bluuebunny/crossref_metadata_2025_split huggingface dataset:
TiP2O7 Exhibiting Reversible Insertion of Sodium Ions in an Aqueous Environment
Authors: Yee Grace , Whitacre Jay , Shanbhag Sneha , Chang Jiang , Carlisle Kristen 
Published: February 2020

Aqueous sodium ion batteries are attractive for large-scale energy storage due to their low cost, intrinsic safety and environmental friendliness [1,2]. A key challenge in designing aqueous batteries is creating electrode pairs that operate within the stable potential window of water, with anode material selection being particularly challenging. Furthermore, good materials for sodium ion cycling are limited [2,3]. TiP2O7 presents a promising anode material due to its lower intercalation/deintercalation potentials, allowing for more optimized use of an aqueous electrolyte’s stability window [1-3]. TiP2O7 is typically reported to exclusively cycle lithium ions, showing no capacity in sodium aqueous electrolytes in cyclic voltammetry tests [3]. One report demonstrated that a low temperature polymorph of TiP2O7 exhibits reversible cycling of sodium ions in an organic electrolyte [4].
In this work, the reversible insertion of sodium ions in TiP2O7 as the anode material in an aqueous battery is demonstrated. Several polymorphs of TiP2O7 are synthesized using a high temperature solid-state route and a low temperature sol gel route. In addition to physical characterization, the materials are electrochemically characterized in an aqueous 1M Na2SO4 electrolyte against Na0.44MnO2 cathode material. While no capacity for sodium ion cycling is reflected in cyclic voltammetry tests of these TiP2O7, all polymorphs exhibited reversible cycling of sodium ions in constant current galvanostatic cycling with potential limitation. To our knowledge, this is the first report of solid-state synthesized TiP2O7 reversibly cycling sodium ions. Specific capacity is found to be positively correlated with both crystallite size and lattice parameter. A full cell rate study with three electrode data in aqueous Na2SO4 electrolyte is presented.
Acknowledgments
This work is supported by Carnegie Mellon University and Aquion Energy Inc.
References
[1] W. Wu, S. Shanbhag, A. Wise, J. Chiang, A. Rutt, J. Whitacre, “High Performance TiP 2 O 7 Based Intercalation Negative Electrode for Aqueous Lithium-Ion Batteries via a Facile Synthetic Route,” Journal of The Electrochemical Society, 162 (2015).
[2] H. Wang, K. Huang, Y. Zeng, S. Yang, L. Chen, “Electrochemical properties of TiP 2 O 7 and LiTi 2 (PO 4 ) 3 as anode material for lithium ion battery with aqueous solution electrolyte,” Electrochemica Acta, 52 (2007) 3280-3285.
[3] L. Chen, Q. Gu, X. Zhou, S. Lee, Y. Xia, Z. Liu, “New-concept batteries based on aqueous Li + /Na + mixed-ion electrolytes,” Scientific Reports, 3 (2013).
[4] P. Senguttuvan, G. Rousse, J. Oro-Sole, J.M. Tarascon, M.R. Palacin, “A low temperature TiP 2 O 7 polymorph exhibiting reversible insertion of lithium and sodium ions,” Journal of Materials Chemistry A, 1 (2013).
(Electrodeposition Division Early Career Investigator Award Address) Magnetocapacitive Carbon Nanocomposites
Authors: Zhu Jiahua 
Published: February 2020

The global energy supply is transforming from conventional fossil energy to sustainable energy. Sustainable energy species, for example, solar, wind, and hydro energy, are in an unsteady state and fail to provide a stable energy supply. Energy storage units can collect these unsteady state energies and output as stable energy supply. However, current energy storage units face significant challenges to provide both high-energy density and high-power density. To achieve high energy storage performance of electrochemical capacitor, existing research efforts mainly focus on (1) synthesizing new electrode materials to enlarge specific capacitance, and (2) designing asymmetric capacitor configuration and utilizing organic electrolytes to expand the working potential range. Without changing any internal components, we recently observed a significant capacitance enhancement of up to 155% by solely applying a small external magnetic field (0.072 Tesla). The magnetic field induced capacitance change is called magnetocapacitance.
In this talk, small magnetic field induced capacitance change on carbon nanocomposites will be discussed. Two processes, conventional- and microwave- annealing, were introduced to manufacture desired electroactive carbon nanocomposites decorated with pseudoactive metal oxide nanostructures (for example, Fe2O3, NiO and Co3O4). Their magnetocapacitances will be measured and compared. The proposed mechanisms will be interpreted by capacitor internal resistance change (solution resistance, charge transfer resistance and leakage resistance), which are based on Magnetohydrodynamics and Magnetoresistance phenomena. These findings will have significant impacts on processes involving proton and electron transfer as used in Li ion battery, fuel cells, electrochemical and biological sensing, and electrocatalytic CO2 reduction. The perspective for future projects will be discussed as well.
(Invited) Electrochemical Deposition of Carbon Materials in Molten Salts
Authors: Wang Dihua , Gao Muxing , Chen Zhigang , Deng Bowen , Yin Huayi , Xiao Wei , Mao Xuhui 
Published: February 2020

Molten salt CO2 capture and electrochemical transformation (MSCC-ET process) into carbon and oxygen [1] is a promising way for effectively capturing and utilizing the greenhouse gas. In the process, CO2 is first absorbed by the molten salt to form carbonate ions and then they are reduced to carbon on the cathode. There are several advantages of the process over others: (1) high current density; (2) high selectivity and current efficiency; (3) lower decomposition potential and overpotential for both anode and cathode reaction; (4) value-added product of functional carbon; (5) simple and cost-affordable electrodes; (6) scalability; (7) environmental friendly and etc. Although electrodeposition of carbon in molten carbonates was first reported in 1960s [2], it is very recent that it becomes a research focus due to the great concern of global warming. There is some new advancement in the field either on the fundamental aspects or practical applications in recent years. Herein, we report the absorption kinetics and thermodynamics of CO2 by molten salt under different temperature and partial pressure of CO2 using a home-made CO2 absorption testing system [3]. The absorption capacity of dissolved Li2O was 0.835 molCO2/molLi2O at 723 K in Li2O containing ternary eutectic carbonate. The mass transfer of carbonates was the dominating factor governing the rate of static absorption. The reduction mechanism of cathode and anode was evaluated by in-situ gas analyzing. There was no CO was detected at 723K over a wide potential range. The reduction kinetics of carbonate was further investigated by cyclic voltammetry and steady-state polarization curve measurements under different temperature and the rate-limiting step was determined. Furthermore, carbon materials with different morphology and composition were obtained under different electrolysis temperature, cell voltage or in different molten salts. It was found that the MSCC-ET process can not only capture CO2 but also absorb SO2 in flue gas. Sulfur doped carbon was obtained by using flue gas as raw material and zero SO2 emission was realized in the process. The obtained carbons show very high specific capacitance and specific capacity as electrode materials for supercapacitor and lithium ion battery, respectively [4].
References:
[1] H.Y. Yin, X.H. Mao, D.Y. Tang, W. Xiao, L.R. Xing, H. Zhu, D.H. Wang, D.R. Sadoway, Energy Environ. Sci., 2013, 6, 1538-1545.
[2] M.D. Ingram, B. Baron, G.J. Janz, Electrochim. Acta, 1966, 11 ,1629-1639.
[3] BW Deng, JJ Tang, XH Mao., YQ Song, H Zhu, W Xiao, and DH Wang, Environ. Sci. Technol., 2016, 50, 10588–10595
[4] JJ Tang, BW Deng, F Xu, W Xiao, DH Wang, Journal of Power Source ，2017，341, 419-426
(Invited) Atomic Layer Deposition of Nanoalloys of Noble and Non-Noble Metals
Authors: Ramachandran Ranjith K. , Dendooven Jolien , Filez Matthias , Galvita Vladimir V. , Poelman Hilde , Solano Eduardo , Minjauw Matthias M. , Marin Guy B. , Detavernier Christophe 
Published: February 2020

Bimetallic nanoparticles (BMNPs) play a pivotal role in optical, magnetic and electronic applications, and are true workhorses during the catalytic transformation of chemicals. In particular, supported Pt nanoparticles alloyed with In, Ga or Sn are highly selective catalysts for the dehydrogenation of propane to propylene. It is well established that the size and composition of the nanoparticles strongly impact the catalytic properties and performance. Yet, conventional synthesis strategies lack proper control over the nanoparticle morphology and composition. ALD has proven its potential for the size and composition controlled synthesis of supported BMNPs, but has to date only been applied for the synthesis of binary noble metal nanoparticles like Pt-Pd, Pt-Ru and Pd-Ru BMNPs. Extension of this approach to BMNPs containing non-noble metals has so far been hampered by unfavorable ALD chemistries to deposit non-noble metals in their elemental state. As a consequence, a strong need has arisen to develop alternative ALD-strategies which can deal with non-noble metals also.
We report a new ALD based procedure for the tailored synthesis of BMNPs containing a non-noble metal next to a noble metal (ACS Nano, 2016, 10, 8770–8777), here exemplified for nanoalloys containing In as non-noble and Pt as noble metal. Figure 1a schematically describes the steps involved in the fabrication process of the Pt-In BMNPs. Thin layers of In2O3 and Pt are sequentially deposited by ALD, yielding a Pt/In2O3 bilayer structure. These bilayers are then subjected to a temperature programmed reduction (TPR) in hydrogen to induce the formation of Pt-In nanoalloys. The BMNP formation during TPR was followed by in situ XRD measurements (Figure 1b) and was further confirmed by ex situ XAS (Figure 1c) and SEM measurements. The composition of the formed bimetallic alloys can be tuned by controlling the ratio of the deposited thickness of Pt to the thickness of In2O3. Figure 2a presents the relation between the as-deposited Pt/(Pt+In) atomic ratio and the alloy phase(s) obtained after TPR. In addition, our method enables tuning of the particle size with high precision in a range from 1 to 30 nm by changing the total thickness of the ALD-grown Pt/In2O3 bilayer (Figure 2b). Tuning of the particle size while keeping the composition the same can thus be achieved by scaling the layer thicknesses of the Pt and In2O3 layers while keeping the Pt/(Pt+In) atomic ratio constant.
Finally, successful BMNP synthesis was achieved on mesoporous silica, resulting in high surface area nanocatalysts which showed promising high activity for propane dehydrogenation.

Figure 1
(Invited) Zintl Phase Thermoelectrics: Engineering Transport through Crystal Chemistry
Authors: Zevalkink Alexandra 
Published: February 2020

Intermetallic Zintl phases form complex composite structures characterized by covalently-bonded polyanions stabilized by the surrounding cations. The Zintl polyanions occur in an astounding variety of forms, including isolated 0-dimensional clusters, 1-D chains, and 2-D slabs, making this an ideal class of compounds to study structure-property relationships in complex semiconductors. AM
2
X
2 compounds in the CaAl2Si2 structure type are one of the most successful classes of Zintl thermoelectrics - particularly in light of recent reports of zT ~ 1.5 in n-type MgMg2Sb2. This talk will explore the role played by the defect chemistry of AM
2
X
2 compounds. We have shown both experimentally and using first principles calculations that the low formation energy for cation vacancies in this structure type enables tuning of the electronic properties via either alloying or by directly varying the cation content. In addition, by using high pressure, we have investigated the transport properties of AM
2
X
2 compounds synthesized using high pressure. While AM
2
X
2 compounds in the CaAl2Si2 structure are typically narrow gap semiconductors, those in the related tetragonal BaZn2P2 structure type are exclusively metals or semimetals and are known to exhibit superconductivity. In the first example of a phase transition between these two technologically important structures types, we show that SrAl2Si2 (trigonal CaAl2Si2-type structure at ambient pressure) can be obtained as a metastable phase in the tetragonal BaZn2P2 structure type by employing high-pressure, high-temperature synthesis. Our study shows that the changes in the electronic density of states lead to the emergence of phonon-driven superconductivity in the tetragonal polymorph. By accessing structural motifs that are not thermodynamically stable at ambient conditions, we are thus able to directly investigate the relationship between structure and electronic properties in AM
2
X
2 Zintls.
Design and Application of Strained Interface Heterostructures in Resistive Switching Devices
Authors: Bowman William J , Schweiger Sebastian , Pfenninger Reto , Izadi Ehsan , Darbal Amith , Crozier Peter A , Rupp Jennifer L. M. 
Published: February 2020

Resistive switching memories operating on ionic carriers are considered as next generation storage-class memories to replace electronic transistor memory technologies. Strain engineering is a relevant optimization route to introduce defects for resistive switching materials based on mixed ionic-electronic conducting oxides. Interfacial strain control of electrical conductivity [1] was reported for sideways-contacted Gd0.1Ce0.9O2-δ|Er2O3 (GCO|ERO) microdot heterostructures with alternating monolayers of insulating ERO and mixed-conducting GCO, whose lattice mismatch yielded compressive strain in the GCO layers.
We use ionic heterostructures as strain-modulated memristive devices based on the model system GCO|ERO to tune the property of “memristance.” Modulation of interfacial strain and interface count is used to engineer the Roff/Ron ratio and the system’s persistence [2]. By employing Raman microscopy and TEM on heterostructures with a range of monolayer thickness down to 3-5 nm, we observed an evolution in the near-order crystal symmetry from a mostly relaxed isotropic structure—present in devices with ~100 nm monolayers, to predominantly anisotropic strain fields in devices with monolayers of several nm. Resistive switching in these model systems is discussed.
Via sideways contacting, unique model experiments isolate the impact of electroforming on a symmetric device, revealing that reversing the electroforming polarity mirrors the memristive response about zero volts without affecting memristance. In addition to GCO|ERO we explore alternative insulating straining oxides which impart varying degrees of tensile strain on GCO. Strain mapping via TEM precession-enhanced electron nanodiffraction resolves lattice distortion in these systems with nanometer spatial resolution, and strain data are correlated with interface composition and electronic structure measured by electron energy-loss spectroscopy, providing atomic-level insights regarding strained heterostructure design [3].

Acknowledgements

We acknowledge ScopeM at ETH Zürich and the John M. Cowley Center for High Resolution EM at ASU, and thank the staff for their support.

References

[1] S. Schweiger, M. Kubicek, F. Messerschmitt, F. Murer, J.L.M. Rupp. ACS Nano 8 (2014) 5032
[2] S. Schweiger, R. Pfenninger, W.J. Bowman, U. Aschuauer, J.L.M. Rupp. Adv. Mat. (In press)
[3] W.J. Bowman, S. Schweiger, E. Izadi, A.D. Darbal, J.L.M. Rupp, P.A. Crozier. (In preparation)
(Keynote) Current and Future Directions in Power Electronic Devices and Circuits Based on Wide Band-Gap Semiconductors
Authors: Kizilyalli Isik C. , Cunningham Daniel W , Manser Joseph S. , Carlson Eric P 
Published: February 2020

Electricity generation currently accounts for 40% of primary energy consumption in the U.S., and over the next 25 years is projected to increase more than 50% worldwide. Electricity continues to be the fastest growing form of end-use energy. Power electronics are responsible for controlling and converting electrical power to provide optimal conditions for transmission, distribution, and load-side consumption. Estimates suggest that the fraction of electricity processed through power electronics could be as high as 80% in the US by 2030 (including generation and consumption), approximately a twofold increase over the current proportion. Development of advanced power electronics with exceptional efficiency, reliability, functionality, and form factor will provide the U.S. with a competitive advantage in deployment of advanced energy technologies. Additionally, widespread integration of innovative converters offers substantial energy saving opportunities both directly, by inherently more efficient designs, and indirectly, by facilitating higher levels of adoption for fundamentally higher performing materials. High impact opportunities exist across a variety of applications, including power supplies, motor drives, automotive (including DC fast charging infrastructure), data centers, and aerospace, as well as grid and distributed energy resources (wind, solar PV, MV/HVDC, FACTS). Fast switching power semiconductor devices are the key to increasing the efficiency and reducing the size of power electronic systems. For the last three decades, silicon power devices (MOSFETS, IGBTs, and diodes) have dominated the power device market. During this time there have been tremendous improvements in silicon power device performance. However, these devices are now approaching the physical limits of silicon. Alternative wide-band gap semiconductor materials, such as silicon carbide (SiC) and gallium nitride (GaN) are enabling a new generation of power devices that will far exceed the performance of silicon-based devices. Wide band-gap semiconductors enable continued improvement of the efficiency and reduced system size of power electronics. In this presentation, future directions in emerging wide bandgap semiconductor devices will be discussed. Furthermore, we will discuss the development and deployment of a new class of efficient, lightweight, and reliable power converters through transformational advances in circuit topologies, advanced control and drive electronics, and innovative packaging.
(Invited) Engineering Metal Oxide Semiconductors for Flexible Electronics
Authors: Martins Rodrigo 
Published: February 2020

Metal oxides are contributing for generating a free real state electronics that is able to add new electronic functionalities onto surfaces, which currently are not used in this manner and where silicon cannot contribute [1,2]. The already high performance developed n- and p-type TFTs have been processed by physical vapor deposition (PVD) techniques like rf magnetron sputtering at room temperature which is already compatible with the use of low cost and flexible substrates (polymers, cellulose paper, among others). Besides that a tremendous development is coming through solution-based technologies very exciting for ink-jet printing. In this presentation we will review some of the most promising new technologies for n- and p-type thin film transistors based on oxide semiconductors and its currently and future applications.
Moreover, we will refer also to the exploitation of cellulose-based hydrogel as dielectric in TFT on paper as well as to the engineering procedures governing the selection or development of printable nanostructured metal oxide nanoparticles for chromic, photovoltaic, photocatalytic, sensing, electrolyte-gated TFTs, and power storage applications.

Figure 1
Amorphous Nanorod Boron As Anode Material for Lithium Ion Batteries at Room Temperature
Authors: Lau Miu Lun , Deng Changjian , Barkholtz Heather Marie , Xu Tao , Liu Yuzi , Wang Hao , Connell Justin Grant , Parrish Riley , Smith Kassiopeia , Xiong Hui (Claire) 
Published: February 2020

We report an amorphous boron nanorod anode material for lithium ion batteries prepared through smelting non-toxic boron oxide in liquid lithium. Boron in theory can provide capacity as high as 3099 mAh g-1 by alloying with Li to form B4Li5.1 However, experimental studies of boron anode were rarely reported for room temperature lithium-ion batteries. Among the reported studies the electrochemical activity and cycling performance of bulk crystalline boron anode material are poor at room temperature. In this work, we developed amorphous nanostructured one-dimensional (1D) boron material aiming at improving lithium ion diffusion in boron at room temperature. The amorphous boron nanorod anode exhibited, at room temperature, a reversible capacity of 170 mAh g-1 at a current rate of 10 mA g-1 between 0.01 and 2 V. The anode also demonstrated good rate capability and cycling stability. Lithium storage mechanism was investigated by both sweep voltammetry measurements and galvanostatic intermittent titration technique (GITT). The sweep voltammetric analysis suggested that the contributions from lithium ions diffusion into boron as well as the capacitive process are 57% and 43%, respectively. Results from GITT indicated that the discharge capacity at higher potentials (> ~ 0.2 V vs, Li/Li+) could be ascribed to a capacitive process and at lower potentials (< ~0.2 V vs, Li/Li+) to diffusion control. Solid state nuclear magnetic resonance (NMR) measurement further confirmed that the capacity is from electrochemical reactions between lithium ions and the amorphous boron nanorod.
References:
1. M. Worle and R. Nesper, Angew Chem Int Edit, 2000, 39, 2349-2353.

Figure 1
(Invited) Solution-Processed Charge Transfer Doping of Transition-Metal Dichalcogenides (TMDs) with Redox-Active Molecules
Authors: Zhang Siyuan , Hacker Christina A. , Pookpanratana Sujitra 
Published: February 2020

The promise of flexible, stretchable, and transparent circuitry has driven intense research in carbon-based and two-dimensional (2D) material-based electronics, such as organic semiconductors, graphene and transition-metal dichalcogenides (TMDs). For integrated circuits applications consisting of CMOS, p-n diodes and other logic components, both n-type and p-type semiconductors are equally important. Controlled doping of two-dimensional semiconductors promises a powerful tool to tailor their electrical and optical properties toward next generation electronic and optoelectronic devices. In this study, solution-processed charge transfer doping of four transition metal dichalcogenides MX2, where M is either Mo or W and X either S or Se, is achieved using molecular reductants and oxidants. Sub-hundred-micron size (ca. 50 to 100 μm) of MX2 were exfoliated via gold-mediated transfer technique.1 The doping type and strength can be conveniently controlled by the redox potential of the metal-organic molecules, the concentration of dopant solutions and treatment time.2 The doping effects are observed through the evolution of electrical characteristics of MX2 field effect transistor devices. I-V characteristics of MX2 field effect transistor (FET) devices treated with both p- and n-dopants are measured, from which the charge carrier densities induced by the doping were estimated. Detailed physical characterizations including photoemission (UPS and XPS), Raman and photoluminescence (PL) spectroscopy are used to study the doping effect and to understand the underlying mechanism. The origin of the doping is attributed to the shift of Fermi level and work function through the charge transfer process between molecular dopants and 2D semiconductors. Overall, we have demonstrated a solution-based charge transfer doping using molecular oxidants and reductants to p- or n-dope several 2D semiconductors. This technique provides a simple yet effective route to tailor the band structure of the 2D materials, and control the resulting electrical and optical properties.
References
(1) Desai, S. B.; Madhvapathy, S. R.; Amani, M.; Kiriya, D.; Hettick, M.; Tosun, M.; Zhou, Y.; Dubey, M.; Ager, J. W.; Chrzan, D. Adv. Mater. 2016, 28, 4053.
(2) Tarasov, A.; Zhang, S.; Tsai, M. Y.; Campbell, P. M.; Graham, S.; Barlow, S.; Marder, S. R.; Vogel, E. M. Adv. Mater. 2015, 27, 1175.