bluuebunny/crossref_metadata_2025_split huggingface dataset:
(Digital Presentation) Development of a Low-Torque Transfer System Using a Progressive Cavity Pumps with Gels
Authors: Sato Daisuke , Watanabe Yosuke , Ogawa Jun , Shiblee Nahin Islam , Khosla Ajit , Kawakami Masaru , Furukawa Hidemitsu 
Published: July 2022

Progressive cavity pumps (PCPs) consist of a rotor and a stator. The extrusion process of PCPs is governed by a single-helical rotor which rotates eccentrically within a double-helical stator of twice the pitch length. Between the seal lines (the contact lines of rotor and stator), there are cavities which are constantly moved towards the discharge end of the pump. As one cavity is eliminated, another cavity develops, keeping the cross-sectional area of the cavities constant. The process makes a continuous non-pulsating flow in the PCPs. The developed pushing–and–suction action allows PCPs to exert significantly lower shear rates on the pumped material, compared to other pump types, such as membrane pumps or peristaltic pumps. However, the sliding of the rotor and stator in the pump causes a biting phenomenon [1-3]. Therefore, the degradation of particles in the fluid occurs. In this study, we adopted a flexible, low-friction gels as the stator material. By using gels materials as stator, we could make a pump that could discharge at low torque as previously reported by our group [4]. In this work, the rubber stator and the gels stator fabricated by 3D printing were compared and evaluated by performing discharge and torque test.
References:
[1] K. Nishimura, E. Uetsuji, and Y. Iwai, “Study on the Behavior of Particles in the Sliding Portion of a Progressive Cavity Pump”, Journal of Japanese Society of Tribologists, Vol. 63 (2018), No. 9 pp. 641-650
[2] P. Fisch, M. Holub, and M. Z. Wong, “Improved accuracy and precision of bioprinting through progressive cavity pump-controlled extrusion”, 2021 Biofabrication 13 015012
[3] M. Horie, S. Shigemitsu, S. Ookura, “Fundamental Study on Pediatric Single Eccentric Screw Blood Pump”, Turbomachinery, vol. 43(2015), No.4 pp.222-228
[4] Yeh, Yee Cheng, Naoya Yamada, Yosuke Watanabe, MD Nahin Islam Shiblee, Jun Ogawa, Ajit Khosla, Masaru Kawakami, Teruaki Akamatsu, and Hidemitsu Furukawa. “3D Printing of Soft-Matter Mono Pump in Infant Ventricular Assist Device (VAD) for Blood Pumping” ECS Transactions 98, no. 13 (2020): 31.
Tunable Polarity in WSe2/TiS2 Van Der Waals Heterostructure
Authors: Lee Tae-Ju , Song Tae-Seop , Seong Tae-Yeon 
Published: July 2022

Two-dimensional (2D) transition metal dichalcogenides (TMDs) formed layered van der Waals (vdW) crystals have emerged as promising candidates for varieties of potential applications, such as gas sensors, photodetectors, light-emitting diodes, Schottky diodes and memories, due to their unique physical features. However, since the existence of the metal-induced gap states (MIGS) at metal-semiconductor interfaces, it is severely difficult to adjust their electrical properties. It was demonstrated in previous researches that various metal contacts on TMDs semiconductor exhibit regular Schottky barrier height by Fermi-level pinning effect.
In this study, we suggest the van der Waals material contact between TiS2 semimetal and WSe2 semiconductor for leading van der Waals gap at their interface. Through this approach, the TiS2/WSe2 2D heterojunction can efficiently address the MIGS. Interestingly, the TiS2/WSe2 heterojunction exhibits a novel electrical transport characteristics such as distinct ambipolar and rectifying behaviors by tuning drain voltage polarity. Firstly, under reverse bias (V
ds < 0), TiS2/WSe2 heterojunction operates efficiently and allows transport of the carriers at both polarities of the gate voltage (V
bg < 0 and V
bg > 0), namely ambipolar behavior. Secondly, under the forward bias (V
ds > 0), TiS2/WSe2 heterojunction does not allow transport of the electrons at positive gate voltage (V
bg > 0), but allow transport of the holes at negative gate voltage (V
bg < 0), namely p-type behavior. To understand the carrier transport mechanism of these results, ultra-violet photoelectron spectroscopy (UPS) measurements were also carried out on the WSe2 and TiS2 flakes. It is noted that the TiS2/WSe2 junction plays a crucial role in determining a novel electronic property of this device.

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(Digital Presentation) Thermal Runaway Initiation, Propagation and the Potential for Propagation Inhibition in Commercial Automotive Lithium-Ion Cells and Modules
Authors: Podias Andreas , Kriston Akos , Pfrang Andreas 
Published: July 2022

Lithium-ion batteries, containing flammable electrolytes, have become safer in many ways since their invention. As the technology matures, energy and power densities increase: the European Council for Automotive R&D set 2030 (cell level) targets for battery electric vehicle energy density of 1000 Wh L-1, with 450 Wh kg-1 specific energy and 1800 W kg-1 peak specific power. This rise in energy and power densities increases the risk of accidental release of energy from the batteries and thermal runaway (TR). Safety is thus a key concern when designing a lithium-ion battery system for electric vehicles (EV).
TR relates to fast heating of a battery cell caused by exothermic chemical decomposition reactions of the materials inside the cells. It develops in a cell when heat is generated and cannot be dissipated quickly enough to the surroundings, giving rise to an abrupt (exponential) temperature increase and subsequent reaction rate increase. During TR, various exothermic side reactions can occur, leading to temperature increase, accompanied by pressure increase as electrolyte evaporates and venting. This can result in the emission of highly flammable gas and the formation of toxic atmosphere, as well as, in fire and, in very rare circumstances, in explosion. The corresponding temperature increase in adjacent cells (or modules) might then be sufficient to cause them to also go into TR – leading to a process known as thermal runaway propagation (TRP).
Fit-for purpose testing procedures to assess the risks associated with TRP are therefore of utmost importance and the focus should always be the safety of the EV occupants, bystanders, first responders and property. Some tests in current standards and regulations try to simulate internally driven failures (e.g. internal short circuit), but whether these tests are suitable to represent field failures remains an open question.
This work will give an insight into two selected TR initiation methods assessed within JRC’s TR initiation and propagation test campaigns, namely (a) localised rapid external heating, as developed and patented internationally by NRC (National Research Council Canada) and (b) ceramic nail penetration, as described in the IEC TR 62660-4 standard. It examines the response of short-stacks of pouch cells extracted from automotive batteries after TR is triggered in a single cell. Experimental data and analysis to better understand how TR propagates and the potential for TRP inhibition will be reported. The potential of inhibiting TRP is explored on 2- and 5-cell assemblies with a multi-layer, porous, composite insulation material between cells. Separating the cells can delay significantly TRP in adjacent cells in modules constructed with pouch cells, whereas TRP may be slowed and even inhibited as the thickness of the multilayer material varies.
(Digital Presentation) High-Resolution Imaging of Active Sites Under Reaction Conditions for Carbon-Based Electrocatalysis
Authors: Haid Richard W. , Kluge Regina M. , Schmidt Thorsten O. , Calle-Vallejo Federico , Bandarenka Aliaksandr S. 
Published: July 2022

Due to the abundance and the electrochemical versatility of carbon, it is becoming an increasingly popular material for electrocatalytic applications. Whether it is used as a support material, as a catalyst, or even as a bifunctional catalyst, insights into the reaction processes are of fundamental value. In this light, we employ electrochemical scanning tunneling microscopy (EC-STM) to in-situ evaluate electrode surfaces' behavior and identify the nature of the active sites.[1] The experimental distinction between inactive and active sites of a catalytic system can be achieved by comparing the noise level of surface sites in the EC-STM signal while a reaction is ‘Off’ or ‘On’, respectively. The tunneling current will be stable under both conditions if the scanning tip is positioned over an inactive site. Over an active site, reactions occurring within the tunneling gap will influence the EC-STM signal, which can be observed as locally confined noise features superimposed on the surface morphology.
Here, we examine highly ordered pyrolytic graphite (HOPG) in alkaline and acidic media as a model system for carbon-based structures. In an alkaline medium, we compare the activity of specific surface sites under oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) conditions (Figure 1a).[2] In both cases, predominantly steps and defects are active. However, in the case of the OER, the terraces also play a role. For the hydrogen evolution reaction (HER) in acidic media, it was possible to identify individual active sites on the ‘honeycomb’ structured surface with down to atomic resolution (Figure 1b).[3] Apart from HOPG, the technique will be demonstrated for metal-organic frameworks, another class of promising catalysts for ORR and OER.
References:
[1] Pfisterer, J. H.; Liang, Y.; Schneider, O.; Bandarenka, A. S. Nature
2017, 549, 74.
[2] Haid, R. W.; Kluge, R. M.; Schmidt, T. O.; Bandarenka, A. S. Electrochim. Acta
2021, 382, 138285.
[3] Kluge, R. M.; Haid, R. W.; Stephens, I. E. L.; Calle-Vallejo, F.; Bandarenka, A. S. Phys. Chem.

Figure Caption:

Figure 1: a) n-EC-STM measurement of a step under ORR (red) and OER (green) conditions, as well as during reaction ‘Off’ (blue). The most active sites in both cases can be found at steps, indicated by the distinct noise spikes at these positions compared to reaction ‘Off’. Terraces are inactive towards the ORR. However, they do play a role in the OER.[2] © 2021 Elsevier Ltd. b) Atomically resolved active sites on HOPG under HER conditions. Bright spots in the measurements indicate active centers. They can be observed predominantly at step edges and defects, while the basal plane (terrace) remains inactive.[3]
© 2021 The Royal Society of Chemistry

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Metal Selenide Anchored Carbon Nanotube for Boosted Oxygen Evolution Reaction
Authors: Singh Harish , Nath Manashi , Liyanage Wipula Priya Rasika 
Published: July 2022

The oxygen evolution represents an important reaction in electrochemical water splitting and metal-air batteries. To deal with the increasing energy crisis and demand for sustainable clean energy, production of low-cost, high-efficiency, and robust oxygen evolution reaction (OER) electrocatalysts is urgently needed. Recently, transition metal chalcogenides (TMCs) have been used as active electrocatalysts for OER because of their high electrical conductivity and enhanced electrochemical activity. These chalcogenides based electrocatalysts show unprecedented high efficiency for OER exhibiting very low overpotentials, thereby surpassing state-of-the-art precious metal oxides or hydroxide-based catalysts. Carbon nanostructures have been shown to significantly improve their electrocatalytic performance even further. In the present work, nickel selenide nanorods (NRs) were grown inside carbon nanotubes (NiSe@CNT) through chemical vapor deposition (CVD) wherein, the carbon nanotube formed in-situ wrapping around the growing nickel selenide nanorods. Such intimate intermixing is expected to aid in rapid electron transfer from the catalyst composite and yield significantly higher current density. The encapsulation with a CNT shell can also expectedly increase stability of the selenide phase with respect to corrosion and anion leaching. Electrocatalytic behavior was explored by various electrochemical studies, including linear sweep voltammetry (LSV), chronoamperometric experiments, electrochemical surface area determination, and Tafel slope determination, under highly alkaline condition. It was observed that this NiSe@CNT composites showed enhanced electrocatalytic activity for OER. Our results indicate that the self-grown CNT around nickel selenide increases catalytic activity of this hybrid nanostructure due to an increased number of catalytic sites and electronic conductivity of the nanocomposite. The overpotential at 10 mA cm-2 for the as-synthesized NiSe@CNT catalyst is 270 mV which is much better than precious metal based electrocatalysts for OER, such as RuO2 and IrO2. In addition, the current-voltage plots were superimposable before and after 40 h of chronoamperometry test, confirming that the as-synthesized catalyst gives stable electrocatalytic OER activity in 1 M KOH medium for an extended time period. The as-synthesized catalyst was characterized by XRD, Raman spectroscopy, XPS and TEM for morphology, elemental and chemical compositions.
Keywords: oxygen evolution reaction, carbon nanotubes, In-situ wrapping

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(Digital Presentation) Strategy to Enhance the Power Factor in Carbon Nanotubes
Authors: Yanagi Kazuhiro 
Published: July 2022

Flexible thermoelectrics, which can convert waste heat into electricity at surfaces with various shapes and moving parts, is one of important techniques for efficient use of our limited energy resources. Carbon nanotubes are one of possible candidates for flexible thermoelectrics, and then we have investigated the relationships between electronic structure, location of Fermi-energy level, morphology, and thermoelectric performance of the carbon nanotubes. Particularly, we have clarified the one-dimensional characteristics in thermoelectric properties of single walled carbon nanotubes (SWCNTs). In the case of metallic SWCNTs, the thermoelectric trade-off is violated when the Fermi-energy level is tuned around van hove-singularity [1]. Thus, simultaneous enhancement of Seebeck coefficient and electrical conductivity is possible in the metallic type. In the case of semiconducting SWCNTs, we theoretically clarified that it is very difficult to identify the 1D characters in the properties of their Seebeck coefficient, power factor, and electrical conductivity. We found it is necessary to clarify the relationships between thermoelectrical conductivity (L12 term) and electrical conductivity (σ) to discuss the dimensionality in thermoelectric properties of semiconducting nanomaterials. We observed clear peak structure in the L12-σ plot in high-purity (6,5) SWCNT thin films, reflecting the 1D traces in semiconducting SWCNTs[2]. Morphology control is also important to enhance power factor of carbon nanotubes. The Seebeck coefficient does not depend on the directions of heat flow and nanotube axis, but the electrical conductivity can be enhanced when the current direction is parallel to the nanotube axis [1, 3]. On the basis of above characteristics, we determined the following strategy to enhance the power factor (PF) of SWCNTs.

Fine tuning of Fermi-energy level in the metallic type of nanotube can enhance PF

Aligned nanotubes with good electrical conductivity can enhance PF.

Thus, we started to study the thermoelectric properties of carbon nanotube fibers with extremely good electrical conductivity, which are produced by Prof. Pasquali Group in Rice Univ [4]. As a result, we found the gigantic power factor of the nanotube fiber, which is 14 mWm-1K-2, with proper Fermi-level tuning [5]. Flexible thermoelectrics with such large PF will be useful for active cooling application.
References:
[1] Ichinose et al., Nano Lett. 19, 7370 (2019) [2] Ichinose et al., Phys. Rev. Mater. 5, 025404 (2021) [3] Fukuhara et al., Appl. Phys. Lett. 113, 243105 (2018) [4] Behabtu et al., Science 339, 182 (2013) [5] Komatsu et al. , Nature Comm. 12, 4931 (2021)

Figure 1
Highly Exfoliated N-Doped Reduced Graphene Oxide Derivatives Synthesis and Application
Authors: Genorio Bostjan , Nosan Miha 
Published: July 2022

Carbon-based nanomaterials such as graphene, graphene oxide, carbon nanotubes, graphene nanoribbons, etc. are considered as promising materials for energy storage and conversion, electrode sensing, optical and electronic applications. High specific surface area, porosity, and chemical modifications are some of the most important factors for tailoring the (electro)chemical, physical, and mechanical properties of graphene derivatives.1 Nitrogen-doped graphene derivatives have been identified as promising materials for energy storage and conversion2 and sensing applications. One of the most common syntheses of N-doped graphene derivatives is the N-doping of graphene oxide prepared by the Hummers method. The methods for simultaneous N-doping and reduction of graphene oxide are diverse: thermal annealing, pyrolysis, solvothermal, laser ablation, microwave-assisted, and hydrazine treatment.1 However, the above methods yield N-doped graphene derivatives, which are usually poorly exfoliated and have a low specific surface area. Therefore, an efficient strategy to improve the specific surface area of N-doped graphene oxide derivatives needs to be developed.3

Herein we present a new "induction heating method" for the preparation of N-doped reduced graphene oxide derivatives (N-rGOD) with a high specific surface area. N-rGOD was prepared in a two-step process from commercially available graphites (Gs) and multi-walled carbon nanotubes (MWCNTs). In the first step, graphite oxide precursors were synthesized from Gs or MWCNTs by the improved Hummers method. In the second step, the graphite oxide precursors were subjected to rapid heat treatment by induction heating in a reductive ammonia atmosphere. Due to the rapid thermal expansion of graphite oxide, massive exfoliation occurred to obtain N-rGOD with higher specific surface area.4 These materials were tested for energy storage and conversion applications and showed excellent properties.

References

(1) Xu, H.; Ma, L.; Jin, Z. Nitrogen-Doped Graphene: Synthesis, Characterizations and Energy Applications. J. Energy Chem.
2018, 27 (1), 146–160. https://doi.org/10.1016/j.jechem.2017.12.006.
(2) Nosan, M.; Löffler, M.; Jerman, I.; Kolar, M.; Katsounaros, I.; Genorio, B. Understanding the Oxygen Reduction Reaction Activity of Quasi-1D and 2D N-Doped Heat-Treated Graphene Oxide Catalysts with Inherent Metal Impurities. ACS Appl. Energy Mater.
2021. https://doi.org/10.1021/acsaem.1c00026.
(3) Alazmi, A.; El Tall, O.; Rasul, S.; Hedhili, M. N.; Patole, S. P.; Costa, P. M. F. J. A Process to Enhance the Specific Surface Area and Capacitance of Hydrothermally Reduced Graphene Oxide. Nanoscale
2016, 8 (41), 17782–17787. https://doi.org/10.1039/c6nr04426c.
(4) Qiu, Y.; Guo, F.; Hurt, R.; Külaots, I. Explosive Thermal Reduction of Graphene Oxide-Based Materials: Mechanism and Safety Implications. Carbon N. Y.
2014, 72, 215–223. https://doi.org/10.1016/j.carbon.2014.02.005.
Hybridization of Mesoporous Carbon and Iron Oxide for Better Mitigation of Polysulfide Shuttling in Li-S Batteries
Authors: An Meichun , Aziz Mohammad Abdul , Joo Yong Lak 
Published: July 2022

With a higher theoretical capacity, lithium-sulfur (Li-S) batteries have been considered as promising candidates for next-generation batteries. Due to the non-conducting nature of sulfur, however, lithium-sulfur batteries tend to exhibit poor performance at a high current rate (C-rate).
Here we demonstrate that Fe3O4, synthesized from precursor iron (III) acetylacetonate (AAI), and mesoporous carbon material, Ketjen Black (KB), can be synergistically combined to enhance the electrochemical performance of lithium-sulfur batteries substantially. Instead of adding commercial magnetite particles into Li-S cathodes, iron oxides are synthesized and imbedded into KB from a precursor, AAI, through thermal treatments in air and Ar. The sulfur, then, is incorporated into iron oxides/KB hybrids by melting at an elevated temperature. With air-controlled electrospray as the processing method, sulfur embedded iron oxides/KB, poly(acrylic acid), and rGO sheets are mixed and directly deposited onto the carbon-coated aluminum collector, to employ as the Li-S battery cathode. X-ray diffraction (XRD), scanning electron microscopy (SEM), and electrochemical impedance spectroscopy (EIS) studies confirm that Fe3O4 and iron carbide (Fe3C) are synthesized from the precursor, AAI, embedded in mesoporous carbon materials, and reducing the charge transfer resistance of batteries. The rate-capability tests show that systems with KB/Fe3O4 can achieve enhanced performance compared to batteries without iron oxides, especially at high C-rates. With 14 wt % of solid materials as iron oxides and iron carbide, batteries exhibit 750 mAh/g at 2C discharge/charge rates, which is 83% higher compared to systems without iron oxides. However, incorporated via 250 °C for 0.5 hr in air and 850 °C for 2 hr in Ar, the composite of KB/Fe3O4/Fe3C induces irreversible side reactions during the initial charging process, which causes a huge difference in capacity between the first and the second cycle. To achieve an optimal status with improved rate capability and acceptable initial charging time, we modify the thermal treatments and thus increase the proportion of Fe3O4 in the mixture. According to the postmortem analysis, cathodes with iron oxides can interact with soluble polysulfides strongly and alleviate the polysulfide shuttle effect significantly, compared with those without Fe3O4. Such enhanced rate capability by KB/Fe3O4 (synthesized) over KB only or KB/Fe3O4 (commercial) systems suggests that the incorporation of iron oxides can play an important role in improving the electrical conductivity of cathode and mitigating polysulfide shuttle effect.

Figure 1
Effect of Temperature on the Graphitizability and Electrochemical Properties of a Quang Ninh Natural Anthracite Used As Anode in Li/Na-Ion Batteries
Authors: Le Phung , Le Kha Minh , Doan Thuy Vo Bien , Nguyen Hoang Van , Tran Man V. 
Published: July 2022

Abstract

In this research, natural anthracite coal (ATC) originated from Vang Danh - Quang Ninh province in Viet Nam was firstly chemically purified and then calcined in inert gas (Ar) at 800 oC for different periods (t = 2, 3 and 6 h) to remove all the impurities and enrich the carbon content. The purity and graphitized structure of treated coal proved significantly while evaluating its structural parameters (the lateral crystallite size - La, stacking crystallite height - Lc, the average number of layers per carbon crystallite - Naverage, and the average number of carbon atoms per aromatic lamellae - n)1, 2 and morphology. After purification step, ATC possesses relatively high carbon content (96.0%) and its impurities were mostly removed. The structure of heat-treated ATC samples is like hard carbon. Besides, its graphene interlayer spacing is larger than that of graphite. These features seem to be potential for application of ATC as negative electrode materials for both Li and Na rechargeable batteries.
In batteries testing, using ATC calcined at 800 oC for 3 hours as anode material in lithium half-cell exhibited a quite good specific capacity (170.1 mAh g-1), which is much higher than the value obtained for commercial hard carbon (162.2 mAh g-1). Moreover, Coulombic efficiency of ATC is almost absolute (99.8%). In sodium half-cell, the sample calcined at 800 oC for 2 hours gave much smaller specific capacity of 130.5 mAh g-1 than hard carbon one (280 mAh g-1). Nevertheless, Coulombic efficiency of ATC anode in lithium half-cell and sodium half-cell throughout 100 cycles remained absolutely at 99.6%, while their values for hard carbon anode were 99.9% and 99.7%, respectively.

References

Abou-Rjeily, J.; Laziz, N. A.; Autret-Lambert, C.; Outzourhit, A.; Sougrati, M.-T.; Ghamouss, F., Towards valorizing natural coals in sodium-ion batteries: impact of coal rank on energy storage. Scientific Reports
2020,
10 (1), 1-10.

Manoj, B.; Kunjomana, A., Study of stacking structure of amorphous carbon by X-ray diffraction technique. Int. J. Electrochem. Sci
2012,
7 (4), 3127-34.

Acknowledgement

This work is supported by Viet Nam National University Ho Chi Minh City (VNUHCM) under grant number B2020-18-06