentrations decrease. To overcome this challenge, we incorporate electrokinetic effects into SERS by employing gold microelectrodes to apply electric fields, utilizing dielectrophoresis (DEP) [5] to rapidly displace and concentrate bacteria. The four types of bacteria responded to 5-100 kHz AC fields based on their different dielectric responses and sizes, and were enriched at the microelectrode within minutes. The enrichment of bacteria is directly visualized through optical and electron microscopy, resulting in up to tenfold increases in Raman signal intensities under electrical fields at bacterial concentrations down to 104 cells/mL. Such enhancement may enable the detection sensitivity to reach environmentally relevant concentrations. Importantly, mixtures of bacteria are now distinguishable from SERS under DEP effects. Finally, employing random forest and convolutional neural network models [6], we identify biologically relevant Raman fingerprint peaks characterizing proteins, nucleic acids, and lipids from bacteria surfaces, allowing for rapid identification of bacteria species in wastewater. We also discuss integrating our method with microfluidic devices to monitor complex wastewater samples. Our method can enable generalized pathogen detection and molecular recognition in complex liquid samples, such as wastewater, blood, and seawater.
[1] Hellmér, et al. Applied and environmental microbiology. (2014).
[2] Keshaviah, et al. The Lancet Global Health. (2023).
[3] Jahn, et al. Nature Microbiology. (2022).
[4] Tadesse, et al., Nano Lett. (2020).
[5] Pethig. John Wiley & Sons (2010).
[6] Ho, et al., Nat. Comm. (2019).
(Digital Presentation) Integration of Multiple Input Multiple Output Underwater Wireless Power Transfer in a Renewable Offshore Facility
Authors: Siueia Cátia 
Published: December 2024

Hydrogen floating production storage is a promising approach to reduce the negative impacts of carbon dioxide emissions.
In this paper, we propose to investigate multiple input multiple output (MIMO) underwater wireless power transfer in a renewable offshore facility for self charging of a renewable offshore facility.
We consider a nonlinearity of the antenna to maximize the output direct current (DC) power along with radio frequency.
The results reveal that the integration of MIMO underwater wireless power transfer in a renewable offshore facility can notably reduce operation cost, additionally it can lower leakage currents, and it is safe.