bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electrodeposited Magnetoelastic Sensors for Ground Fault Current Detection
Authors: Pillars Jamin R. , Subramania Ganesh , Monson Todd , Finnegan Patrick Sean 
Published: December 2024

Magnetostrictive NiFeCo alloy films were investigated for use as sensors for ground fault current detection in photovoltaic systems. The magnetic field generated by a ground fault current applies a bias magnetic field to the magnetoelastic sensor, shifting the resonant frequency, and allowing for the detection of current in the microamp range. These are low-cost, passive sensors, that can be implemented to provide real time monitoring of PV systems and the early detection of failures in a system. Electrodepositing these films enables batch fabrication of thick (10-100µm) resonators with controlled resonant frequencies and optimization of material properties (magnetic, mechanical, and electrical) for increased sensitivity and signal amplitude.
Dopants such as boron and holmium were used to increase electrical resistivity and magnetic permeability respectively. Controlling intrinsic stress was managed through additive selection and allowed for the release of planar resonators with a multistep microfabrication process. The composition and properties of the deposited films were controlled by temperature, agitation, concentrations in the electrodeposition chemistry, current density, and a post processing anneal step. The samples were analyzed with EDS to determine the composition and XRD to look at film texture. Magnetic testing was performed using a super conducting quantum interference device (SQUID) magnetometry and vibrating sample magnetometry (VSM). Magnetostriction was measured using an optical method and correlated to material properties.

Acknowledgement

Sandia National Laboratories is a multimission laboratory managed and operated by National Technology & Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525.
Optimizing Sensitivity of Room Temperature CO2 Sensors through Co-Doped ZnO Nanorods By Magnetron Sputtering System
Authors: Soltabayev Baktiyar , Tangirbergen Abylay , Raiymbekov Yessimzhan , Nuftolla Aidarbek , Turlybekuly Amanzhol , Yergaliuly Gani , Mentbayeva Almagul 
Published: December 2024

Metal oxide semiconductors (MOS) based gas sensors have been identified as a promising solution for future applications due to their exceptional electrochemical, physical, and gas sensing properties. Due to their excellent optical and electrical features, ZnO nanostructures have become increasingly popular for gas detection applications, mainly because of their abundant availability. Despite its potential, the ZnO-based sensors have challenges such as poor selectivity and high power consumption at elevated operating temperatures. Transition metal doping, for example with cobalt depicted decent promising results in high response and selectivity of ZnO nanomaterials towards certain gasses. This study investigates the sensitivity enhancement of room temperature CO2 sensors utilizing the cobalt-doped ZnO (CZO) nanorod architecture. The CZO thin films were deposited on glass substrates using radio frequency (RF) magnetron sputtering at varying powers. Structural, morphological, and gas response properties of the CZO thin films were analyzed.
Figure 1 illustrates the evolution of resistance over time for CZO sensors when exposed to CO2 gas concentrations ranging from 1 to 500 ppm at room temperature in dry air. In this investigation, the response to gas follows a consistent linear pattern within the 1−300 ppm range. However, as the concentration rises, a noticeable deviation towards nonlinearity becomes more pronounced. The sensor exhibits a heightened response across various concentration levels: 1 (8.9), 50 (12.5), 100 (14.79), 150 (15.7), 250 (18.82), and 500 (23.52) ppm. Discrepancies in the sensor response are attributed to the distinct surface morphology inherent to each sensor type. The introduction of co-doping enhances the occurrence of point defects and oxygen vacancies within the CZO sensors. The Scanning Electron Microscopy (SEM) images reveal that the CZO material exhibits a highly organized surface morphology, characterized by densely packed spherical structures, and the cross-sectional analysis of the material shows a uniform thickness of 136 nm, indicating its potential applications in the field of sensing and detection, shown in figure 2. This study underscores the effectiveness of CZO nanorod architecture in rapidly detecting CO2 at room temperature, presenting promising avenues for environmental monitoring and sensing applications

Figure 1
Enhancing Supercapacitor Performance with Microemulsion-Based Electrolytes
Authors: Imel Adam , Arif Zulqarnain Z. , Barth Brian , Goenaga Gabriel , Zawodzinski Thomas A. 
Published: December 2024

Supercapacitors (SCs) are energy storage devices between conventional capacitors and batteries, providing essential technology for rapid energy storage and discharge. Used in applications like laptops, automotive braking systems, and hybrid vehicles, SCs offer high power densities and long cycle lives, though their energy densities are typically moderate. Enhancing SC energy density requires using non-aqueous electrolytes to extend the voltage window and increasing the active surface area of the electrodes to boost capacitance. However, non-aqueous electrolytes often struggle with ion solubility, which is crucial for forming the electric double layer that enables rapid charging and discharging. Our studies into microemulsions as novel electrolytes show potential in decoupling conductivity from soluble oil, addressing ion solubility issues, and potentially unlocking further performance enhancements.
Microemulsions are promising electrolytes for energy storage, forming thermodynamically stable, homogeneous solutions of polar and non-polar molecules. These solutions stabilize oil and water mixtures, allowing non-polar oil to adsorb to hydrophobic carbon electrodes while maintaining high conductivity from an aqueous salt solution. Importantly, microemulsion components are environmentally and biologically safe.
This presentation explores the impact of surfactants and microemulsions on electric double-layer supercapacitor performance. We employ scanning electron microscopy to monitor the porous carbon layer on the grafoil substrate. Techniques like electrochemical impedance spectroscopy, cyclic voltammetry, and constant current charge and discharge provide comprehensive insights into SC performance. Our findings indicate that choosing surfactant, cosurfactant, and oil is crucial for maximizing SC performance.
(Invited) Preparation of Boron-Doped Nanodiamond and Its Application to Aqueous Electrochemical Capacitors
Authors: Kondo Takeshi 
Published: December 2024

Boron-doped diamond (BDD) is known to be a functional electrode material that can be used in various electrochemical applications such as sensitive electroanalysis and efficient electrolysis, based on the unique electrochemical properties including wide potential window and low background current, as well as extreme physical/chemical stabilities. Usually, BDD electrodes are prepared by deposition of a polycrystalline BDD thin film on a conductive substrate. In this form, the specific surface area is too small to be used as an electrochemical capacitor. Thus, we have developed boron-doped nanodiamond (BDND) powder as a conductive diamond powder with a large specific surface area. BDND exhibits wider potential window in aqueous electrolytes than activated carbon (AC). Therefore, the BDND is expected to be used for an electrode material of aqueous EDLC with a large cell voltage.
Nanodiamond powder (primary particle size: 4 nm) was used as a substrate material for BDND. BDD was deposited on the agglomerate of dry nanodiamond powder via microwave plasma-assisted chemical vapor deposition (CVD). The as-deposited BDND was then treated by air oxidation at 425 °C to minimize sp2 carbon components to obtain BDND. Test electrode was prepared by casting an ink containing BDND on a glassy carbon disk electrode as a current collector. For an EDLC pouch cell, BDND paste containing PVDF binder was applied on the both sides of a titanium sheet current collector to form an electrode. Two electrodes with a separator in between was put in a plastic bag and aqueous electrolyte was poured in the bag to form a pouch cell.
The BDND was found to show a relatively large specific surface area of 650 m2 g−1 and good conductivity of ~1 S cm−1. CV in 1 M H2SO4 at the BDND test electrode in a three-electrode configuration showed a wide potential window of 3 V, which was significantly wider than that of an AC test electrode (1.5 V). In a symmetric two-electrode system, cell voltage of a CV in 1 M H2SO4 was found to be larger at the BDND electrode (1.8 V) than at the AC electrode (0.8 V). Therefore, wide potential window of the BDND was confirmed to be useful for creation of an aqueous EDLC with a large cell voltage. In addition, the use of saturated NaClO4 as an electrolyte was shown to be effective for an extremely large cell voltage of 2.8 V, which can further enlarge the energy and power densities of an aqueous EDLC. CV of BDND/saturated NaClO4 system exhibited a high energy density of 20 Wh kg−1 and a high power density of 104 W kg−1. Similar charge-discharge properties were also shown at EDLC pouch cells with BDND/concentrated NaClO4 system.
Impact of Cell Format, Engineering Design and Non-Active Components on EDLC Prototype Device Performance
Authors: Roberts Alexander John , Somyanonthanakun Wuttichai , Greszta Agata 
Published: December 2024

With the increasing interest and research focus on energy storage devices such as supercapacitors, a huge amount of current research looks at the discovery and development of new active materials, with their testing and assessment typically performed at the lab coin cell level. It is often the case that when reporting a new supercapacitor material, parameters such as energy and power densities are quoted based on these coin cell results with no regard for the different formulation and properties of electrodes needed in production, with ‘parasitic’ but necessary mass, volume and performance contributions of essential cell components such as current collectors, cans, separator, electrolyte etc. being ignored. This results in predictions and comparisons, often made with commercially available products, that significantly overestimate the potential of new materials in commercially relevant devices.
The reality is that the results obtained from coin cell tests on early stage formulations of electrodes, whilst essential for material screening and understanding of the underlying science, do not give a clear indication of performance in an eventual commercial device. As a material is incorporated into prototype devices that come closer to commercial devices, the role and effects of non-active materials, cell format and also cell engineering have increasingly significant effects on performance and lifetime.
This work investigates how cell format, cell engineering and non-active components can affect commercially relevant prototype device performance when the active material and electrode formulation are kept constant. Through the construction and testing of pouch and 18650 cylindrical prototype cells, the effect of cell format is discussed in terms of power, energy and ESR, with further insight given in how the results at coin cell level scale to both formats and various sized pouch cells. The potential for improving performance at device level through non-active materials is demonstrated by changing the current collector in pouch cells, with a comparison between battery grade, carbon coated and etched aluminium foils, showing a significant difference in cell lifetime and ESR and surprisingly, >50% difference in cell energy density at high power density. An example of how cell engineering design can effect performance is also presented, with the variation of number and position of tabs in 18650 cylindrical EDLCs, also comparing to an in-house developed tab-less cell design.
Optimization of Solid Electrolytes for Enhanced Battery-Supercapacitor Hybrid Devices: A Leap Toward High-Capacity Retention and Extended Lifespan
Authors: Gomez Rojas Omar , Sugimoto Wataru 
Published: December 2024

Battery-supercapacitor hybrid devices (BSHDs) are meant to fulfil the gap existing between conventional batteries and traditional supercapacitors by exhibiting high-energy and high-power densities, added to excellent cycling stabilities. Nonetheless, effectively integrating the diverse energy storage mechanisms of batteries and supercapacitors remains a significant challenge. Various approaches have been proposed to mitigate these issues ranging from developing advanced microstructures to engineering the interface between electrode|current collector or electrode|electrolyte.1

Previously, our team documented the fabrication of BSHDs capable of undergoing 3,000 charge-discharge cycles while maintaining 81% of their initial capacity.2 This work presents an upgraded iteration of BSHDs which maintains over 95% of the initial capacity and notably increasing the lifespan to over 10,000 cycles. The device in question is composed by a protected graphite anode and a solid electrolyte, composed by either an alginate polymer network or commercially available glass microfiber, with an ionic liquid (PP13-FSI; 1-Methyl-1-propylpyrrolidinium Bis(fluorosulfonyl)imide) as the ion conductive electrolyte. The improvement was achieved by conducting a thorough analysis and optimization of the solid electrolyte in response to the device’s performance during lithium-intercalation, i.e. introducing charge to the anode by forming a stable solid-electrolyte interface (SEI), added to the capability of such said anode as counter electrode during the operation of an activated carbon capacitor.
This work therefore discusses the duality between the maximum capacity obtained during the SEI formation process vs the capacity and anode potential retention during the operation of the BSHD, deep diving into the relationship of, inter alia, the thickness of the SEI formed, the increase or decrease of the ion-desolvation resistances, ionic conductivities, and activation energies versus the overall performance of the device.

References:

1F. Xing, Z. Bi, F. Su, F. Liu, Z.-S. Wu, Adv.
Energy Mater. 2022, 12, 2200594

2S. Makino a, R. Yamamoto, S. Sugimoto, W. Sugimoto, J
.
Power Sources 2016, 326, 711-716.

Figure 1
(Invited) Using Electrochemical Microscopy for Determining Ion Transfer Rates and Interphase Stability at the Electrode-Electrolyte Interface in Aqueous Batteries
Authors: Gossage Zachary Tyson , Ito Nanako , Hosaka Tomooki , Komaba Shinichi 
Published: December 2024

A variety of new electrolyte systems are emerging for improving batteries toward safer, higher abundance, and higher performing technologies. This includes notable interest in improving aqueous batteries through the development of highly concentrated electrolytes, e.g. water-in-salt electrolytes (WISEs). Generally, WISEs are safe, non-flammable electrolytes that contain a large amount of electrolyte salt (several molar). This can lead to an electrochemical stability window over 3 V while at the same time showing relatively high ionic conductivities compared with organic electrolytes. Therefore, the application of WISEs in high-power devices (batteries, electrochemical capacitors) is promising. Recently, our group and others have been developing WISE-based batteries containing alkali metal cations (Li+, Na+, K+), alkaline earth metal cations (Mg2+, Ca2+), mixed salts, and others.1,2 Such systems can show lifetimes >1000 cycles, but their energy and power densities, as well as retention are still lacking compared with commercial LIBs.3 WISE chemistries are still emerging, and more knowledge is needed to approach improved performance.
Here, we focus on improving our analysis and understanding of the interphase chemistry, i.e. the solid-electrolyte interphase or SEI, that occurs within WISEs. The SEI is thought to play a significant role in ion transfer, and therefore it can have a direct effect on the rate performance of the battery. Unfortunately, the highly concentrated environment makes analysis of interfacial ion transfer quite difficult. Here, we will discuss new analytical approaches based on scanning electrochemical microscopy (SECM) that are under development in our lab to quantify ion transfer rates and dynamics within these concentrated battery systems (Figure 1). We show new concepts based on redox mediators which enable such analyses for relevant cations (e.g. K+, Li+, etc.) as shown in Figure 1b,c. Aside from ion transfer, the SEI should also prevent continuous electrolyte decomposition, including H2 evolution, during operation. Our group has shown that SECM is a powerful in situ method for observing SEI development and properties in such highly concentrated electrolytes. We found the SEI in a highly concentrated K+ electrolyte showed similar passivating properties to the SEI found in common organic electrolytes, but the coverage across the electrode and stability needed to be improved.4 We will discuss progress on SEI structures in other concentrated WISEs, and recent strategies to improve the SEI performance.

References

1 Hosaka, T., et al., J. Power Sources, 2022, 548, 232096.
2 Hosaka, T., et al., ACS Appl. Mater. Interfaces, 2022, 14(20), 23507.
3 Droguet, L., et al., Adv. Energy Mater., 2020, 10, 2002440.
4 Gossage, Z.T., et al., Angew. Chem. Int. Ed., 2023, 62, e2023074.

Figure 1
Enhanced Specific Capacitance of Lithium Ion Capacitors By Effective Surface Functionalization for Lithiophilic Activated Carbon
Authors: Do Kyungmin , Ryu Jihyeon , Choi Minhyeok , Eom Seung-Wook , Kim Ick-Jun , Yang Sunhye 
Published: December 2024

Lithium Ion Capacitor (LIC) is a hybrid energy storage device that combines high power characteristics of Electric Double Layer Capacitors (EDLC) with high energy density features of Lithium Ion Batteries (LIB). In LICs, a graphite electrode from LIBs serves as the anode, while an activated carbon electrode from EDLCs functions as the cathode. This configuration results in higher energy density than EDLCs, improved power and cycling characteristics compared to LIBs. To supply lithium ions internally or externally as the energy source, LICs may employ techniques such as (1) Li pre-doping, (2) the use of sacrificial anodes made from Li transition metal oxides, or (3) electrodes embedded with lithium ions.
Significant research efforts are underway to enhance the resistance components and performance metrics, including energy density and output of LICs. Although methods like adding Li transition metal oxide, sintering salts, or blending with activated carbon are employed to increase internal capacity, challenges such as decreased energy density per unit weight, increased resistance from reaction by-products, or gas formation persist. During discharge, the desolvation energy of cations is higher than that of anions, and an increase in resistance components occurs at the 3 V point where ion exchange between lithium ions and anions happens.
This study focuses on minimizing resistance components in LICs by synthesizing a Li/activated carbon (Li/AC) hybrid material, which provides a Li source within the activated carbon matrix. Acid treatment introduces oxygen functional groups on the surface of the activated carbon, followed by the synthesis of lithium compounds using a Li precursor. The crystallization and growth conditions of Li ions were optimized using the thermal treatment temperatures established in previous studies. The study also conducted concentration-dependent synthesis experiments to optimize the molar concentration of the Li precursor solution. The manufactured Li/AC active materials were tested for charge and discharge cycles, Nyquist plots, and rate capability. To analyze these properties, techniques such as Brunauer Emmett Teller (BET) analysis, Transmission Electron Microscope (TEM), Scanning Electron Microscope (SEM), and Thermogravimetric Analyzers (TGA) were employed.
Development of a High-Capacity MXene Electrode for All-Solid-State Batteries
Authors: Fujita Masaki , Peeters Mathieu , Kawai Kosuke , Nomura Yuki , Okubo Masashi 
Published: December 2024

The global market of energy storage devices is growing for the large-scale applications such as electric vehicles and stationary power supplies. Lithium-ion batteries (LIBs) now dominate the market owing to their large energy density and long cycle life. However, the flammable organic electrolytes of LIBs pose intrinsic risks of fire and explosion accidents. Replacing the organic electrolytes with nonflammable inorganic solid electrolytes should solve the safety issue of LIBs, which accelerates development of all-solid-state batteries (ASSBs).
Conventional electrode materials show large volume changes upon (de)lithiation, causing interfacial failure between electrode materials and solid electrolytes in ASSBs.Consequently, lithium-ion flux is excessively concentrated on remaining solid-solid interfaces or loses accessibility to electrode materials. Although spinel-type Li4Ti5O12 shows a small volume change upon (de)lithiation, the specific capacity is not satisfactory (< 170 mAh g–1), which results in low energy densities. Therefore, electrode materials that show a small volume change with a large specific capacity is required to develop ASSBs with long cycle life and high energy density.
Since the first report in 2011, layered transition-metal carbide/nitride (MXene) has been investigated as electrode materials for energy storage devices.1 MXene, which is represented with a general chemical formula M
n

+1X
n
T
x
(M = Ti, V, Nb, etc.; X = C and N; T = F, OH, O, etc.; n = 1–4), shows small volume change upon (de)lithiation with large specific capacities (~200 mAh g–1) at a low operation voltage (~1.0 V vs Li/Li+).2,3 The strain-free property of MXene is beneficial to improve the cycle life of all-solid-state batteries. In this presentation, we develop a high-capacity Ti2CT
x
MXene as an anode material for ASSBs. Li3PS4 glass is used as a solid electrolyte because its high ionic conductivity (~2×10–4 S cm–1) and high ductility.
Ti2CT
x
was synthesized by removing Al layers from Ti2AlC using a LiF/HCl etchant. Li3PS4 glass electrolyte was synthesized by mechanochemical milling. The Ti2CT
x
|Li3PS4 glass electrode delivers a specific capacity of 340 mAh g–1 at a specific current of 20 mA g–1 in a voltage range from –0.6 to 2.4 V vs. InLi. After the 80th cycle, 74% of the first discharge capacity is retained (239 mAh g–1) with a coulombic efficiency of 99.4% (Fig. 1). Electrochemical impedance spectroscopy indicates that a stable solid-solid interface forms between Ti2CTx and Li3PS4 glass, which is beneficial for the long cycle life.
Reference

X. Wang, S. Kajiyama, H. Iinuma, E. Hosono, S. Oro, I. Moriguchi, M. Okubo, A. Yamada, Nat. Commun. 6, 6544 (2015).

M. Okubo, A. Sugahara, S. Kajiyama, A. Atsuo, Acc. Chem. Rev. 51, 591–599 (2018).

K. Kawai, M. Fujita, R. Iizuka, A. Yamada, M. Okubo, 2D Mater. 10, 014012 (2023).

Figure 1