bluuebunny/crossref_metadata_2025 huggingface dataset:
(Invited) A Sustainable and Reliable Electrolyte Toward Safe Zn-MnO2 Alkaline Rechargeable Batteries
Authors: Madan Deepa , Persad Sanjay-Singh
Published: February 2024

Zinc-Manganese Dioxide (Zn-MnO2) rechargeable batteries has spurred interest due to lower cost, high specific capacity, increased safety while using in small electronic devices and wearable technology. Zn-MnO2 alkaline batteries form inactive compounds during charging and discharging that hinder their ability to be utilized in rechargeable settings. Design and development of functional electrolyte to replace traditional electrolyte have become an effective way to inhibit irreversible compound formations and Zn dendrite growth, avoid leakage issues and metallic packaging. However, many challenges such as reliable and reproducible ionic conductivity and ion transference number of free-standing electrolyte films at lower thickness (150 µm), and interfacial contact resistance between electrolyte and electrode layer still exist. Our assumption is producing reliable and consistent ionic conductivity and ion transference number of electrolytes at lower thickness (150 µm) will help in providing the faster redox reaction kinetics at electrolyte-electrode interface. Moreover, by reducing the interfacial contact resistance between electrolyte and electrode interface will help in reducing the charge transfer resistance and zincate ion movements and results in improving the reversible life cycle of batteries. Many electrolytes fabricated utilize two different solutions that are mixed separately, forming either a liquid or a solid electrolyte after curing. Due to separate mixing, both solutions are never fully incorporated into one another, causing discrepancies in the consistency of the electrolyte. Here, we propose to use sustainable chitosan, which utilized 5:1 ratio of naturally occurring Chitosan (Chi) and Polyvinyl Alcohol (PVA) respectively. The Chi and PVA solution were premixed using ultrasonic bath and vacuum suction was used to remove extra bubbles formation due to mixing of Chi and PVA. This new process of electrolyte formation was compared between different thickness (120 µm, 150 µm, and 250µm), and the best electrolyte was then compared to the old process of mixing the solutions separately for electrolyte formation. The different thickness electrolytes were soaked into Potassium Hydroxide (KOH) and compared on their Ionic Conductivity, Ionic Conductance, Ion Transference Number, PH, and Swelling Ratio. To reduce the interfacial contact resistance between electrolyte and electrode, free standing electrolyte layer will be dipped into Chi solution and then put in contact with electrodes. These electrolytes were then used in the fabrication of Zn-MnO2 batteries and measure their performance using cyclic voltammetry and galvanostatic charge-discharge.
(Invited) New Experimental and Modelling Approaches to Predict Better Corrosion and Protection Properties of Coated Metals
Authors: Terryn Herman Albert , Madelat Negin , Abdelrahman Nourhan , Dabiri Havigh Meisam , Jiryaei Zahra , Wouters Benny , Meeusen Mats , Hubin Annick , Hauffman Tom
Published: February 2024

The development of new materials is very time and material intensive. To assess the corrosion properties of coated metallic systems, typically accelerated laboratory corrosion tests are performed. Unfortunately, in the current state of the art there is no proven relationship between laboratory testing data and field performance data. This is particularly due to a lack of data from the field in which the key performance affecting properties are measured, and a lack of understanding of the mechanisms of failure and the absence of a detailed model that allows to predict the coating performance based on laboratory test data. The innovative goal of the project is to develop an integrated corrosion modelling tool that is reliable and predictive. Integrated means that all subsystems (metal, coating, electrolyte) and all phenomena leading to corrosion of the system (transport through the coating, interfacial (electro)chemistry, delamination) are brought together in one model. To achieve our goals, we need to use a combined experimental/finite element modelling (FEM) approach. The modelling is necessary for the quantitative description of all relevant phenomena. The experimental approach is necessary at two levels: on the one hand we need to perform experiments to gain mechanistic insight in the occurring phenomena and to determine input parameters for the modelling, on the other hand we need to do the experimental validation of the proposed model(s). We try to focus on both aspects bringing in new advanced combined electrochemical & in situ surface analysis, advanced finite element electrochemical modelling and more recently quantum chemical modelling. At the end of the presentation the recently started Horizon 2020 project VIPCOAT will be introduced. The goal of the EU-funded VIPCOAT project is to create an open innovation platform that should assist engineers in developing coating materials and constructing accelerated life test scenarios to assess their durability.

Acknowledgements: FWOSBO project S000718N,Predictcorr and H2020-NMBP-TO-IND-2020,Vipcoat
Efficiency of Anti-Corrosion Protective Coatings Based on Graphene Oxides Functionalised with Green Inhibitors
Authors: Linh Do Thuy , Perrin Fx
Published: February 2024

Mild steel (MS) is commonly used for infrastructure and machinery due to its various engineering properties and benefits, but they are highly prone to corrosion. For decades, organic polymeric coatings are widely applied to protect metallic systems against corrosion. Besides the physical barrier, the organic coatings have been manipulated by adding anti-corrosion pigments or corrosion inhibitors, such as red-lead or chromate to enhance protection. However, these conventional anticorrosive pigments have been substituted because of their toxicity and environmental problems. Recent studies have been consequently conducted to develop environmentally safe and green alternatives obtained from natural products.

In the framework of this study, a novel green hybrid pigment nano-pigment based on graphene oxide (GO) and an organic natural inhibitor was prepared and included in a Polyvinyl Butyral (PVB) coating. The protective properties of PVB coatings without and with the addition of GO and f-GO on steel in 3.5wt% NaCl solution were studied by electrochemical methods.

The new pigment functionalised GO (f-GO) is not only able to be an outstanding barrier, but it can also store a considerable amount of corrosion inhibitors and release them, when necessary, on the protective coating system. GO was functionalised with the green inhibitor in aqueous phase and the compound obtained was characterised by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), thermo gravimetric analysis (TGA), ultraviolet-visible spectroscopy (UV-Vis) and atomic force microscopy (AFM).

FT-IR and UV-Vis spectroscopy results indicated that the organic compound effectively reduced GO into f-GO and PVB/f-GO composite coatings showed 100 times higher anticorrosion resistance than PVB/GO and neat PVB.

Figure 1
Hydrogen Permeation Study on Zinc-Nickel Coated Ultra-High Strength Martensitic Steels
Authors: Jothi Manickam Manoj Prabhakar , Ravikumar Aravinth , Salicio-Paz Asier , Van den Bossche Bart , Höche Daniel , Lekka Maria , Rohwerder Michael
Published: February 2024

Cadmium coatings are conventionally electrodeposited on ultra-high strength steels (UHSS) used in aerospace application to provide corrosion protection. Zinc-nickel alloy coatings are being studied as an alternative to cadmium coatings as the latter exhibits environmental and health concerns. The electrodeposition of zinc-nickel alloy is accompanied by hydrogen evolution reaction, resulting in hydrogen incorporation into the coating and further inward diffusion into the steel substrate. Presence of hydrogen in UHSS leads to hydrogen embrittlement and can be detrimental to the properties. To avoid this, outgassing of the coated parts are carried out.

In this work, the diffusion of hydrogen through zinc-nickel coated and uncoated UHSS was investigated using the Kelvin-probe based detection technique. The charging of hydrogen in the samples was carried out using either an electrochemical or hydrogen gas-based charging. A comparative study between the electrochemical and gas-based charging techniques was carried out. The influence of coating morphology on the permeation was studied to understand the influence of morphology on outgassing efficiency. The diffusion coefficients were derived from multi-step permeation measurements performed by varying activity at the entry side.

This project has received funding from the Clean Sky 2 Joint Undertaking (JU) under grant agreement No 101007712. The JU receives support from the European Union’s Horizon 2020 research and innovation programme and the Clean Sky 2 JU members other than the Union.
Ti-Al-C Based MAX Phase Coating As Corrosion Protection for Ferritic Bipolar Plates
Authors: Jothi Manickam Manoj Prabhakar , Rohloff Martin , Lindemann Uwe , Kruth Angela , Rohwerder Michael
Published: February 2024

Metallic bipolar plates in fuel cells have the advantages of high electrical conductivity, low permeability to the reactants and gases, and easy manufacturability. However, resistance to corrosion under long term operation conditions limits their practical use in the fuel cell. Owing to the importance of corrosion stability, materials such as austenitic stainless steels, Ni-based alloys and coated titanium or stainless steel plates are currently being used in bipolar plates, although ferritic steels would be cost effective. A pinhole-free anticorrosion coating can help in application of the ferritic steels in fuel cells. MAX phase materials offer excellent corrosion stability and high electronic conductivity and have been successfully tested for corrosion protection of metallic bipolar plates.

In the current work, Ti-Al-C-based MAX phase coatings were prepared using high power impulse magnetron sputtering (HiPIMS). The HiPIMS process was in some cases also combined with plasma immersion ion implantation (PIII) to study the influence of the high energetic ion implantation process on the structure and performance of the resulting MAX phase layer. The deposited samples were annealed at 800 °C for 2 h in Ar atmosphere. The structure and composition of the coatings produced were studied with X-ray photoelectron spectroscopy, atom probe tomography and transmission electron microscopy. The corrosion performance of the layers was studied using a scanning flow cell coupled with inductively coupled plasma mass spectroscopy.
(Invited) On the Inhibition Mechanism of an Alkylammonium Nitrate Ionic Liquid Family on Al Alloys: Electrochemical and XPS/in Situ PM-IRRAS Studies
Authors: Gharbi Oumaïma , Méthivier Christophe , Turmine Mireille , Vivier Vincent
Published: February 2024

AA2024 are high strength Al alloys widely used in the aerospace industry due to their excellent strength to weight ratio. However, their high susceptibility to localised corrosion, caused by the presence of intermetallic particles embedded in the Al matrix, requires the use of chromate-based surface treatment formulations1. Several alternatives have been explored in the last decades, such as vanadates, chromium (III) based conversion coatings, rare-earth inhibitors or more recently, lithium containing conversion coatings2. However, these alternatives are often not versatile (cannot be transposed to all alloy systems) or are not as cost effective as chromates. Ionic liquids (ILs), usually defined as salts with a melting point below 100°C, can be considered as promising corrosion inhibitors due to their low vapour pressure, chemical and thermal stability3. In addition, they can exhibit versatile inhibition properties associated with the quasi-infinite possible anion-cation combinations3–5. In previous work, the effect of an alkylammonium nitrate IL family, namely ethylammonium nitrate (EAN), propylammonium nitrate (PAN), and butylammonium nitrate (BAN) as potential corrosion inhibitors for an AA2024-T6 Al alloy was investigated6. Electrochemical tests such as potentiodynamic polarisation and electrochemical impedance spectroscopy were performed to identify the effect of the anion and cation on the anodic and cathodic kinetics. Herein, surface analysis was performed to rationalise the electrochemical results, particularly on the reactivity of NO3
- and R-NH3
+ on the Cu-rich intermetallic particles. To this end, electrospray ionisation of EAN, BAN and NaNO3 was realised on Cu. The effect of the IL concentration and cation chain length, using PM-IRRAS (polarisation modulation -infrared reflection adsorption spectroscopy) was used to investigate molecule orientation and surface-molecule bonding as a function of surface coverage; The results provided new insights on the inhibition mechanism of this IL family.

O. Gharbi, S. Thomas, C. Smith, and N. Birbilis, Npj Mater Degrad, 2, 12 (2018) http://www.nature.com/articles/s41529-018-0034-5.

A. Kosari et al., Corros Sci, 190, 109651 (2021) https://doi.org/10.1016/j.corsci.2021.109651.

C. Verma, E. E. Ebenso, and M. A. Quraishi, J Mol Liq, 233, 403–414 (2017) http://dx.doi.org/10.1016/j.molliq.2017.02.111.

J. Sun, P. C. Howlett, D. R. MacFarlane, J. Lin, and M. Forsyth, Electrochim Acta, 54, 254–260 (2008).

N. V. Likhanova et al., Corros Sci, 52, 2088–2097 (2010) http://dx.doi.org/10.1016/j.corsci.2010.02.030.

A. Z. Benbouzid et al., Corrosion Communications, 9, 57–64 (2023).
Electrochemical Deposition of N-Heterocyclic Carbene on Steels As a Corrosion Protective Layer
Authors: Suduwella Thilini Malsha , Singh Vikram , Aloisio Mark , Ezhieh Ahmadreza Nezamzadeh , Crudden Cathleen , Mauzeroll Janine , Li Yuanjiao
Published: February 2024

Steels play a vital role in every aspect of day-to-day life. They are major components in construction,

transportation, medicine, and etc. Despite their larger usability, steels are suffering from inevitable

corrosion. Hence, finding a sustainable solution for corrosion has been a hot topic in the research field for

centuries. One extensively studied strategy is applying a protective layer on top of metals. The recent

findings show that N-heterocyclic carbene (NHC) has the potency to form a carbon-metal bond through

self-assembling1 or electrochemical deposition2 on different metals such as Au, Pt, Pd, and Ag. Herein, we

are trying to coat NHC on mild steel (MS) through electrochemical deposition to act as a corrosion

protective layer. Deposition conditions will be optimized by varying the material concentrations, applied

voltages, time durations, and substrate roughness. The NHC-coated surface is characterized by X-ray

Photoelectron Spectroscopy (XPS), Matrix-Assisted Laser Desorption/Ionization (MALDI), and Atomic

Force Microscope-Infrared Spectroscopy (AFM-IR). In addition, the contact angle measurements can be

attributed to visualizing the differences in coatings under different conditions. The corrosion studies are

utilized to understand the corrosion-resistant properties of the NHC coating. Moreover, the NHC moiety

can be modified to perform better to inhibit corrosion and improve the properties of mild steel on their

applications. Ultimately, this benchtop approach will be utilized and tested on a large scale and industrial

level.

(1) Crudden, C. M.; Horton, J. H.; Ebralidze, I. I.; Zenkina, O. V.; McLean, A. B.; Drevniok, B.; She, Z.; Kraatz,

H.-B.; Mosey, N. J.; Seki, T. Ultra stable self-assembled monolayers of N-heterocyclic carbenes on gold.

Nat. Chem.
2014, 6 (5), 409-414.

(2) Amit, E.; Dery, L.; Dery, S.; Kim, S.; Roy, A.; Hu, Q.; Gutkin, V.; Eisenberg, H.; Stein, T.; Mandler, D.

Electrochemical deposition of N-heterocyclic carbene monolayers on metal surfaces. Nat.

Commun.
2020, 11 (1), 1-10.
(Best Poster Award - 2nd Place) Energy Harvesting from CO2 Emission Exploiting an Ionic-Liquid Based Electrochemical Capacitor
Authors: Martellone Simone , Molino Davide , Zaccagnini Pietro , Pedico Alessandro , Bocchini Sergio , Ferraro Giuseppe , Lamberti Andrea
Published: February 2024

Global warming is one of the most serious problems that the humanity is facing in his history.

Since 1900 to nowadays, the global temperature has risen by 1 °C and, according to the scientific

community, the cause is related to the climate-changing emissions due to anthropogenic activities.

In order to avoid an environmental disaster, 196 countries have signed the Paris agreement that

aims to maintain global warming below 1.5 °C compared with pre-industrial levels.

The reduction of greenhouse gas emissions is a key issue in contemporary science, and in this

context, the ability of certain ionic liquids (ILs) to capture carbon dioxide has attracted a lot of

interest. The idea presented in this work is to design an electric double layer supercapacitor which

is able to harvest energy by exploiting the reaction between an ionic liquid and carbon dioxide. In

particular, the system consists of two carbon-based electrodes and a polymeric separator soaked

in ionic liquid. The use of carbon electrodes ensures a high surface area and excellent electrical

conductivity while imidazole-based ionic liquid acts and as electrolyte and as capture media.

The operating principle of this system is a novel mechanism which exploits the formation of a

voltage drop across the device when the electrode-IL interfaces are different; the two different

interfaces are ensured by the presence of imidazole carbamate in a part of the cell (Im − CO2

reaction’s product) and just imidazole in the other part.

Unfortunately the high viscosity of ionic liquids affects a lot the carrier transport and consequently

the device’s performance too; this aspect worsens when imidazole reacts with CO2. Improved ion

mobility is achieved by reducing the ion pairing through the use of high dielectric solvents capable

to screen the ions’ electric field. Polar aprotic solvents tend to have large dipoles making them

suitable for the solvation of charged species.

Several mixtures have been analyzed to detect the best dilution which guarantees high ionic mobility

still maintaining a large amount of active species.

A further performance improvement has been achieved through the engineering of the electrodes,

namely the capacitance of the supercapacitor has been enhanced by exploiting the huge specific

surface area of the activated carbon.

The results show that all the upgrades mentioned lead to an improvement of 500 times in terms of

harvested energy.

Acknowledgement: This result is part of a project that has received funding from the European Research Council

(ERC) under the European Union’s ERC Starting Grant Grant agreement No. 949916

Figure 1
(Invited) Contribution of Oxygen Reduction to Mg Corrosion: Computational Modelling
Authors: Höche Daniel , Wang Cheng , Xu Wen , Zheludkevich Mikhail , Lamaka Sviatlana
Published: February 2024

The magnesium corrosion mechanisms are still a matter of discussions. Independent from that there is agreement that the cathodic behaviour is based on the superposition of water and oxygen reduction reactions [1]. Accessing the amount of cathodic reaction contributions to the entire corrosion current density via experiment is challenging [2,3]. In a recent work of Wang et al. [4] a combined experimental and computational approach was utilized to explore the superposition of cathodic reactions during Mg corrosion in aqueous electrolytes for different iron impurity situations. The study shows significant variation of percentual contribution of oxygen reduction to the cathodic current for the studied purity levels.

In this work a computational modelling approach is presented accordingly. It is based on the numerical model developed by Höche [5] and enables virtual local electrochemical testing and computational assessment of (electro-)chemical system and transport descriptors. Respective simulation results show, how corrosion and testing system parameters change the measured oxygen approach curves. Subsequently a multi-parameter calibration enabled the quantification of oxygen reduction reaction to the entire corrosion process. The reproduction of experimental results and strategies for model improvement are discussed.

REFERENCES:

[1] Höche, D., Blawert, C., Lamaka, S. V., Scharnagl, N., Mendis, C., & Zheludkevich, M. L., The effect of iron re-deposition on the corrosion of impurity-containing magnesium. Physical Chemistry Chemical Physics, 18-2 (2016), 1279-1291.

[2] Yasakau, K. A., Höche, D., Lamaka, S. L., Ferreira, M. G., & Zheludkevich, M. L., Kelvin microprobe analytics on iron-enriched corroded magnesium surface. Corrosion, 73-55 (2017), 583-595.

[3] E.L. Silva, S.V. Lamaka, D. Mei, M.L. Zheludkevich, The Reduction of Dissolved Oxygen During Magnesium Corrosion, ChemistryOpen, 7 (2018) 664-668.

[4] C. Wang, W. Xu, D. Höche, M.L. Zheludkevich, S.V. Lamaka, Exploring the contribution of oxygen reduction reaction to Mg corrosion by modeling assisted local analysis, Journal of Magnesium and Alloys, 11 (2023) 100-109.

[5] Höche D., Simulation of corrosion product deposit layer growth on bare magnesium galvanically coupled to aluminum. Journal of the electrochemical society, 162-1 (2014), C1.

ACKNOWLEDGEMENTS: C. Wang, W. Xu, thank China Scholarship Council for the funding, grants no. 201806310128 and 201908510177
(Invited)
In-situ Evaluation of Brass Dezincification Corrosion Under Galvanostatic Polarization Combined with Video Observation
Authors: Hoshi Yoshinao , Otake Yoshiyuki , Kito Kaito
Published: February 2024

Brass is widely used as the applications involving water supply pipes and pipe heat exchangers owing to its good mechanical properties. One of the limiting factors for use of brass is the dezincification corrosion, which may cause the water leakage accident. In the dezincification corrosion, the selective dissolution of zinctakes place on the brass surface, and the porous copper rich layer is formed on the brass surface1,2. To clarify the dezincification corrosion behavior of brass, we have newly developed a real-time cross-sectional surface observation system to examine the dezincification corrosion behavior of brass6. Our group developed a real-time surface observation system combined with video imaging to investigate the dissolution behavior of metals3-5. Comparing to the previous works3-5, the developed system in the present study allows for an in-situ monitoring of metal or alloy cross-section during electrochemical measurement because the video of metal or alloy cross-section can be taken by an optical microscope combined with a charge-coupled device camera. We applied the developed method for the investigation of brass dezincification corrosion, demonstrating that the inhomogeneous dissolution was observed in the depth direction under galvanostatic polarization. The average erosion depth could be estimated from the cross-sectional surface images at each measurement time. The results indicated that the depth erosion rate was different at initial and later stages, implying the preferential dissolution of zinc or the simultaneous dissolution of zinc and copper on the brass surface. Based on the video images and potential changes of brass during the measurement, the detailed dissolution behavior was discussed in the present study.

References

H.W. Pickering, C. Wagner, J. Electrochem. Soc., 7, 114 (1967).

Y. Hoshi et al., J Solid State Electrochem, 19, 3551 (2015).

Y. Hoshi et al., J. Electrochem. Soc., 164, C450 (2017).

Y. Hoshi et al., Surf. Finish. Soc. Jpn., 69, 34 (2018).

Y. Hoshi et al., J. Electrochem. Soc., 165, C243 (2018).

Y. Hoshi et al., Mater. Trans., 64, 885 (2023).
Estimation of State-of-Charge and Energy Efficiency of Supercapacitors Using a 1-D Electrochemical Model
Authors: Saha Pankaj , Ali Abdul , Ramadesigan Venkatasailanathan
Published: February 2024

Supercapacitors (SCs) have found a broad application spectrum due to their unique characteristics, including high power density and long cycle life [1]. Supercapacitors have been extensively studied to be used with Li-ion batteries for electric vehicle applications due to their complementary characteristics [1]. The energy management system of these applications relies on accurate information about the state-of-charge (SOC) and energy efficiency of the storage device at the cell level for effective monitoring and control. In the case of SCs, coulomb counting is the most commonly used SOC identification method; however, it entails certain challenges, including initial SOC information, effects of leakage current, and measurement noise [1]. Alongside improving the capacitive health diagnosis, it is critical to identify utilizable capacitance. During rapid charge/discharge of an SC, the ions in the electrolyte are immediately adsorbed/desorbed within the macro-pores, which leads to achieving the desired terminal voltage level instantaneously. However, this hinders ions’ penetration in the micropores, causing an inhomogeneous distribution of the ions across the electrodes, increasing the electrolyte resistance, resulting in poor utilizable capacitance and a drop in its energy efficiency [2]. Derived from a one-dimensional model [2, 3], a simplified SOC and energy efficiency estimation scheme of the SCs is proposed in this study. In the solid phases, the charge density of the SC is approximated as a function of its electrodes’ specific surface area, double-layer differential capacitance, and the potential drop across the double-layer. The SOC of the SCs can be expressed as a function of the solid phase charge density in the positive electrode or negative electrode, as defined in Eqn. (1). The energy efficiency (Eeff
) of the SCs can be expressed as a function of the ratio of bulk double-layer potential difference of the electrodes to the output terminal voltage change, as defined in Eqn. (2).

SOC(t)=(ρ(t)/ρmax)×100 ...............(1);

Eeff=(ΔΦ/ΔΦd/ΔV)×CrΔV2/2 ..............(2)

where ρ and ρmax are the electrode charge density at t time and a fully charged state, respectively; ΔΦd
is the bulk double-layer potential difference; ΔV is the terminal voltage change; and Cr
is the rated capacitance.

The electrochemical model is used to analyze the effectiveness of the proposed SOC and energy efficiency model considering a galvanostatic charge and discharge. In this limited scope, a concise response of the model compared to their respective standard methods is shown in Fig. 1. A SAFT 3500 F SC cell parameters are considered to perform the simulations [2, 3]. The results show that the SOC estimation scheme identifies the remaining charge without considering the initial SOC information. Similarly, the energy efficiency model calculates the energy received/delivered by the SC effectively.

Figure 1
Constructing a Robotic Platform for the Autonomous Design of High-Entropy Electrolytes
Authors: Fisker-Bødker Nis , Vincent Smobin , Martinez Victor , Chang Jin Hyun , Vegge Tejs
Published: February 2024

The use of machine learning and robotics in laboratory experiments has seen a rapid increase in recent years, driven by the need for more accurate and efficient experimental results.

Despite strong synergies when combined with machine learning models, autonomous robotics hardware for electrochemical experiments has not received the same spotlight. In this work, we introduce a customizable robotic platform designed for the electrochemical characterization of liquid battery electrolytes. The platform is applicable for synthesizing and characterizing a large number of samples with varying compositions and can be used in connection with machine learning algorithms for performance optimization.

We discuss the challenges associated with working with a robotic platform compared to other solutions, demonstrate design considerations on test cells for <1 ppm O2 atmosphere, and how to design a heating/cooling system. A brief overview of different fabrication methods and tools for developing the robotic setup is offered. We present a hardware control solution that allows for the future addition of hardware like pumps and sensors and show how to integrate these components while keeping a tight code design. Finally, we demonstrate the importance of accurately monitoring the uncertainties for the included components and their implications on the training accuracy of the machine learning model.

Overall, our work presents a promising approach to electrochemical synthesis and characterization that has the potential to improve the efficiency and accuracy of experimental results.
Ammonia as an Energy Carrier for Renewable Energy Conversion and Storage
Authors: Liu Yun , Pan Zhefei , LIU Yun
Published: February 2024

An emerging energy carrier, ammonia (NH3), has attracted ever-increasing attention due to its high hydrogen content (17.65 wt. %) and its ease of storage, transportation, and handling [1,2]. This work aims to investigate the feasibility of utilizing ammonia as an energy carrier for intermittent renewable energy conversion and storage via an electrochemical flow cell, which includes two independent electrocatalytic processes (Fig. 1): ammonia production via nitrogen reduction and electricity generation via ammonia oxidation [3,4]. Firstly, the effects of structural design and operating parameters on the flow cell performance are investigated. Our preliminary results have shown that the ammonia yield reaches 27.9 μg h−1 mg−1 and the power density reaches 20.7 mW cm-2. Secondly, an in-depth analysis and discussion on the simultaneous transport of mass and charge through the flow cell are conducted. Thirdly, a techno-economic assessment for using ammonia as an energy carrier is performed. These research findings will provide crucial insights into the utilization of ammonia as an energy carrier for renewable energy conversion and storage.

Acknowledgement

This work was fully supported by a grant from the National Natural Science Foundation of China (Project No. 52022003)

References

[1] Y. Zhao, B.P. Setzler, J. Wang, J. Nash, T. Wang, B. Xu, Y. Yan, An efficient direct ammonia fuel cell for affordable carbon-neutral transportation, Joule, 3 (2019) 2472–2484.

[2] Y. Guo, Z. Pan, L. An, Carbon-free sustainable energy technology: Direct ammonia fuel cells, J. Power Sources, 476 (2020) 228454.

[3] Y. Liu, Z. Pan, O.C. Esan, X. Xu, L. An, Performance characteristics of a direct ammonia fuel cell with an anion exchange membrane, Energy Fuels, 36 (2022) 13203-13211.

[4] Y. Liu, Z. Pan, O.C. Esan, X. Liu, H. Wang, L. An, Efficient electrocatalytic nitrogen reduction to ammonia with FeNi-Co/carbon mat electrodes, J. Alloys Compd, 927 (2022) 166973.

Figure 1. Ammonia as an energy carrier for renewable energy conversion and storage.

Figure 1
(Invited) Plasma-Thermal Assisted Design of Smart Hybrid Carbon/Metal Sulfide Electrodes
Authors: Marath Santhosh Neelakandan , Zavašnik Janez , Cvelbar Uros
Published: February 2024

The spontaneous increase for advanced energy materials to meet consumer requirements demands the designing of smart, high-performing materials for fabricating next-generation energy devices. The requirement is not only for smart materials but also for manufacturing alternative devices to the rapidly exhausting lithium-based batteries. Currently, sodium-based metal-ion batteries (SIBs) emerged as an alternative to lithium batteries, which also require novel designs of electrodes for achieving high performance. Bridging the gap between theory and realization in SIB development is a significant challenge. A combination of carbon and metal sulfides has been widely reported as a promising electrode structure for SIBs. However, the performance, durability and processing time of such structures have to be improved for practical applications. Considering the importance of electrode designing for battery systems, plasma and thermal processing techniques have been employed to create advanced smart hybrid materials for high-performing SIBs. Plasma produces vertical carbon nanofibers (VCN) directly on a conductive substrate and anchors them with molybdenum. Later, thermal processing was employed to convert them to corresponding metal sulfides. Such designed binder-free composite anode consisting of vertical carbon nanofiber/molybdenum sulfide (VCN/MoS2) nanostructures. The vertically aligned morphology of the binder-free VCN/MoS2 hybrid composites facilitates electrolyte penetration and shortens ion diffusion channels. The direct contact between the VCN to the current collector improves ion/electron conductivity for the electrode. These advantageous features enable the binder-free VCN/MoS2 hybrid composite electrodes to exhibit superior electrochemical properties when used as an anode for SIBs, including exceptional rate capability with a specific discharge capacity of 403 mA h g–1 at a high current density of 3200 mA g–1. These findings could open up the efficient designing of smart hybrid electrodes using green techniques for next-generation energy storage systems.
Post O2 Plasma-Induced Fabrication of 1T-WS2/a-WO3 Heterostructure for Superior Hydrogen Evolution Reaction Electrocatalysts Via Hydrogen Spillover
Authors: Cho Jinill , Seok Hyunho , Kim Taesung
Published: February 2024

2D transition metal dichalcogenide (TMDC) group has been widely spotlighted as hydrogen evolution reaction (HER) electrocatalysts to replace the conventional Pt electrocatalyst due to their distinctive features of robustness, low cost, and accessibility to structural modification. However, the electrochemical activity of TMDC materials is mostly originated from its exposed edge sites, whereas its basal plane is relatively inert. There have been attempts to increase the relative fraction of active edge sites in the basal plane or employ the phase transition from semiconductive 2H phase to metallic 1T phase. The practical uses have been restricted compared to nobel metal Pt.

Plasma engineering is a facile method to functionalize their basal plane and generate vacancies into the lattice as active sites to improve electrocatalytic activity. In our previous works, MoS2 and WS2 has been synthesized to have abundant defects with maximized active edge sites to impart superior HER performance by employing Ar+H2S plasma treatment on tungsten (W) thin metal film with a thickness of 1 nm. However, to surpass the intrinsic electrochemical properites, we introduce 1T-WS2/a-WO3 (WSO) heterostructure via post O2 plasma treatment by exploiting a plasma enhanced-chemical vapor deposition (PE-CVD). There has been a limitation in obtaining the best electrocatalytic performances from the plasma assisted 1T-WS2 films because of its much lower hydrogen affinity of 1T-WS2. On the contrary, tungsten trioxide (WO3) shows strong hydrophilic property in that W atomic site of WO3 can easily absorb H2O. In this regard, 1T-WS2 with hydrophilic amorphous WO3 (a-WO3) can have the outstanding HER activity by inducing hydrogen spillover effect that is a hydrogen transport phenomenon from a-WO3 to 1T-WS2. a-WO3, which has relatively stronger hydrogen affinity, plays an important role in transferring the absorbed hydrogen to 1T-WS2 as active sites. As a result, the HER performance of WSO thin film can be optimized by means of controlling the amount of a-WO3 depending on the post O2 plasma treatment time. It was also confirmed from density functional theory (DFT) calculation that the hydrogen movement on the WSO surface related to hydrogen absorption energy difference between 1T-WS2 and WO3.
Optical and Mechanical Properties of Si-Based Thin Films for Photonic Applications
Authors: Mascher Peter , Ahammou Brahim , Azmi Fahmida , Landesman Jean-Pierre , Levallois Christophe
Published: February 2024

In this talk, we will review recent advances in the fabrication and characterization of silicon-based thin film structures for photonic applications, including rare earth doped silicon oxynitrides and luminescent silicon carbonitrides.

For Si-based materials to be used in solid-state lighting (SSL) and silicon photonics schemes it is necessary to have precise control of the optical emission from these materials. This can be accomplished using rare earth dopants such as Ce, Tb, and Eu to obtain blue, green, and red emissions, respectively. After a brief review of the latest developments in the field, this talk will focus on Eu-doped films, which are attractive for silicon photonic applications due to their intense emission in the visible spectral region [1]. The films are fabricated by electron cyclotron resonance plasma enhanced chemical vapour deposition (ECR-PECVD) and doping is accomplished using a novel hybrid radio frequency (RF) magnetron sputtering source in the ECR-PECVD reactor chamber [2]. This approach contrasts with traditional doping methods which use metal-organic precursors to introduce rare-earth dopant species into the host matrix. We will discuss the relationship between the photoluminescence, elasticity, and hardness of Eu doped silicon oxynitride (SiON) thin films.

As the efficiency of photonic devices can be influenced by the mechanical properties of the deposited films, a good understanding of their mechanical properties is required for the integration of these films in photonic devices. SiNx thin films, for example, play an important role in strain engineering of active photonic devices, such as diode lasers fabricated on GaAs or InP substrates. We will discuss results of a collaboration between McMaster and the Université de Rennes in France, aimed at quantifying the effects of structured dielectric thin films on the generation of a mechanical strain field in the semiconductor through tuning the amount of mechanical stress present in the dielectric thin film, as a function of the details of the deposition process [3].

[1] Fahmida Azmi et al., “Tunable Emission from Eu:SiOxNy Thin Films Prepared by Integrated Magnetron Sputtering and Plasma Enhanced Chemical Vapor Deposition”, J. Vac. Sci. Technol. A 40, 043402 (2022); https://doi.org/10.1116/6.0001761

[2] J.W. Miller et al., “Integrated ECR-PECVD and Magnetron Sputtering System for Rare-Earth-Doped Si-Based Materials”, Surface and Coatings Technology 336, 99 (2018); doi: 10.1016/j.surfcoat.2017.08.051

[3] Brahim Ahammou et al., “Strain engineering in III-V photonic components through structuration of SiNx films”, J. Vac. Sci. Technol. B 40, 012202 (2022); doi: 10.1116/6.0001352
A Comparison of Low-Temperature Deposition for SiO2 in PECVD Using SiH4 and TEOS
Authors: Kusuda Yutaka , Miyashita Takahiro , Asai Yuki , Nishinaka Hiroyuki
Published: February 2024

We have developed a method for depositing SiO2 as an insulating layer at temperatures below 100°C using PECVD. This method has potential applications in the development of flexible displays and organic transistors. We have previously reported on TSV via-hole formation by the Bosch process and TEOS-SiO2 deposition on sidewall by PECVD at 150°C [1]. In this study, we performed PECVD using a power supply frequency of 400 kHz. The deposition temperature was set at 100°C. We compared the deposition rates and the film stress of SiO2 films deposited using SiH4 and TEOS at different RF power densities.

Figure 1 shows the relationship between 400 kHz power and the deposition rates. In this power density range, the deposition rate of SiH4 was almost constant at approximately 52 nm/min regardless of power density. On the other hand, the rate using TEOS tended to decrease as the power density increased above 0.28 W/cm2.

Figure 2 shows the film stress of each film immediately after deposition and after few days of atmospheric exposure. The minus side of the stress indicates compressive stress. The stress of SiH4 was -50 to -70 MPa immediately after deposition; however, after few days of atmospheric exposure, the stress shifted by approximately -50 MPa at all power densities. On the other hand, in the case of TEOS, the stress did not change at approximately -120 MPa at a power density of 0.18 W/cm2 or higher immediately after deposition; however, after few days of exposure, the amount of change to the compressive stress side became smaller as the power density increased. It has been reported that the change in stress to the compressive side is influenced by moisture in the atmosphere [2]. The small change in stress is considered to mean that the film is denser, and that moisture is less likely to enter the film. The deposition rate is considered to decrease during the process of film densification.

In summary, it is thought that by increasing the power density with TEOS-SiO2, a dense film is formed even at a low temperature of 100°C.

References

[1]Y. Kusuda, T. Nonaka and S. Motoyama, Through Silicon Via (TSV) Using DRIE and Cathode Coupled PECVD, ECS Transactions, Volume 50 Number 32 p.3, (2013).

[2]I. Blech and U. Cohen, Effects of humidity on stress in thin silicon dioxide films, Journal of Applied Physics, 53, 6, (1982).

Figure 1
Investigating the Effect of Plasma Parameters on the Dielectric Constant of Sicoh Thin Films Grown by PECVD Using Dimethyldimethoxysilane
Authors: Choi Jinseok , Chae Gwang-Seok , Yeom H.J. , Kee Wonchul , Lee Hyo-Chang , Jeong Hyun-Dam , Kim Jung-Hyung
Published: February 2024

The demand for high-performance, low-power, and high-density semiconductor devices has led to the reduction in size of semiconductor chips, resulting in resistance-capacitance (RC) delay. To mitigate the RC delay, low dielectric constant (low-k) insulators have been developed, with the focus on developing new materials with lower dielectric constant. In this report, we present our investigation into the effect of electron density and temperature on the reduction of dielectric constant in SiCOH thin films, utilizing dimethyldimethoxysilane (DMDMS) as a variable with respect to pressure. Our results reveal that both electron density and temperature decline with increasing pressure due to localized electron kinetics and increased inelastic collisions between electrons and neutral species in the chamber, respectively. Our findings also show that the dielectric constant and refractive index of SiCOH thin films decrease at low electron density and temperature. Quadrupole mass spectroscopy reveals that CH3 radicals dissociate less at higher pressures, while Fourier transform infrared spectroscopy confirms an increase in Si-CH3 bonds in SiCOH thin films with increasing pressure. Our findings provide insights into the relationship between electron density and temperature and the dielectric constant of SiCOH thin films, which can contribute to the development of low-k insulators for high-performance semiconductor devices for applications such as big data, mobility, and the Internet of Things (IoT).
Utilizing Direct Membrane Deposition to Improve the Performance of Forward-Bias Bipolar Membrane CO2 Electrolysers
Authors: Alkayyali Tartela , Shayesteh Ali , Mar Harrison , Arabyarmohammadi Fatemeh , Miao Rui Kai , O'Brien Colin P. , Sargent Edward H. , Zhao Nana , Sinton David
Published: February 2024

The electrochemical conversion of CO2 to multi-carbon products (C2+), such as ethylene and ethanol, is an attractive technology towards achieving net zero carbon emission goals. Among the available configurations of CO2 electrolysers, those employing a bipolar membrane (BPM) in forward-bias mode (f-BPM) reduce CO2 loss to the anode – a problem commonly faced in traditional anion exchange membrane (AEM) electrolysers. Therefore, carbon efficiency (the percent of input CO2 that is converted to C2+ products) and system operational costs can be improved.

In f-BPM electrolysers, (bi)carbonate ions move through the AEM then combine with protons moving through the cation exchange membrane (CEM) to regenerate CO2 and H2O at the AEM|CEM interface. Recent reports have implemented a porous AEM structure or an added AEM|CEM interface channel to aid the movement of CO2 from the AEM|CEM interface to the cathode and, thus, avoid blistering. Despite the advantage of f-BPM CO2 electrolysers, their performance is limited by the parasitic H2 evolution reaction (>20% Faradaic efficiency, or FE) and the low C2+ FE (<40%) at industrially relevant reaction rates (≥200 mA cm-2). We attribute this performance limitation to the unintended gaps between the used AEM and CEM. Inadequate contact between the AEM and CEM is anticipated to reduce the extent of local CO2 regeneration and promote unwanted proton crossover to the cathode; both phenomena could be contributing to the commonly observed FEs.

In this report, we enhanced the contact between the AEM and CEM through the use of direct membrane deposition (DMD) over a Cu-based cathode. The DMD approach enabled modular control over the AEM and CEM thicknesses and structures, which improved ion and gas transport. Through electrochemical impedance spectroscopy, the DMD system was observed to improve the mass transport by >58% compared to a system that is similar to current f-BPM electrolysers (i.e., control system). The facilitated mass transport resulted in a reduction of the operating cell potential (by 0.84 V) and an enhancement of the C2+ FE to 65% (from 29% in the control system) at 300 mA cm-2. The flexibility of the DMD approach also enabled the fabrication of asymmetric BPMs, resulting in a record low H2 FE of 12% at 300 mA cm-2. We also demonstrated a 79% single-pass CO2 conversion (SPC) with 67% C2+ FE, resembling the highest simultaneous SPC and C2+ FE achievement at high current density (300 mA cm-2)among current f-BPM electrolysers. The DMD benefit was also applicable to other types of CO2 electrolysers, such as CO2-to-CO silver catalyst electrolysers, in which the CO FE was boosted to 90% (from 65% in the control system) at 90 mA cm-2.

Figure 1