bluuebunny/crossref_metadata_2025_split huggingface dataset:
First Principles Investigation of Grain Boundary Effects in Perovskite-Type Lithium Lanthanum Titanate Solid Electrolyte
Authors: Conlin Patrick Richard , Cho Kyeongjae 
Published: February 2020

Lithium lanthanum titanate (LLTO) is considered a particularly promising candidate for use as an electrolyte in all-solid-state lithium ion batteries due its good electrochemical stability and high ionic conductivity. However, measured values for the ionic conductivity of LLTO fall far below theoretical predictions, an incongruity which has been attributed to the presence of grain boundaries. Furthermore, recent experimental work has shown that lithium dendrite growth occurs along the grain boundaries in LLTO. While experimental studies have been able to reveal the detailed microstructure of polycrystalline LLTO, but little effort has been made to identify the fundamental mechanisms at work within the grain boundaries which lead to to suppressed ionic conductivity and Li dendrite growth. Using ab-initio calculations, we examine the electronic character of LLTO grain boundaries and investigate the impact of the defect states on ion transport and dendrite formation. Based on a fundamental understanding of the atomic and electronic character of LLTO grain boundaries, material design approaches are proposed to mitigate the impact of grain boundary behavior and improve the viability of LLTO as a practical solid electrolyte.
This work was supported by the International Energy Joint R&D Program (No. 20168510011350) of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) grant funded by the Ministry of Knowledge Economy, Korean government. This work is also supported by the L&F Co.’s World Class 300 Project of the Korea Institute of Advancement of Technology (KIAT) funded by the Ministry of Trade, industry and Energy (No.S2483103).
Failure Analysis of the Rechargeable Porous Zinc Electrode in Alkaline Electrolyte
Authors: D'Ambrose Michael Joseph , Yadav Gautam Ganapati , Turney Damon , Gallaway Joshua W. , Nyce Michael , Messinger Robert J. , Banerjee Sanjoy 
Published: February 2020

Metallic zinc (Zn) is an attractive negative electrode material for rechargeable batteries because it is a non-toxic, earth abundant metal. It has a low equilibrium potential of -1.35 V vs. mercury-mercuric oxide (Hg|HgO) in concentrated alkaline electrolyte, a high gravimetric discharge capacity of 820 mAh/g, and a high volumetric discharge capacity of 5850 mAh/mL. During discharge, Zn oxidizes and forms a dissolved complex known as the zincate ion, Zn(OH)4
2-, from which zinc oxide (ZnO) precipitates as a solid. On charge, Zn(OH)4
2- is reduced to metallic Zn. Motivation to study the Zn electrode in rechargeable batteries is driven by a target overall battery energy density of 200 Wh/L that is sustainable for 500 or more charge-discharge cycles. This corresponds to a Zn electrode volumetric capacity of 650 mAh/mL.
The cycle life of the porous Zn electrode in concentrated alkaline electrolyte is observed to decrease with increasing percentage of discharge capacity of Zn accessed. The percentage of discharge capacity of Zn accessed is known as the depth of discharge (DOD). Zn electrodes were cycled in the range of 1% to 15% Zn DOD in zinc-manganese dioxide (Zn-MnO2) batteries and in the range of 15% to 30% Zn DOD for zinc-nickel (Zn-Ni) batteries. Additives were incorporated into the zinc electrodes for the tests done on Zn-Ni batteries. Additives used were surfactant cetyltrimethylammonium bromide (CTAB), bismuth oxide (Bi2O3), synthetic layered silicate Laponite, and calcium hydroxide (Ca(OH)2). The potential values of the Zn electrodes vs. Hg|HgO reference electrodes were recorded.
During healthy galvanostatic discharge, Zn electrodes displayed a nearly constant potential vs. Hg|HgO at approximately -1.35 V. Tests that failed due to Zn exhibited a shift from this equilibrium potential that corresponded to a loss of cell voltage. This shift may be attributed to a concentration overpotential as ZnO is precipitated, thereby inhibiting the hydroxide ions from reaching the reacting metal interface. The shift may also be due to formation of a passivated layer on the electrode which effectively blocks the remaining active material. There are multiple regimes observed in the potential curves of the Zn electrode vs. Hg|HgO prior to cell failure. Beyond the healthy plateau at -1.35 V, a sloping potential is observed. This is followed by an additional plateau. The second plateau shifts with increasing cycle number and precedes cell death. See the attached figure for discharge curves of a Zn electrode cycled at 11.3% Zn DOD. After the second plateau a steep slope is observed in the potential for later cycles, which is believed to be due to passivation of the Zn electrode. The additives were observed to modify the discharge potential curve of the Zn electrode vs. Hg|HgO.

Figure 1
(Invited) Photo-Electrode Hybrid Materials Based on Metal-Oxide and Pi-Conjugated Units for Solar-Energy Conversion Devices
Authors: Santoni Marie-Pierre , Jouini Mohamed , Delices Annette , Xu Zijun , Dong Chang-Zhi , Bellynck Sebastien , Rutkowska Iwona Agnieszka , Kulesza Pawel J. 
Published: February 2020

Multi-component inorganic-organic hybrids are tunable units used to build-up mesoscopic architectures / devices for various applications. We focus our interest on hybrid materials for the elaboration of photoelectrodes to be integrated into solar-energy conversion devices, such as solid-state Dye-sensitized Solar Cells (ss-DSCs, for photovoltaic conversion) and Dye-sensitized PhotoElectrosynthesis Cells (DSPECs, for photocatalytic conversion to “Solar Fuels”).
In order to improve charge transfers and transport within photoelectrodes, along with overall stability and efficiency, we use controlled-deposition electrochemical techniques (for example, in situ electro-assisted PhotoElectroPolymerization (PEP)) for the preparation of the Hole-Transporting Material (HTM, used as a charge carrier within the device) on the photosensitized mesoporous semi-conductor of the electrode. This allows a better filling of mesoporous materials and a better contact between the components of the hybrid material/electrode.[i] We also remove the physical interface between components (for example, between Dye/HTM) by introducing a covalent bond between components (molecular engineering of bifunctional conjugates).[ii]
We will present our recent progress on NiO-based p-type photocathodes for low-temperature CO2 reduction, based on electrocatalytic and photoelectrochemical approaches.
[i] Zhang, J. et al. Nano Energy,
2016, 19, 455-470.
[ii] A. Delices et al.
Electrochim. Acta,
2018, 269, 163-171.

Figure 1
(Invited) Multifunctional Surface-Enhanced Raman Spectroscopy (SERS) Probes for Targeted Detection of Cancer Cells
Authors: Li Ming 
Published: February 2020

Cancer continues to raise global concerns with a significant mortality rate and an equally substantial socio-economic burden. As is well-known, cancer begins with out-of-control cell growth. To effectively screen and treat cancer, it is essential to identify and distinguish various subtypes of cancer cells as well as normal cells in solid tissues or body fluids, which will significantly improve personalized individual medical treatment. This talk will present our recent studies for identification and discrimination of subtypes of cancerous cells using surface-enhanced Raman spectroscopy (SERS).
The philosophy in our work is to actively target the overexpressed biomarkers on the surface of cancer cells with our functionalized SERS probes. The urea-based small-molecule inhibitor is grafted onto the SERS probe to endow with specificity for prostate-specific membrane antigen (PSMA) overexpressed on the surface of bone metastasis-derived, androgen independent isogenic PC3-PIP cells. Our finding shows high-resolution targeted SERS imaging of PC3-PIP cells in contrast to its phenotypically identical PC3-Flu cells with negatively-expressed PSMA. The significantly amplified SERS signal in the SERS probe endows the extraordinary sensitivity. The developed SERS routine is able to identify PC3-PIP cells in body fluids and solid tissues, providing an effective avenue for assessment of prostate cancer burden and image-guided surgery/treatment. Following this, a ratiometric SERS strategy is developed to discriminate breast cancer cells—MDA-MB-231 and MCF-7 cells. Two different SERS probes with distinct SERS signals are functionalized with two peptides that are able to specifically target the urokinase plasminogen activation receptor (uPAR) and epidermal growth factor receptor (EGFR), respectively. Our results show that we can distinguish MDA-MB-231 cells from MCF-7 cells by the SERS intensity ratio. The present finding offers a compelling approach to discriminate subtypes of cancerous cells to assess the progression and stage of cancer. More importantly, the present SERS technique has potential for the rapid identification and discrimination of subtypes of multiple cancerous cells owing to the powerful multiplexing capability in SERS.
Microscale Surface Nanostructuration and Catalysis of Metallic Electrodes through Electrochemical Deposition and Dissolution in Ionic Liquids
Authors: Jiang Junhua , Mariani Robert 
Published: February 2020

Incorporation of highly active nanostructures into metallic electrode surface layers is of particular interest for a wide range of potential applications, such as electrochemical sensing and energy storage-conversion systems, because the nanostructures not only can increase the active area accessible to reactant molecules but can also improve electron mobility in the solid ligaments. However, controlling the nano-architecture of electrode surface layers faces great challenges since metals at nanoscale favor low surface areas in order to minimize the surface energy. In the past two decades, several strategies such as template synthesis, surfactant mediated synthesis and dealloying, have been developed to design and fabricate nanostructured electrodes with highly ordered networks and high surface area. We have developed a green-chemistry method based on in-situ electrochemical deposition-dissolution (ECDD) of an active metal on a target metal substrate in ionic liquids to achieve the nanostructuration of metallic electrodes.1-4 As shown in Figure 1A, during electrochemical deposition, a highly reactive metal component such as Zn is introduced via electrodeposition to interact with a less active electrode substrate such as Au to form an alloy phase. During subsequent electrochemical dissolution, the reactive component is selectively removed from the alloy phase leading to the formation of nanostructured surface layers. The nanostructured layers can grow deeper by repeating the process. The most obvious advantage of the ECDD method over other arts is that no net chemicals are consumed and it is a green-chemistry process. This method has been employed to successfully create different nanostructures on single-element metal and alloy electrodes at tens-to-hundreds micrometer scales, which are shown in Figure 1B to E.
In this presentation, we will introduce the green-chemistry method based on the electrochemical alloying-dealloying in ionic liquids, the characterization and polarization behavior of resulting surface nanostructures, further catalysis of the nanostructures, and their applications to electrochemical sensing and energy storage conversion.

References

[1] J. Jiang, N. Holm, K. O'Brien, ECS Journal of Solid State Science and Technology
4 (2015) S3024-S3029.
[2] J. Jiang, L. Zhang, Electroanalysis
29 (2017) 2019-2026.
[3] J. Jiang, L. Zhang, ECS Journal of Solid State Science and Technology
4 (2015) N5084-N5088.
[4] J. Jiang, L. Zhang, X. Wang, ACS Appl. Mater. Interfaces
5 (2013) 12689–12694.

Figure 1
Engineered Electroactive Solutions for Electrochemical Detection of Volatile Organic Biomarkers Associated with Disease
Authors: Willis Christina Nicole , Misra Mano , Mohanty Swomitra K. 
Published: February 2020

Rapid screening of tuberculosis (TB) by evaluation of associated volatile organic biomarkers (VOBs) in breath has been shown to be a promising technology that is significantly faster and more convenient than traditional sputum culture tests. Methyl nicotinate and methyl p-anisate have been isolated as specific biomarkers for the mycobacterium tuberculosis, as they are not found in high concentrations in ambient air or the breath of healthy patients, but should be readily present in all patients with active TB. A novel approach to detection of these biomarkers in liquid form (e.g. from breath condensate) using inexpensive screen-printed electrodes will be presented. Previous modelling studies [1] suggest that these biomarkers complex with certain transition metals (such as cobalt and copper) given a particular bias voltage and oxidation state of the metal. This interaction can be exploited by mixing the sample solution containing the biomarkers into an electroactive solution (EAS) containing the functional metal ion, and observing the change electrochemically. For example, the cyclic voltammogram of copper (II) changes significantly when as little as 1 mM methyl nicotinate (MN) is added to the solution. The variation of peak oxidation voltage with MN concentration can be seen in Figure 1 below. In order to further understand the reactions taking place and specifically identify the biomarkers, square wave voltammetry (SWV) is employed to show which oxidation states of the functionalized metal are complexing with the biomarker of interest. Figure 2 shows the SWV of a copper EAS with and without 1 mM MN. The SWV shows a peak for each redox transition of copper, and how the area of each is affected by the addition of the biomarker. In this way, a “fingerprint” method can be used to identify biomarkers once their known interaction is established.
[1] Ray R, Sarma B, Mohanty S, Prisbrey K, Misra M. Assessment of metals in detection of TB biomarkers: Novel computational approach. Journal of Materials Chemistry and Physics. 161 (2015) 1-8

Figure 1
(Invited) Multi-Material Additive Manufacturing (3D/4D printing)
Authors: Khosla Ajit , Basher Samiul , Thundat Thomas , Bhansali Shekhar , Nagahara Larry A. , Kawakami Masaru , Furukawa Hidemitsu 
Published: February 2020

Like any other manufacturing technology, Additive Manufacturing (AM) suffers from certain limitations. Grand challenges that hinder the use of AM in the field of sensors, actuators and energy are:

lack of materials available for AM

multi-material AM

feature size and accuracy

In order to overcome the grand challenges that hinder the use of AM in the field of sensors, actuators and energy, we have developed a universal multi-material 3D/4D printer which is capable of printing metals, thermoplastics, gels, pastes, elastomers and nanocomposites [1, 2]. The developed 3D printer is unique in that sense that it employs a screw-based extrusion system. The materials to be 3D printed (also known as feedstock) are fed into the hopper, single screw extrusion system mixes and melts the material, remove any air bubbles, extrudes the material through a nozzle of 100 micron, ensuring 3D/4D printing without any defect [3]. By using the developed universal multi- material 3D printer we have been able to 3D/4D print Steel, Aluminium, Silver, Nickle, Cobalt, Copper, Carbon fibre based nanocomposites, Ionic gels, Titanium dioxide, various thermoplastics, Shape memory materials, Wood and Epoxies as shown in figure 1. Such type of single screw base extruder 3D/4D printer will be a new addition to the additive manufacturing process.
References:

Shiblee, Md Nahin Islam, Kumkum Ahmed, Ajit Khosla, Masaru Kawakami, and Hidemitsu Furukawa. "3D printing of shape memory hydrogels with tunable mechanical properties." Soft matter (2018). DOI:10.1039/C8SM01156G

Khosla, Ajit, et al. "Carbon fiber doped thermosetting elastomer for flexible sensors: physical properties and microfabrication." Scientific reports 8.1 (2018): 12313. https://doi.org/10.1038/s41598-018-30846-3

Shah, Shreyas, et al. "3D printing of electrically conductive hybrid organic–inorganic composite materials." Microsystem Technologies 24.10 (2018): 4341-4345. https://doi.org/10.1007/s00542-018-3781-x

Figure 1
(Invited) Microfabrication and Electrochemical Activation of Amorphous Carbon Nitride a-CNx Working Electrode Integrated in Microfluidic Chip
Authors: Horny Marie-Charlotte , Billon Florence , Siaugue Jean-Michel , Dupuis Vincent , Lazerges Mathieu , Deslouis Claude , Pailleret Alain , Gamby Jean 
Published: February 2020

a-CNx ﬁlms are well-known polarizable interface materials with a large potential window (3 V-4 V [1]) interesting electrochemical reactivity [2] and tunable chemical surfacic composition [3]. Indeed, the surface structure, surface properties, number of grafting sites available are tunable according to the atomic percentage of nitrogen in the a-CNx [4]. High surface reactivity are highly dependent on the surface state and can be affected by synthesis (by varying the Csp3/sp2 ratio), and by pre-treatment (electrochemical or plasma). In this work, we elaborated a microﬂuidic chip integrating a-CNx as working microelectrodes. In brief, a titanium/ platinum (50/500 Å) underlayer was first deposited on the glass wafer and patterned as working microelectrodes for the future thin film a-CNx adhesion and conductivity. On the top of the working electrode, a 220 nm a-CNx (x=0.12), layer was deposited with DC magnetron sputtering (time =20 min, power=200 W) with a graphite target under a ﬂow of nitrogen (PN2/Ptot =3%, Ptot =0.4 Pa). Then, a classical PDMS fluidic circuit was microfabricated and pre-treated with nitrogen plasma to favor its adhesion onto the glass slide containing the Ti/Pt/ a-CNx microelectrodes. The a-CNx microelectrodes were also electrochemically pre-treated in galvanostatic mode using 0.1 M KOH solution (anodic pre-treatment). The hydrodynamic properties of the fluidic channel a-CNx microelectrodes (as-grown and pre-treated) were screened with the [Fe(III)(CN)6]3−/[Fe(II)(CN)6]4− redox couple by cyclic voltammetry and impedance spectroscopy to provide a basis for further investigations such as the inﬂuence of a-CNx electrode pre-treatment on the DNA probe density issues in order to enhance the hybridization reaction efficiency with its specific DNA target.
[1]. A. Lagrini, C. Deslouis, H. Cachet, M. Benlahsen, and S. Charvet. Elaboration and electrochemical characterization of nitrogenated amorphou scarbon ﬁlms, Electrochem. commun., 6(3) (2004) 245–248.
[2]. G Adamopoulos, C Godet, C Deslouis, H Cachet, A Lagrini, and B Saidani. The electrochemical reactivity of amorphous hydrogenated carbon nitrides for varying nitrogen contents: the role of the substrate. Diam. Relat. Mater.,12 (2003) 613– 617.
[3]. R A Medeiros, A Benchick, R C Rocha-Filho, O Fatibello-Filho, B Saidani, C Debiemme-Chouvy, and C Deslouis. Simultaneous detection of ascorbic acid and dopamine with electrochemically pretreated carbon nitride electrodes: Comparison with boron-doped diamond electrodes. Electrochem. commun., 24 (2012) 61–64.
[4]. M Faure, F Billon, A M Haghiri-Gosnet, B Tribollet, C Deslouis, A Pailleret, and J. Gamby. Influence of the atomic nitrogen content in amorphous carbon nitride thin films on the modulation of their polarizable interfaces properties. Electrochim. Acta, 280 (2018) 238-247.
Fabrication of Flexible Energy Storage Device Using MnO2@Graphene Composite Synthesised By Electrochemical Exfoliation Method
Authors: Das Himadri Tanaya 
Published: February 2020

Conventional energy storage devices have relied upon the ability of the electrochemically active materials to store the charge in the wide potential region with high Coulombic efficiency. Transition metal oxides are considered as ideal electrode materials in various energy storage devices, owing to their unique features, namely, high theoretical specific capacity; pseudocapacitive nature and ability to deliver large energy and power density. However, it suffers from many drawbacks, such as, low electronic conductivity and capacity fading with number of cycles. To address these shortfalls metal oxides are, usually, embedded within a conductive carbon-based matrix (for example graphene). The use of graphene would afford easy pathway for electron movement and increases the surface area for higher interaction of active electrode materials with electrolyte. Subsequently, graphene based transition metal oxides composites have attracted active research pursuits in synthesizing the low cost effective electrode materials for energy storage devices.
In this work, we report a facile and economic approach to produce manganese oxide nanorods amalgamated on the graphene sheets (MnO2@G) powders with an aim to achieve improved electrochemical activity. This electrochemical exfoliation strategy demonstrates a synthesis scheme from the graphite sheets at a constant voltage of 10 V in the MnSO4 bath solution, the outcome of which are the black shinny flaky powders. The crystallinity MnO2@G powders' was confirmed by XRD analysis. The TEM reveals the incorporation of MnO2 nanorods on the exfoliated few layers of graphene nanosheets. The physiochemical and electrochemical properties were tuned by varying concentrations of MnSO4 solutions. Interestingly, it was found that the yield of graphene as well as the performance of MnO2@G governed by the concentrations of salt solution. The degree of graphitisation in the as prepared materials was investigated by depth analysis in the Raman spectroscopy. Further, the electrochemical performances of MnO2@G were examined by cyclic voltammetric, charge-discharge and electrochemical impedance spectroscopy studies in a three electrode set-up. It was discovered that the MnO2@G composite prepared using 0.1 M MnSO4 solution has a delivered better electrochemical performance. To realise the practical applicability of the MnO2@G composite, flexible light-weight solid-state prototype asymmetric supercapacitor was fabricated using MnO2@G as positive and graphene as negative electrode. The fabricated devices exhibited ample storage capacity along with high energy density and powder density which were capable of powering consumer electronics applications. Thus, in the present work we have developed a cheap and effective electrochemical preparation of exfoliated MnO2@G composites in high yield. This scheme could serve as precedent to the development of potential electrode materials for energy storage devices.
Promoting the Cyclic Performance and Boosting Li+transport of LiV3O8 Via Ca Doping
Authors: Xu Yinsheng 
Published: February 2020

As one of the most promising cathodes for rechargeable Lithium ion battery, LiV3O8 commonly suffers from inevitably complicated phase transitions and sluggish kinetics. Here, we develop a Ca doping technique to
tackle this long-standing issue of instability and improve the rate performance of LiV3O8. The dopants are found to reside in the Li site ofLiV3O8, where works as a pillar to increase the a axis distance facilitating Li diffusion, stabilizing the structure and suppressing the phase transition during cycling. This doped LiV3O8 displays an exceptionally high capacity of 280 mAh g-1, cyclability with 87% capacity retention over 100 cycles and significantly enhanced rate capability.