bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enhanced Li Metal Anode Stability By 3D Porous Nickel Substrate
Authors: Yu Lu , Canfield Nathan L , Chen Shuru , Lee Hongkyung , Engelhard Mark H , Li Qiuyan , Liu Jun , Xu Wu , Zhang Ji-Guang 
Published: February 2020

Li metal anode is desirable for high energy density batteries because of its high theoretical specific capacity and lowest redox potential. However, its applications have been plagued for decades due to problems such as dendritic Li growth and low Li plating/stripping Coulombic efficiency (CE). The three-dimensional propagation of Li dendrites could penetrate the separator leading to safety concerns. In addition, Li dendrites could lead to dynamic breaking and forming of the solid-electrolyte interphase layer (SEI), causing fast electrolyte consumption and rapid capacity fading.
To address the above challenges, recently studies have demonstrated the effectiveness of 3D metal current collectors in suppressing Li dendrites and stabilizing the Li metal anode [1]. It has been suggested that the positive effect is mainly due to the high surface area of the 3D structure, which lowers the local current density and suppresses Li dendrites. Also the Li electrodeposits are accommodated inside the 3D current collector and this reduces the Li volume expansion. Although these reasons likely explain the benefits of using 3D current collectors, in-depth understanding of how 3D current collectors improve the SEI layer properties is not available. Gaining such knowledge is important for understanding the fundamental mechanism and designing effective 3D current collectors to stabilize Li metal anode.
In this study, we investigated the fundamental mechanism by which a 3D porous Ni current collector improves Li metal anode stability. Using a combination of galvanostatic intermittent titration technique and scanning electron microscopy, it was found that the 3D porous Ni current collector can effectively suppress the “dead” Li formation and forms a compact and robust surface layer. This surface layer protects Li metal and Li ion transport through this layer is unimpeded over cycling. However, without the 3D porous Ni current collector, significant amount of “dead” Li is accumulated on the Li metal over cycling, which leads to mass transport limitations. X-ray photoelectron spectroscopy results further revealed the differences in the SEI layer composition on the Li metal embedded in porous 3D Ni substrate and the 2D Li metal substrate.
1. S. S. Chi, Y. Liu, W. L. Song, L. Z. Fan and Q. Zhang, Adv. Func. Mater., 27, 1700348 (2017).
Rechargeable Zinc-Ion Batteries Based on Deep Eutectic Solvent
Authors: Kao-Ian Wathanyu , Kheawhom Soorathep 
Published: February 2020

The intermittent characteristic of renewable energy sources leads to a significant challenge in energy generation. Considerable efforts have been made to explore viable solutions, with rechargeable batteries standing out among various energy storage systems. Recently, lithium-ion batteries (LIBs) are widely used in various energy storage devices. However, the high cost, inherent safety risks, and limited lithium resources seem to restrict their large-scale application. Therefore, different new rechargeable battery systems such as aluminum-ion, magnesium-ion, and zinc-ion batteries (ZIBs) have been developed. Among these, rechargeable ZIBs with high safety, abundant electrode materials, high theoretical capacity, environmentally benignity, and low-cost, have received extensive attention.
Typically, a ZIB system consists of a host material capable of storing zinc ions as the cathode, zinc metal as the anode. The cathode material becomes the primary limitation for battery performance and manganese dioxide (MnO2) is considered the most promising candidate due to its natural abundance, environmental benignity and low-cost. Generally, mild aqueous electrolyte made of sodium sulfate (Na2SO4) solution are implemented. However, the narrow electrochemical stability window of aqueous electrolytes has limited the operating voltage of the host materials. Thus, deep eutectic solvents are introduced to address this issue. Nevertheless, the mechanism of zinc ion storage and the reason for the capacity fading in ZIB system in deep eutectic solvents have not been thoroughly clarified.
In this work, we present a rechargeable ZIB that is composed of a zinc anode prepared from nickel foam supported zinc, a cathode made of stainless steel mesh supported MnO2/carbon film and an electrolyte made of a non-flammable deep eutectic solvent (ethylene glycol/(2-hydroxyethyl) trimethylammonium chloride). ZnCl2 additive in the electrolyte was examined, and the optimal ratio of ZnCl2 was determined. The fabricated battery operated through the electrochemical deposition and dissolution of zinc at the anode, and intercalation/de-intercalation of zinc ions in the MnO2 structure. The fabricated battery exhibited a large capacity of about 200 mAhg-1 and a charge efficiency of approximately 98%. The cathode was found to withstand more than 2,000 cycles without significant capacity decay. The results demonstrated a deep eutectic solvent-based ZIB and offered a fundamental basis for understanding the electrochemical intercalation chemistry of zinc ions in a deep eutectic solvent.

Figure 1
Water-Lubricated Intercalation in V2O5·nH2o for High-Capacity and High-Rate Aqueous Rechargeable Zinc Batteries
Authors: Yan Mengyu , He Pan , Mai Liqiang , Yang Jihui 
Published: February 2020

Low cost, environmentally friendly aqueous Zn batteries have great potential for large-scale energy storage. In our previous work, we found that the intercalation of zinc ions in the cathode materials is challenging and complex [1, 2]. In this talk, we will try to clarify it by showing the critical role of structural H2O on Zn2+ intercalation into the V2O5 framework [3].
Our latest results demonstrate that the H2O solvation of Zn2+ largely reduces its effective charge and thus its electrostatic interactions with the V2O5 framework, effectively promoting the diffusion of solvated Zn2+. Benefited from the ‘lubricating’ effect, the aqueous Zn battery shows a specific energy of ~ 144 Wh kg-1 at 0.3 A g-1. Meanwhile, it can maintain an energy density of 90 Wh kg-1 at a high power density of 6.4 kW kg-1
(based on the cathode and 200% Zn anode), making it a promising candidate for high-performance, low-cost, safe, and environmentally friendly energy storage device. Such a ‘lubricating’ effect in Zn batteries could be applicable to other multivalent metal ion-based batteries for further improving the energy storage performance, and could also shed light on discovering new battery materials.

Reference
[1] H. Pan, Y. Shao, P. Yan, Y. Cheng, K. S. Han, Z. Nie, C. Wang, J. Yang, X. Li, P. Bhattacharya, Nature Energy
2016, 1, 16039.
[2] P. He, M. Yan, G. Zhang, R. Sun, L. Chen, Q. An, L. Mai, Advanced Energy Materials
2017, 7.
[3] M. Yan, P. He, Y. Chen, S. Wang, Q. Wei, K. Zhao, X. Xu, Q. An, Y. Shuang, Y. Shao, K. T. Mueller, L. Mai, J. Liu, J. Yang, Advanced Materials, 1703725, doi: 10.1002/adma.201703725.
Transition Metal Segregation and Phase Transformations on the Surfaces of Layered Li(Ni1-x-yMnxCoy)O2 (NMC) Cathode Materials for Li-Ion Batteries
Authors: Garcia Juan , Han Binghong , Key Baris , Vaughey John T. , Dogan Fulya , Iddir Hakim 
Published: February 2020

Nickel-rich layered oxide cathode materials have seen widespread deployment due to their high gravimetric capacity and high average discharge voltage. However, achieving this high capacity requires charging voltages above the potential at which the electrolytes decompose at the cathode surface (>4.5 V vs. Li/Li+), which leads to impedance rise and capacity loss. Furthermore, the reduction of the transition metals and oxygen loss produces a phase transformation that might be detrimental to the electrochemical performance. One strategy to stabilize this interface and improve the cycling of cathode materials is by the use of a surface coating. In this talk, we present recent Density Functional Theory (DFT) efforts aimed at gaining insights on the processes occurring at the cathode surfaces and the effect of alumina coating. It will be shown that Ni and Co possess distinctive roles in the formation of surface segregation layers (SRLs) on Li(Ni1-x-yMnxCoy)O2 NMCs. The results show that Al prefers to be surrounded by Co and Ni cations in the transition metal layers of NMC structures. The existence of Mn in the transition metal layer can therefore hinder the intercalation of Al from the surface to the bulk of the NMC particles. A discussion on the thermodynamics that govern such processes will be given.
The authors gratefully acknowledge support from the U. S. Department of Energy (DOE), Vehicle Technologies Office. Computer time allocations at the Argonne's Laboratory Computing Resource Center, is gratefully acknowledged. This research also used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. Argonne National Laboratory is operated for DOE Office of Science by UChicago Argonne, LLC, under contract number DE-AC02-06CH11357.
The U.S. Government retains for itself, and others acting on its behalf, a paid-up, nonexclusive, irrevocable worldwide license in said article to reproduce, prepare derivative works, distribute copies to the public, and perform publicly and display publicly, by or on behalf of the Government.
Toward a Dendrite Free, Powder Compact-Based Solid Electrolyte Lithium Metal Battery: Interfacial Modification
Authors: Zhao Ran , Gebhardt Ryan , Whale Alison , Hu Guantai , Martin Steve W 
Published: February 2020

Owing to its high energy density and light weight, Li-ion batteries have taken away over half of the worldwide rechargeable battery market. However, the safety issues of Li-ion batteries that originate from the combustible organic electrolyte are of great concern recently. Solid-state batteries using powder compact solid electrolytes (PCSE) are promising options toward safer and higher energy density batteries due to the utilization of inorganic electrolyte and metal lithium as anode, however, the high solid-solid interfacial resistance between the lithium metal and the solid electrolyte is still a challenge.
In this work, we demonstrate reversible plating and stripping of dendrite-free metallic-lithium with a reduced anode/PCSE interfacial resistance by introducing a thin interfacial layer formed by heating. First, the PCSE which has an ionic conductivity of ~ 10-4 S/cm at room temperature, was synthesized by mechanical milling, and characterized using NMR, DSC, IR spectroscopy, and Raman spectroscopy. Next, the PCSE was tested in symmetric cells for electrochemical impedance spectroscopy and cycling. To address the high solid-solid interfacial resistance and short-circuiting dendrite problems, we demonstrate a simple strategy to engineer the lithium-PCSE interface by forming an in-situ interlayer via a heat treatment. The area specific resistance of 573.6 Ω/cm2 has been successfully achieved with a 0.9 mm thickness pellet under a current density of 0.1 mA/cm2. These results provide a promising PCSE membrane that can be applied to lithium metal battery and other energy storage application, such as lithium sulfur batteries.
Advanced Cycle Life Model Based on 18650 Lithium-Ion Battery Cells
Authors: Park Joonam , Byun Seoungwoo , Park Jinkyu , Appiah Williams Agyei , Ryou Myung-Hyun , Lee Yong Min 
Published: February 2020

Lithium-ion batteries (LiBs) have already become main energy storage devices for a variety of applications such as cellular phones, laptops, electric vehicles (EVs), and energy storage systems (ESSs). Because they have not only high energy density but also long cycle life performance with low self-discharging behaviour. Furthermore, the market size of EVs and ESSs is also expected to grow up exponentially in the near future. So, it is strongly required to estimate or predict long-term cycle life of LIBs under various operating conditions. However, due to time and facility limitation, it is almost impossible to confirm cycle lives for longer than 10 years and at various temperatures. That is why accelerated life testing methods and computation modeling have been spotlighted immensely. In particular, there have been reported various battery models, however, most of them did not show high accuracy to predict long-term electrochemical performance owing to the lack of in-depth analysis of LIB cells.
Hence, we attempt to build an advanced cycle life model based on physicochemical analysis data during cycling. First, hundreds of 18650 LIB cells are cycled at different c-rates, temperature, and depth-of-discharge, and their degradation behaviour will be gathered. And then, based on Newman’s works, the degradation equations about solid electrolyte interphase(SEI) growth and crack on the anode, an electrolyte depletion, and cathode electrolyte interphase(CEI) growth on the cathode, will be built and applied to this model.
Probing Electrochemical Structure-Property Relationships at Non-Porous Monolayer Electrodes of Exfoliated Graphene and MoS2 Single Layers
Authors: Walker Wesley R , Xu Luzhu , Krysiak Olga A , Pope Michael A 
Published: February 2020

The electrochemically available surface area and porosity of 2D materials is difficult to control due to the strong aggregation and restacking phenomena that occur when single layers are processed into thin or thick film electrodes. Furthermore, the distributed resistance, the potential for pore-size related effects and the uncertainty in relating estimated surface area and porosity data to the actual electrochemically accessible surface area make measurements of the intrinsic electrochemical performance of these materials difficult to assess. Ideally, electrochemical measurements are carried out on flat, polished or atomically flat electrode surfaces for the evaluation of intrinsic double-layer capacitance and electrochemical rate constants.
In this talk, we will discuss our efforts to create large-area monolayers of solution exfoliated 2D materials for electrochemical evaluation in aqueous and non-aqueous electrolytes. Using a modified Langmuir-Blodgett technique, we demonstrate the ability to create uniform and large area monolayers of graphene oxide, thermally reduced graphene oxide as well as 1T and 2H molybdenum disulfide which can be transferred to atomically flat electrode substrates such as highly oriented pyrolytic graphite. These films are found to be stable during electrochemical cycling in various electrolytes and allow us to probe electrochemical properties as a function of 2D material structure without porosity-related artifacts.
This model system has been used to probe the changes in double-layer capacitance in both aqueous and non-aqueous electrolytes for graphene-based materials as a function of defect density. It has allowed us to estimate the theoretical limits of graphene-based supercapacitors as a function of graphene “type”. More recently, this analysis has been extended to probe the intrinsic capacitance of the metallic 1T and semiconducting 2H polymorphs of MoS2 as a function of layer number to probe the charging mechanisms at play. The system also offers the ability to probe the capacitance of graphene/MoS2 heterostructures. These and future studies are expected to provide valuable insight into how we might build more energy dense supercapacitors from the optimal combination of 2D materials.
Flexible Graphite a Novel Platform for SERS Detection and Outstanding EMI Shielding
Authors: Sykam Nagaraju , Jayram Naidu Dhanpal , Mohan Rao G 
Published: February 2020

Exfoliated graphite (EG) has paying global consideration in the last decade because of the growing number of potential applications of these materials. So far, the production of EG based on binary or ternary compounds as intercalation and oxidation agents has been studied. However, the method consumes more quantity of acid, more number of compounds, time and energy. Here, we report a simple low cost one compound based rapid and efficient production of EG using microwave irradiation technique about 1min. The compressed form of EG without addition of any binder called flexible graphite sheet (FGS). As fabricated FGS shows outstanding Surface Enhanced Raman spectroscopy (SERS) detection as well as electromagnetic interference (EMI) shielding. FGS demonstrates responsive SERS for R6G molecules up to detection limit of 10-7 mol/L without any nanoparticle incorporation. The total electromagnetic interference (EMI) shielding effectiveness (SET) of – (96-84) dB was observed for FGS in the frequency region of 5-12GHz. These are the highest reported values for both (EMI shielding and detection) based on single material till today.
Keywords: Exfoliated graphite, Flexible Graphite sheet, Microwave irradiation, EMI shielding and SERS.
Conductivity Mapping in Graphene through Scattering-Type Scanning Near-Field Optical Microscopy in the Mid-Infrared and Terahertz Spectral Region with 25nm Spatial Resolution
Authors: Hartmann Nicolai F. , Gokus Tobias , Eisele Max , Huber Andreas J. 
Published: February 2020

Terahertz (THz) imaging and spectroscopy has emerged as a powerful tool for analysis of biological specimens or for studying and controlling low-energy excitations in solid-state systems [1]. One major limitation of THz spectroscopy is, however, the spatial resolution that is limited by diffraction to about 100-1000 µm, making it impossible to extract intrinsic, local material characteristics of nanoscale Graphene or other 2D-material structures or devices.
Scattering-type scanning near-field optical microscopy (s-SNOM) bypasses the diffraction limit, enabling optical measurements with extreme sub-wavelength spatial resolution of below 20 nm [2]. THz time-domain s-SNOM spectroscopy of a semiconductor static random access memory (SRAM) sample enables quantitative analysis of free carrier concentration and scattering rates of nanoscale device structures at unprecedented surface sensitivity. Similarly, THz s-SNOM measurements at single frequencies enabled highlighting highly conductive nanostructures in transistor devices [3]. Using a similar experimental concept to generate a local photo-current by THz radiation allows for studying nanoscale conductivity in a biased graphene device [4] or to characterize carrier scattering in a graphene sheet that has been encapsulated in hexagonal boron nitride (h-BN) and placed on a split metallic film [5].
Using an SRAM sample as a method to calibrate the amplitude contrast of the s-SNOM THz measurement with known free carrier concentrations the concept is extended to graphene. Single to few layer graphene on h-BN is imaged with a broadband THz pulse and reveals changing amplitude contrast independently of layer number (Fig. (a), (b), zoom in (d)). In a corresponding s-SNOM measurement carried out at 10 µm an inverted contrast can be observed (Fig. (c)). This contrast inversion is a direct consequence of the scattering frequency dependent free carrier response in graphene [6].
Extending the already established concepts of mid-IR s-SNOM imaging and spectroscopy of 2D materials [7] to the THz frequency range a plethora of fundamental and applied new insights into graphene and other 2D device structures can be expected from THz near-field nanoscopy measurements.
[1] M. Tonouchi, Nat. Photonics
2007, 1, 97; [2] F. Keilmann, R. Hillenbrand, Phil. Trans. R. Soc. Lond. A
2004, 362, 787; [3] A. J. Huber et al. Nano Lett.
2008, 8, 3766; [4] P. Alonso-Gonzalez, et al., Nat. Nanotechnol. 2016, 12, 31; [5] B. Lundeberg, et al., Science
2017, 357, 187; [6] J. Horng et al., Phys. Rev. B
2011, 83, 165113; [7] D. N. Basov et al., Science
2016, 354, 1992.

Figure 1
Hybrid PN Diode and CMOS Inverters Composed of MoTe2 Nanosheet-Amorphous in-Ga-Zn-O Thin Film
Authors: Lee Han Sol , Kwon Hyeokjae , Im Seongil 
Published: February 2020

We report a hybrid material system which couples a dry-transfer-processed p-type MoTe2 nanosheet and a conventional photolithography-patterned n-type amorphous InGaZnO (IGZO) thin-film. The PN junction diode shows a good ideality factor of 1.57 and a high ON/OFF rectification ratio of ∼3 × 104. Under illumination, our PN diode shows somewhat stable only responding to high-energy photons of blue and ultraviolet. Our CMOS inverter composed of p-MoTe2 bottom-gate field-effect transistor and n-IGZO top-gate field-effect transistors. Our 2D nanosheet – oxide thin film CMOS inverter shows high voltage gains as high as ~40 at 5 V, low power consumption less than ~ a few nW at 1 V, and ~200 μs switching speed.
Both hybrid PN junction diode and complementary (CMOS) inverters are realized by such novel hybrid material system that now opens any further possibilities toward practical applications of 2D nanosheets combined with existing technologies.

Figure 1
(Invited) Efficient Dyes with Unexpected Colors for Dye-Sensitized Solar Cells
Authors: Lin Ching-Yao 
Published: February 2020

We herein report three organic dyes with unusual colors for dye-sensitized solar cell (DSSC) indoor or outdoor applications.
The AN-11 dye is an anthracene-based dye. With a relatively simple chemical structure, AN-11 absorbs light at 528 nm and its solution appears red. Surprisingly, DSSCs sensitized with AN-11 show a very black color. We addressed this interesting phenomenon. For indoor applications, we examined a large module (active area = 26.8 cm2) sensitized with the AN-11 dye, along with the Z907 dye for comparison. Our study shows that overall efficiency (η) of the AN-11 module is superior to that of the Z907 counterpart, approaching 12% under 1000 Lux of T5 light.
The LS-01 and LS-11 dyes are air-stable bacteriochlorins with a push-pull chemical design. Photovoltaic measurements of our first generation bacteriochlorin dyes show that LS-01 (η = 4.67 %) and LS-11 (η = 5.36 %) significantly outperform the reference porphyrin dye, H2PE1, (η = 2.06 %) under one-sun irradiation. Intriguingly, the anodes sensitized with the LS-01 and LS-11 dyes give rise to pink and blue colors, respectively.
References:

S. Chakraborty, H.-C. You, C.-K. Huang, B.-Z. Lin, C.-L. Wang, M.-C. Tsai, C.-L. Liu, C.-Y. Lin* "meso-Diphenylbacteriochlorins: Macrocyclic Dyes with Rare Colors for Dye-Sensitized Solar Cells" J. Phys. Chem. C 2017, 121, 7081−7087.

C.-L. Wang, P.-T. Lin, Y.-F. Wang, C.-W. Chang, B.-Z. Lin, H.-H. Kuo, C.-W. Hsu, S.-H. Tu, C.-Y. Lin,* "Cost-effective Anthryl Dyes for Dye-sensitized Cells under One Sun and Dim Light " J. Phys. Chem. C 2015, 119, 24282−24289.

M.-C. Tsai, C.-L. Wang, C.-W. Chang, Y.-H. Hsiao, C.-L. Liu, Cheng Wei Hsu, C.-C. Wang, S.-Y. Lin, C.-Y. Lin* "A Large, Ultra Black, Efficient and Cost-effective Dye-sensitized Solar Module Approaching 12% Overall Efficiency under 1000 Lux Indoor Light", submitted.

Acknowledgments: This work was supported by the MOST, Taiwan, ROC.