bluuebunny/crossref_metadata_2025 huggingface dataset:
A High Throughput Experimentation & Material Informatics Platform for the Discovery of Molten Salt Reactor Candidate Structural Materials
Authors: Goh Bonita , Wang Yafei , Nelaturu Phalgun , Moorehead Michael , Papailiopoulous Dimitris , Thoma Dan , Chaudhuri Santanu , Hattrick-Simpers Jason , Sridharan Kumar , Couet Adrien
Published: November 2022

ASME Sec(III) Div(5) code-certified structural alloys for Molten (halide) Salt Reactors (MSRs) such as 800H, SS316, and IN617 have significant Cr content. This makes them readily-degradable in molten halide salts due to the thermodynamic favorability of soluble chromium halide formation. It is therefore imperative to discover alloys with corrosion resistance that exceeds those of currently-certified alloys, which also possess the necessary high hardness and irradiation-resistance at reactor operating temperatures as a prerequisite for the licensing and deployment of MSRs.

The largely-unexplored quasi-infinite quarternary FeCrMnNi High Entropy Alloy space shows promise to yield desired alloys. We present a high-throughput (HTP) process demonstrating a turnaround time from fabrication to corrosion-testing and analysis of 1 week for 25 samples. 70 alloy samples of 1cm2 were each corrosion-tested on 0.3g salt droplets in isolated corrosion environments. The HTP platform includes the development of an in-situ high-temperature electrochemical sensor system capable of automating the analysis of dissolved corrosion product analytes in the salt.

The results of the 70 corrosion tests were used to train a Machine Learning model to predict corrosion performance metrics (eg. Elemental corrosion concentration into salt) based on an input vector parametrizing the physical properties (“descriptors”) of the alloys in the sample set. The model was tested on 20 additional samples and demonstrated conservative predictive capability as well as facilitated the reduction of input feature space from 62 dimensions to 4 dimensions with negligible loss in predictive accuracy.
Towards in-Situ Corrosion Measurements in Molten Fluoride Salt By Simultaneous X-Ray Absorption Spectroscopy and Electrochemistry
Authors: Khaykovich Boris , Fayfar Sean , Zheng Guiqiu , Sprouster David J. , Stavitski Eli
Published: November 2022

Effects of corrosion products on molten salt properties are a focus of many studies motivated by the needs of molten-salt nuclear reactors. We demonstrate in-situ measurements of corrosion products from NiCr (80%-20%) foil in molten FLiNaK. We used X-ray absorption spectroscopy (XAS) and a combination of XAS with electrochemical spectroscopy. Using XAS, we measured both the space and time distributions of Ni and Cr ions leaching from the foil and characterized their valence state and the local structure. We also correlated the XAS results with simultaneous electrochemical measurements. We also demonstrated a novel sample environment that we developed that enables simultaneous XAS and electrochemical measurements of molten fluoride salts. The next step of this program is to measure the corrosion on structural alloys such as stainless steel in molten FLiBe.
Multiphase Alloy Nuclear Waste Forms Developed for Pyrochemical U-10Mo Scrap Recovery Waste Streams
Authors: Gattu Vineeth Kumar , Ebert William L
Published: November 2022

The US High Performance Research Reactor (USHPRR) Conversion program is developing an Al-clad Zr-bonded U-10Mo nuclear fuel foil to enable the conversion of research reactors to high-assay low-enriched uranium (HALEU) alloy fuel. Fabrication scrap from the fuel manufacturing will be electrorefined to recover the HALEU, which will generate waste streams consisting of Zr, Mo, and residual U retained in the stainless steel anode basket used in the electrorefiner. Four alloys were formulated with different relative amounts of Zr, Mo, and 316L-SS to represent the expected range of waste compositions. Laboratory-scale ingots were made and metallurgically characterized to assess differences in the microstructures and distributions of the surrogate waste metals. Different amounts of the same dominant phases with similar compositions were formed in most materials: a γ-austenite based matrix, two ZrFe2 intermetallic phases that could host residual uranium, an FeCrMo sigma (σ) intermetallic phase, a chi (χ) phase, and a secondary austenite (γ2) phase. Electrochemical tests were conducted to compare the corrosion behaviors in acidic and alkaline brine solutions for a range of simulated environmental redox conditions. Corrosion of the Mo-rich γ and γ2 solid solutions and the σ and χ intermetallic phases occurred. The multiphase alloy waste form formulated with the lowest molybdenum and highest zirconium contents showed the highest corrosion resistance and has sufficient amounts of ZrFe2 to immobilize trace amounts of residual uranium in the waste stream. The alloy formulation strategy and testing approach will be presented with key results.

Work conducted at Argonne National Laboratory is operated for the U.S. Department of Energy, Office of Science under contact DE-AC02-06CH11357.
(Invited) Conducting Polymers As Dual Charge Conductors for Electrochemical Systems
Authors: Liu Gao
Published: November 2022

Electrically conductive polymers are a class of polymers, which can conduct electricity. Conductive polymers have found niche applications such as anti-statics. The electrochemical energy storage devices, especially lithium-ion rechargeable batteries, has grown significantly in the past two decades. Recently multifunctional conductive polymers have been designed as dual ion and electron transport materials, and synthesized through a thermal process. These class of dual charge conducting polymers play a significant role as electrode binders for Silicon (Si) and Tin (Sn) alloy based anode electrode. Si is an attractive candidate for lithium-ion batteries because it delivers 10 times greater theoretical (∼4200 mAh/g) specific capacity than that of a traditional graphite anode (∼370 mAh/g). However, the widespread application of silicon materials has remained a significant challenge because of the large volume change during lithium insertion and extraction processes, disrupting both the Si electrode surface and electrode mechanical integrity. This large volume change causes electrode failure, leading to loss of the electrical contact and drastic capacity fading. Nanosizing the Si and Sn based anode materials provides better performance, but poses significant challenges to manufacturing of the electrode, including particle aggregation, and difficulties in maintaining constant electrical contacts to the nanoparticles, and excessive surface area. Conductive polymer binders can play multiple functions for Si electrode, including improved adhesion and connectivity, lithium ion compensation, better ion and electric conductivity as well as surface and interface modification. Organic and polymer chemistry has provided almost infinity possibilities to modify the polymeric binders to include the desired functionalities. This presentation will discuss the specific molecular design principles and synthetic steps to realize the structures and functionalities of the binders, how these binders interact with different alloy materials, and the electrochemical performances of the electrodes based on these binders.
In Situ Visualization of the Hydrogen Distribution in an Fe Sheet Under Corrosion Conditions Using Polyaniline
Authors: Kakinuma Hiroshi , Ajito Saya , Hojo Tomohiko , Koyama Motomichi , Hiromoto Sachiko , Akiyama Eiji
Published: November 2022

High-strength steels are known to be susceptible to hydrogen embrittlement. Even small amounts of hydrogen which enter the high-strength steels under corrosion conditions could cause the hydrogen embrittlement. In order to elucidate the mechanism of hydrogen entry in corrosive environments, and to prevent the corrosion-induced hydrogen embrittlement, the simultaneous analysis of the corrosion behavior and the hydrogen entry is required. Some techniques, such as scanning Kelvin probe force microscope, have been reported for visualizing the hydrogen distribution in metals with a high spatial resolution. However, it is still challenging to visualize the hydrogen distribution of an observation area of several tens of millimeters with high spatial and temporal resolutions. In this study, we succeeded the visualization of the distribution of hydrogen entering a pure Fe sheet immersed in a NaCl aqueous solution using a conductive polymer.

A pure Fe sheet (99.5 %) was used as a specimen. The Fe sheet was electrically polished in a mixed solution of perchloric acid and acetic acid. The thickness of the Fe sheet was 0.4 mm after the polishing. In order to visualize the hydrogen distribution in the Fe sheet, a polyaniline (PANI) layer was formed on one side of the Fe sheet. It was reported that the PANI layer changes its color owing to the reaction with atomic state hydrogen in Fe sheets.1 To enhance the sensitivity of the PANI layer to hydrogen, a Ni interfacial layer was formed between the PANI layer and the Fe sheet. The PANI layer was formed on the Ni interfacial layer through electrolytic polymerization at a constant voltage of 1 V in a 0.5 M H2SO4-0.5 M aniline aqueous solution. On the other side (bare Fe side) of the Fe sheet, an electrode area of 1 cm × 1 cm was prepared using a resin. Only the bare Fe side was immersed in a 0.1 M NaCl aqueous solution. In addition to the open-circuit potential measurements, the corrosion behavior was observed in situ using a digital camera during the corrosion test. The PANI layer was exposed to air without contacting the NaCl solution. During the corrosion test, the color of the PANI layer was observed in situ using another digital camera. It was confirmed that the small amount of hydrogen entering the Fe sheet due to corrosion can be visualized using the PANI layer. The distribution of hydrogen that entered the Fe sheet was analyzed based on the color distribution of the PANI layer. The in situ simultaneous observation of the corrosion behavior and the hydrogen entry revealed that the hydrogen entry was promoted on the dissolved area of the Fe sheet in the NaCl solution.

Reference

H. Kakinuma, S. Ajito, T. Hojo, M. Koyama, E. Akiyama, Adv. Mater. Interfaces, 2101984 (2022).
Evolution of Surface Oxides of UNS S13800 during Cathodic Polarization in Chloride Solutions
Authors: Anderson Rachel M. , Hangarter Carlos M , Policastro Steven A
Published: November 2022

Solutions arising from atmospheric processes can have varying chloride concentrations, often higher than seawater as salt deposits accumulate in thin layer electrolytes. Understanding the corrosion behavior of stainless-steel fastener components is important to predicting its behavior in a galvanic couple with less noble materials. Here we have focused on the cathodic kinetics of UNS S13800 stainless steel over a range of chloride concentration electrolytes. The different oxides formed under these varying conditions are studied using surface analytical techniques. This information is then used to inform a model for fitting of the potentiodynamic polarization curves. The evolving composition of the surface oxide affects the polarization curve in the activation region of the oxygen reduction reaction. This additional cathodic current is accounted for in the model and the different reaction components of the polarization curve are extracted and analyzed.

Acknowledgments

The U.S. Naval Research Laboratory sponsored this project as part of their base program. The views and conclusions contained herein are those of the authors and should not be interpreted as necessarily representing the official policies or endorsements, either expressed or implied, of the Office of Naval Research, the U.S. Navy, the Department of Defense, or the U.S. government
(Invited) Garnet-Type Electrolytes for All-Solid-State Lithium Metal Batteries
Authors: Thangadurai Venkataraman , Palakkathodi Kammampata Sanoop , Yamada Hirotoshi
Published: November 2022

All solid-state Li batteries are foreseen as the future state of battery technology due to their safety, high energy density, and high potential window as compared to the present organic liquid electrolyte batteries. Li-ion conducting garnet-type electrolytes have received considerable research interests due to their compatibility with Li metal anode, good ionic conductivity (10-3 S/cm) and wide electrochemical window (~ 6V vs. Li).1 Garnet-type Li6.5La3-xAxZr1.5-xTax+0.5O12 (A = Ca, Sr, Ba; x = 0.1, 0.5) solid electrolytes were prepared by conventional solid-state synthesis and spark plasma synthesis (SPS).2-4 The formation of the cubic garnet-type structure was confirmed by powder X-ray diffraction (PXRD). Microstructure of the solid electrolytes were analysed by scanning electron microscopy (SEM) and cross-sectional analyses showed that the SPS processed samples are highly dense compared to the same compositions prepared by conventional solid-state route. The AC electrochemical impedance spectroscopy (EIS) was used to measure the impedance of solid electrolytes and found that all samples exhibit bulk conductivity in the order of 10-4 S/cm at room temperature. SPS processed samples showed an excellent Li-ion charge transfer resistance and the highest critical current density compared to the samples prepared by conventional solid-state synthesis. X-ray photoelectron spectroscopy (XPS) analyses were conducted on SPS-processed samples to quantify the impurity layers on garnet surface. Electrochemical performance of a hybrid cell consisting of liquid Li-ion electrolytes and garnet electrolyte will be discussed.

References

Wang, K. Fu, S. Palakkathodi Kammampata, D. W. McOwen, A. Junio Samson, L. Zhang, G. T. Hitz, A. M. Nolan, E. D. Wachsman, Y. Mo, V. Thangadurai and L. Hu, Chem. Rev., 2020, 120, 4257–4300.

Palakkathodi Kammampata, R. H. Basappa, T. Ito, H. Yamada and V. Thangadurai, ACS Appl. Energy Mater., 2019, 2, 1765–1773.

Palakkathodi Kammampata, H. Yamada, T. Ito, R. Paul and V. Thangadurai, J. Mater. Chem. A, 2020, 8, 2581–2590.

Yamada, T. Ito, S. P. Kammampata and V. Thangadurai, ACS Appl. Mater. Interfaces, 2020, 12, 36119–36127.
(Invited) Flexible and Safe Zinc Alkaline Solid-State Rechargeable Battery for Wearable Applications
Authors: Madan Deepa , Poosapati Aswani , Ambade Rohan
Published: November 2022

Wearable electronics are one of the most rapidly growing industries, due to their extended use in everyday applications resulting in an increased demand for portable energy storage devices. Despite immense success in commercialization of Lithium-ion batteries (LIBs), conventional LIBs suffer from issues of cost and safety. The expanding need for cheaper, and safer energy storage devices led explorations towards alternatives. After careful considerations, Zinc (Zn)-Manganese dioxide (MnO2) based alkaline system was chosen to be investigated in this work due to its low cost, inherent safety, and high theoretical energy density. However, challenges associated with making the aforementioned system rechargeable and highly performing still remains. The work in this study is directed towards enhancing the overall performance of the Zn-MnO2 alkaline battery in addition to making it suitable for flexible and wearable applications. A highly ionically conducting polymer electrolyte ({5}CP) with excellent physical and electrochemical stability primarily comprising biopolymer chitosan is prepared by using a time and energy-efficient technique. Incorporation of this polymer electrolyte with Zn anode and MnO2 cathode enabled the successful preparation of a physically flexible cell. To obtain high cyclability and performance of the system; issues of inactive phase formations (MnxOy, ZnMnxOy), low active material availability, pronounced shape changes at the anode surface, and zincate ion transfer towards cathode were overcome by enhancing the electrochemically active layers in the system. The assembled cell comprising the enhanced fabricated layers; (i.e. a Zinc/Stainless steel mesh composite anode, a hierarchical binder-free bismuth and copper additives based MnO2 cathode, and a chitosan-based polymer electrolyte with calcium hydroxide additive) indicated excellent rate capabilities (486 mAh/g @ 0.1 A/g, 78% of the theoretical 2-electron capacity on MnO2), long cycling stabilities (70% retention over 1000 cycles), and good energy densities (155 – 400 Wh/kg @ 0.1 – 1 A/g). Moreover, a number of destructive tests such as being bent, hammered, pressurized, and punctured were conducted on the pouch cell fabricated using the above-mentioned layers to analyze the cells’ safety, reliability, and robustness. Results indicated not much deterioration in capacities. Additionally, when the cell was bent and tested for long performance; a stable discharge capacity (270 mAh/g @ 1 A/g) was obtained after 250 cycles, thus attesting to excellent cycling stability. The successful working of the fabricated cell was validated by lighting up an LED. The successful findings presented in this study can chart new pathways to the development of safe, flexible, cost-effective, and more environmentally responsible alternative energy storage sources for wearables.
Exploring the Safety Aspects of Redox Flow Batteries
Authors: Juarez-Robles Daniel , Rauhala Taina , Jeevarajan Judith
Published: November 2022

Redox flow batteries are energy storage systems consisting of liquid electrolytes containing one or more electroactive species. Electrolytes flow through the electrochemical cell where chemical energy is converted into electricity. The energy stored by the redox flow batteries depends on the volume of electrolytes in the tanks and the size of the electrochemical battery. If the electrolytes deteriorate, they can be replaced, and the battery's capacity will get restored.

Factors and components affecting performance have been extensively studied but not the response to off-nominal tests. In this work, performance (cycle life) and safety tests (overcharge, overdischarge and short circuit) are carried out on two conventional redox battery systems, Vanadium (V) and Zinc-Bromine (Zn-Br). The vanadium-based flow battery is of a table-top lab-scale size, whereas, the Zn-Br batteries are residential-scale systems.
(Digital Presentation) Multimodal Encapsulation of p-SnOx to Engineer the Carrier Density for Thin Film Transistor Applications
Authors: Lee Dong Hun , Zhang Yuxuan , No Kwangsoo , Song Han Wook , Lee Sunghwan
Published: November 2022

It has been challenging to synthesize p-type SnOx (1≤x<2) and engineer the electrical properties such as carrier density and mobility due to the narrow processing window and the localized oxygen 2p orbitals near the valence band.

We recently reported on the processing of p-type SnOx and an oxide-based p-n heterostructures, demonstrating high on/off rectification ratio (>103), small turn-on voltage (<0.5 V), and low saturation current (~1×10-10 A)1. In order to further understand the p-type oxide and engineer the properties for various electronic device applications, it is important to identify (or establish) the dominating doping and transport mechanisms. The low dopability in p-type SnOx, of which the causation is also closely related to the narrow processing window, needs to be mitigated so that the electrical properties of the material are to be adequately engineered 2, 3.

Herein, we report on the multifunctional encapsulation of p-SnOx to limit the surface adsorption of oxygen and selectively permeate hydrogen into the p-SnOx channel for thin film transistor (TFT) applications. Time-of-flight secondary ion mass spectrometry measurements identified that ultra-thin SiO2 as a multifunctional encapsulation layer effectively suppressed the oxygen adsorption on the back channel surface of p-SnOx and augmented hydrogen density across the entire thickness of the channel. Encapsulated p-SnOx-based TFTs demonstrated much-enhanced channel conductance modulation in response to the gate bias applied, featuring higher on-state current and lower off-state current. The relevance between the TFT performance and the effects of oxygen suppression and hydrogen permeation is discussed in regard to the intrinsic and extrinsic doping mechanisms. These results are supported by density-functional-theory calculations.

Acknowledgement

This work was supported by the U.S. National Science Foundation (NSF) Award No. ECCS-1931088. S.L. and H.W.S. acknowledge the support from the Improvement of Measurement Standards and Technology for Mechanical Metrology (Grant No. 20011028) by KRISS. K.N. was supported by Basic Science Research Program (NRF-2021R11A1A01051246) through the NRF Korea funded by the Ministry of Education.

References

Lee, D. H.; Park, H.; Clevenger, M.; Kim, H.; Kim, C. S.; Liu, M.; Kim, G.; Song, H. W.; No, K.; Kim, S. Y.; Ko, D.-K.; Lucietto, A.; Park, H.; Lee, S., High-Performance Oxide-Based p–n Heterojunctions Integrating p-SnOx and n-InGaZnO. ACS Applied Materials & Interfaces
2021,
13 (46), 55676-55686.

Hautier, G.; Miglio, A.; Ceder, G.; Rignanese, G.-M.; Gonze, X., Identification and design principles of low hole effective mass p-type transparent conducting oxides. Nat Commun
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Yim, K.; Youn, Y.; Lee, M.; Yoo, D.; Lee, J.; Cho, S. H.; Han, S., Computational discovery of p-type transparent oxide semiconductors using hydrogen descriptor. npj Computational Materials
2018,
4 (1), 17.

Figure 1
Enhancing Aqueous Zinc Metal Anode Reversibility with the Nucleation Sites Given by Oxidized Black Phosphoruspresentation
Authors: Baek Sangha , Park Jae Min , Kang Taehun , Park Ho Seok
Published: November 2022

Electric vehicles and renewable energy have gain lots of interests as a trial to protect environment and to prepare the depletion of fossil fuels. However, currently widely used lithium-ion batteries have disadvantages such as safety issue due to the fire hazard from organic electrolytes and non-uniform distribution of lithium reserves. Accordingly, aqueous zinc ion battery is attracting attention as an alternative because of the use of zinc, which has about 17 times more reserves than lithium, and the use of aqueous electrolyte, which has a low risk of fire. To achieve the high-performance aqueous zinc ion battery, zinc metal has been studied a lot due to its high theoretical capacity (820 mA/g). However, there are several huddles to use the zinc metal as an anode. Low reversibility due to the dendrite formation, exhaustion of electrolyte from the hydrogen evolution reaction, and low energy efficiency coming from high overpotential during charge and discharge steps are them. In this study, we tried to overcome these shortcomings by using black phosphorus. Black phosphorus with a layered structure can make phosphorene, a two-dimensional structure like graphene, through exfoliation. Such phosphorene has the advantage of being able to increase the effect of functionalization because the surface occupies a large proportion of the total. Specifically, after oxidizing exfoliated black phosphorus, we could chemically attach it to the zinc surface, a water-stable two-dimensional coating layer was formed. It could drive a uniform and facile deposit of zinc. Computational and experimental methods were used to understand this role of oxidized black phosphorus.
Threshold Switching in CdTe Photovoltaics
Authors: Devkota Suman , Nyako Kwame Asiedu Owusu , Kuzior Brendan , Karpov Victor , . Georgiev Daniel G , Li Frank , Cortes Pedro , Borra Vamsi
Published: November 2022

With the ubiquitous acceptance of PVs, the number of devices manufactured annually is following an exponential trend. Yet, the manufacturing process of important brands of thin-film solar cells involves a tedious and expensive step of laser scribing. The time-consuming and technologically involved laser scribing method remains widely used to contact the device electrodes.

This work examines an alternative method (threshold switching phenomenon) to create an enduring conductive path in cadmium telluride (CdTe) PV, which eliminates the pitfalls in conventional scribing technology. The samples undergone threshold switching show a promising sign of the conductive path compared to the control samples. This method could potentially lead to the manufacturing technology, which would save time, money, and raw materials in addition to the added reliability and efficiency.
High-Performance Perovskite Solar Cells Fabricated By Solvent Volatilization Method
Authors: Zhang Qiqi , Dai Qilin
Published: November 2022

Perovskite solar cells have attracted significant research efforts due to their remarkable performance, but most of them are prepared by the anti-solvent method. It’s not suitable for repeatability and large-scale production. We develop a perovskite film fabrication technique based on MAFAPbI3Cl precursor films, through annealing arrived recrystallization, forming high-quality perovskite films. The photovoltaic properties of the perovskite films fabricated with different experimental parameters are studied. The films prepared by our method show high reproducibility, facile operation, and significant potential in large-scale production. We use excess amount formanidinium iodide (FAI) to adjust the amount of methylammonium chloride (MACl) to optimize MAFAPbI3Cl precursor film. The experimental parameters include FAI amount and MACl amount are utilized to form high-quality perovskite films. Film structural and optical properties are studied by X-ray diffraction (XRD), UV-vis absorption spectra, photoluminescence (PL), time-resolved photoluminescence (TRPL) techniques. The best solar cell PCE reaches 20.64 % with the average PCE of 20%. These perovskite solar cells also exhibit excellent high stability and repeatability. We believe this work develops a way for the commercialization of perovskite solar cells.
(Digital Presentation) The Electrode’s Inhomogeneous Microstructure Effect on Battery Performance
Authors: Odetallah Mariam , Singh Vikram , Kuss Sabine , Kuss Christian
Published: November 2022

Currently, rechargeable batteries are used in everyday life applications, such as in mobiles, cameras, laptops, and cars. Accordingly, the demand for rechargeable batteries, in particular Lithium-ion batteries, is increasing. Their electrodes consist of at least four different materials: active material, a conductive additive, polymer binder, and current collector. The battery performance in terms of cycling performance, energy density, mechanical integrity, and ionic and electronic mobility depends on these materials.1

The casting procedure, the multiscale packing during the evaporation process after casting, the accumulation of the conductive additive, the adhesive failure during the charging and discharging process, and the natural irregular shape of the electrode materials produce an inhomogeneous electrode microstructure. 2 This inhomogeneity causes current density variation and a non-uniform Lithium ion concentration leading to damage to the battery structure, reducing the capacity, and degrading the battery. 2

The electrode microstructure and its effect on the battery performance have great importance. As such, several techniques have been developed to investigate electrode microstructure. Each technique gives specific information. Here, we will combine scanning electron microscopy (SEM), scanning electrochemical microscopy (SECM), and battery cycling to study the effect of microstructure on the battery performance.

SECM is a high resolution probe technique that scans the electrode surface using an ultra-microelectrode. Thus it can measure the electrode`s local conductivity.3
,
4 Therefore, we can quantify the inhomogeneous microstructure distribution. Thus, by combining these results with SEM and cycling test results we will be able to find the correlation between the battery performance and the distribution of the microstructure.

References:

Stein M, Chen CF, Robles DJ, Rhodes C, Mukherjee PP. Non-aqueous electrode processing and construction of lithium-ion coin cells. J Vis Exp. 2016;2016(108):1-10. doi:10.3791/53490

Xiong R, Zhang T, Huang T, Li M, Zhang Y, Zhou H. Improvement of electrochemical homogeneity for lithium-ion batteries enabled by a conjoined-electrode structure. Appl Energy. 2020;270(May):115109. doi:10.1016/j.apenergy.2020.115109

Ventosa E, Schuhmann W. Scanning electrochemical microscopy of Li-ion batteries. Phys Chem Chem Phys. 2015;17(43):28441-28450. doi:10.1039/c5cp02268a

Polcari D, Dauphin-Ducharme P, Mauzeroll J. Scanning Electrochemical Microscopy: A Comprehensive Review of Experimental Parameters from 1989 to 2015. Chem Rev. 2016;116(22):13234-13278. doi:10.1021/acs.chemrev.6b00067
(Invited) Advancing 3D Packaging for Heterogenous Systems Integration
Authors: Elsherbini Adel
Published: November 2022

Next generation computing architectures including those for machine learning and AI (Artificial Intelligence) have increasing demands on bandwidth, memory capacity and energy efficiency. All of which can be improved through the increased integration density offered by advanced packaging technologies. In this talk, we will provide an overview of the different 3D integration technologies and cover their scaling and application considerations. These include technologies for direct die to die connections such as advanced solder interconnects at 20 and 10 µm pitch and hybrid bonding or Foveros Direct to support increased interconnect density to below 10 µm pitch or more than 10,000 connections/mm2. The increased interconnect density can dramatically improve the bandwidth capability and energy efficiency. We will also cover some of the considerations for 3D die stacking such as thermal hot spots and power delivery constraints and how these can be addressed through design and packaging technology combinations. Finally, we will discuss some future directions to support continued performance improvement.
(Invited) How the Semiconductor Research Corporation (SRC) Is Expanding Robust Advanced Packaging with the US and like-Minded Allies
Authors: Oakley John Richard
Published: November 2022

As investments in technology are made it will be important to consider what technologies are invested in. Advanced Packaging will be the key enabler of the next microelectronic revolution, as it allows increasing device density and functionality per footprint while realizing a broad spectrum of new products through heterogeneous integration. In fact, advanced packaging is becoming equivalent of the transistor of the Moore’s Law and ITRS era. However, the US lacks the necessary advanced packaging ecosystem: the US has not been a cost-effective location to develop a robust advanced packaging sector. The Semiconductor Research Corporation (SRC) is leading efforts in expanding robust advanced packaging with the US and like-minded allies.

SRC has also served as a beacon for the community and has been relied on to bring similar but different interests together to achieve consensus on direction setting for the industry. Through a series of five workshops, 50+ presentations, and hundreds of international experts from industry, government, and academia SRC published the 2030 Decadal Plan For Semiconductors in January 2021. By soliciting participation from experts in all parts of the semiconductor ecosystem, the Decadal Plan serves to define the technical needs to achieve strategic goals by 2030, informing the community of ‘what’ needs to be done and not the ‘how’.

Figure 1
(Invited) Assessing Reliability of Materials for Electronic Interconnects
Authors: Keller Robert
Published: November 2022

Reliability of materials refers to how well an engineered material performs its intended function over a targeted design lifetime. Quantitatively, reliability is defined as (1 − probability of failure). Because a material’s physical properties are determined by its atomic makeup, reliable material function fundamentally depends on the stability of atomic structure as that material sees continued exposure to operational conditions. From the interconnect perspective, the primary functions include routing signal and power within and between devices or other subcomponents. Any disruptions to the atomic arrangement of materials used as interconnects therefore change the ability of those interconnects to perform those functions. An important aspect of designing these structures for high reliability therefore involves measuring and understanding how operational stressors can lead to the formation and evolution of defects in atomic structure over time. This type of knowledge can then at a minimum be used to predict when those effects unacceptably compromise interconnect functionality. Better yet, it can be used to improve material processing to slow or even eliminate damage. While interconnect technology has undergone significant changes and improvements over the years due to new materials, material systems, dimensions, and architectures, the fundamental factors that remain a chronic concern for reliability of interconnects used in BEOL and packaging are a combination of temperature, electric current, and mechanical strain. Our work addresses methods to test, detect, and ultimately control material defects, reliability, and failure. In this contribution, I will summarize some of our work to measure damage due to thermal fatigue and electromigration in several materials, including aluminum, copper, carbon nanotubes, and 2D molybdenum disulfide. I will also summarize some of our recent developments in material characterization, which we believe can play an important role in assessing material reliability for the semiconductor industry.
Cold Sintering–a New Approach to Reprocess Composite Electrolytes in All-Solid-State Lithium-Ion Battery
Authors: Lan Yi-Chen , Gomez Enrique Daniel
Published: November 2022

As all-solid-state lithium-ion batteries (ASSBs) start to dominate the electronic market, studies regarding to recycling spent batteries remain limited and uncomprehensive. The primary factor causing the failure of batteries is the loss of structural integrity in solid-state electrolytes (SSEs) with limited degradation in the active properties. A promising reprocessing strategy is to repair the fragmented structure. Herein, solid-state composite electrolytes, Li7La3Zr2O12 with polypropylene carbonate (PPC) and lithium perchlorate (LLZO–PPC–LiClO4), are reprocessed by cold sintering process. The low sintering temperature allows co-sintering ceramics with polymers and salts, thereby enabling densifying composite structures. Reprocessed LLZO–PPC–LiClO4 show densified microstructures with ionic conductivities above 10−4 Scm−1 at room temperature and good long-term stability at 0.1 mA h cm−2 over 2000 hours. The cold sintered full-cell, Li4Ti5O12/ reprocessed LLZO–PPC–LiClO4/LiFePO4, exhibits impressive electrochemical performance.
Low Temperature Semiconductor Device Processing
Authors: Lill Thorsten , Fischer Andreas , Berry Ivan , Shen Meihua
Published: November 2022

In the manufacturing of integrated circuits, etching and deposition processes with and without plasma are widely used. Except for physical processes such as Physical Vapor Deposition and Ion Beam Etching, these processes leverage the adsorption of reactive neutrals to enable chemical reactions at the wafer surface.

In this paper, we will investigate the fundamentals and applicability of low temperatures to stimulate physisorption of neutrals. Among the points of interest for this approach are the use of less reactive gases, higher fluxes to the surface, new transport mechanisms into high aspect ratio features, and 3D effects thanks to condensation in small features.

We will discuss temperature and pressure ranges for relevant material and pre-cursor gas combinations and means to initiate the deposition and etching reactions. An overview of experimental results from our research and the literature will be presented.
Membrane Transport and Performance in the All-Aqueous Copper Thermally Regenerative Battery
Authors: Cross Nicholas R. , Springer Renaldo E , Rau Matthew J. , Lvov Seguei N , Logan Bruce E. , Gorski Christopher A. , Hall Derek M.
Published: November 2022

Redox flow batteries are emerging as a promising method to provide grid-scale power and long-duration energy storage safely and economically. The thermally regenerative ammonia battery (TRAB) is a new redox flow battery category that can be recharged using low-grade waste heat rather than electric energy, adding further flexibility to the applicability of flow battery systems. Recently, a new TRAB with all-aqueous electroactive species (referred to as the Cuaq-TRAB), as opposed to deposition-dissolution reactions, was found to have superior energy and power densities relative to competing TRABs. The use of bromide and ammonia stabilizes for both Cu(I) and Cu(II) oxidation states, while also creating a cell potential of up to 1.0 V. The potential can be recovered by thermally separating ammonia from the electrolyte and adding it back to alternate electrolyte chambers in successive cycles. Potential improvements in overall cell performance are possible by reducing ohmic losses associated with membrane selection. However, the ideal membrane for the Cuaq-TRAB is not obvious and raises interesting transport questions relative to the dominant redox-active copper species being negatively charged in the catholyte but positively charged in the anolyte. Furthermore, membrane crossover of ammonia, a small, uncharged molecule, was previously shown to be a primary source of parasitic losses for TRABs. Therefore, we investigated how different membrane types (cation, anion, and non-selective) affected ion transport and TRAB performance. A batch symmetry cell was used to determine membrane conductivity in the Cuaq-TRAB environment and membrane diffusion coefficients of each species in the electrolytes. Flow cell experiments were also conducted to find peak power, energy density, average power during discharge, and capacity fade over successive electric charge/discharge cycles. Tradeoffs between membrane conductivity and permeability observed in the symmetry cell are manifested in flow cell results as either high peak and average power or high energy density and low capacity fade. These results expand on potential methods for controlling transport in redox flow batteries and demonstrate the potential for non-selective membranes for electrochemical energy technologies.
(Keynote) N-Heterocyclic Carbene-coated Gold Nanoparticles and Luminescent Quantum Dots
Authors: Mattoussi Hedi , Du Liang , Nosratabad Neda Arabzadeh , Jin Zhicheng
Published: November 2022

N-heterocyclic carbenes (NHCs) have generated much interest for use as versatile metal-coordinating groups, since they were first synthesized by Arduengo and coworkers in 1991. NHC molecules can be considered as L-type ligands, because they share their non-bonding electron pairs with the σ-accepting orbital of transition metals, and this endows them with strong coordination interactions. NHC-appended molecules have recently been actively exploited as potentially effective ligands for the surface passivation of various colloidal nanomaterials.

We investigate the coordination interactions between a few representative colloidal nanocrystals, including gold nanoparticles (AuNPs) and luminescent quantum dots (QDs), and a NHC-based polymer ligand. The latter presents multiple NHC groups and several short poly (ethylene glycol) (PEG) chains as solubilizing blocks. We find that our NHC-decorated ligands rapidly coordinate onto both sets of nanocrystals, which we attribute to their soft Lewis base nature. These ideally match the soft Lewis acid character of transition metal colloid surfaces, promoting strong coordination bonding through soft‐soft interaction. We combine NMR spectroscopy, fluorescence spectroscopy, high-resolution transmission electron microscopy supplemented with dynamic light scattering to characterize the nature of the binding interactions. Furthermore, the long-term stability of the NHC-stabilized nanocolloids have been tested after phase transfer to water, a highly challenging chemical venue for such groups, due to the moisture sensitive nature of NHC molecules. Data show that our NHC-polymer-stabilized AuNPs and QDs exhibit long-term colloidal stability in buffer media while preserving their optical and fluorescing properties, with no sign of degradation or aggregation build up for at least one year of storage. We will discuss the ligand design and synthesis, characterization of the polymer-stabilized nanocrystals under various conditions, with a particular focus on the beneficial effects of ligand multi-coordination interactions onto the nanocolloid surfaces.
(Invited, Digital Presentation) Ultrafast Spectroscopy of Inorganic Perovskite Nanocrystals and Their Assemblies: Uncovering the Multiple Exciton Generation Rate and Band-Formation
Authors: Timmerman Dolf , Tang Ying Ying , Schall Peter , Fujiwara Yasufumi
Published: November 2022

Inorganic perovskite nanocrystals (NCs) display attractive structural and optical properties, and have perspective in a wide range of optoelectronic applications. One interesting feature is their relatively slow hot carrier cooling rate, which allows to follow carrier dynamics in great detail with ultrafast spectroscopic techniques.

In this talk, we present studies of the ultrafast carrier dynamics of perovskite NCs and assembled structures. Typically, when the excitation photon energy is increased, and thus the excess energy of the created carriers, the cooling time of the carriers towards the bandedge increases along. However, for CsPbI3 NCs, when the photon energy exceeds a certain threshold energy the cooling time starts to decrease, indicating that a competing relaxation pathway opens up which funnels carriers towards the bandedge. This threshold energy indicates the onset of a carrier multiplication process, in which absorption of a single photon leads to the creation of multiple electron-hole pairs. This process can also be inferred by following the carrier concentration, which shows a delayed build-up following the excitation pulse. The carrier dynamics in this system can be modeled within a framework of two competing cooling mechanisms. With the experimentally determined carrier cooling rate and threshold energy it is possible to extract the time-constant associated with the carrier multiplication process.

Experiments on highly ordered CsPbBr3 NCs, so-called supercrystals, revealed how the photophysics are altered due to the inter-NC coupling as compared to the individual NCs. Next to a red-shift of the absorption and photoluminescence peak, the supercrystals show signatures of band-like states. The observation of a reduced Stokes-shift, decreased biexciton binding energy and increased carrier cooling rates, support the formation of delocalized states resulting from the coupling between individual NCs. These results open perspectives for assembled NCs for application in optoelectronic devices, with design opportunities exceeding the level of nanocrystal and bulk material.
(Invited) In Situ TEM Studies of Colloidal Inorganic Nanocrystals for Energy Applications
Authors: Reifsnyder Hickey Danielle
Published: November 2022

Sustainable technologies will be essential for meeting future energy demands. Therefore, it is critical to be exploring the fundamental science of materials for photovoltaics and catalysis. For these applications, nanomaterials hold great promise due to their unique, size-dependent properties, tunability, and solution processability. Additionally, nanomaterials offer an effective testbed to understand structural transformations in bulk materials, and to take advantage of effects related to having a high surface area to volume ratio.

Transmission electron microscopy (TEM) allows a unique window into the atomic structures of nanomaterials by enabling high-resolution imaging, electron diffraction, and compositional analysis. Specifically, this work explores local structural and compositional transformations by examining how colloidal nanocrystals transform under in situ conditions during imaging. Focusing on halide perovskite nanocrystals for photovoltaic applications and metal nanocrystals for catalytic applications, the roles of size, shape, and composition will be explored, as well as the impact of atomic defects.

The degradation of halide perovskites is a major issue facing the field and can be mitigated by an in-depth understanding of the structural changes that occur during degradation processes. For instance, the relative stability of different compositions and dissimilar geometries can provide insights into which factors could improve the longevity of photovoltaic devices. Similarly, metallic nanocrystals for heterogeneous catalysis rely on reactive surfaces, which can be identified, examined, and transformed during in situ TEM experiments. This presentation will describe progress toward understanding transformation mechanisms in these two classes of nanocrystals, and it will provide comparative insights across the systems.
(Invited, Digital Presentation) Photovoltaic Applications Using Energy Transfer Characteristics from Quantum Dots
Authors: Fukata Naoki , Jevasuwan Wipakorn
Published: November 2022

Silicon-related materials are most commonly used in solar cells and become now an invaluable material. However, a reported maximum energy conversion efficiency of Si solar cell is close to reaching its theoretical limits. To further improve the cell performance and create new functions, it will become increasingly important to functionalize Si materials using nanostructures. One- and zero-dimensional Si nanostructures called Si nanowires (SiNWs) and Si quantum dots (Si QDs) are increasingly being used as new solar cell materials. Our group has shown that the conversion efficiency of solar cells can be increased by the non-radiation energy transfer (NRET) from Si QDs [1]. Recently, research has been developed on compound semiconductor QDs and perovskite QDs, and the conversion efficiency has been successfully increased [3-7].

n-type SiNW arrays were fabricated by electroless etching and Bosch & nanoimprint lithography followed by CVD process. The CVD process was performed to form p-type Si layer for pn homojunction. Hybrid heterojunction cells of PEDOT:PSS and n-SiNWs were also fabricated. Passivation by ozone and hydrogen were applied to improve the solar cell properties [2]. After the cell fabrications, the solar cells were coated with Si QDs, CdZnS/ZnS QDs, CdZnSe/ZnS QDs and perovskite QDs. The fabrication methods and conditions of QDs have been reported elsewhere [1-7]

Energy transfer effects such as NRET are new ways of increasing solar cell efficiency. To effectively use the NRET effect, the surface of Si QDs should be fully passivated by ligand molecules. The NRET process is a highly distance-dependent phenomenon, and its dependence on the length of the passivation ligands clearly showed this. NRET efficiency was increased by shortening the ligand length from 1-octadecene to 1-octene, resulting in higher JSC, ultimately providing higher energy conversion efficiency. The efficiency was increased about 1-2 % by adding SiQDs. We also observed the same effect for CdZnS/ZnS QDs, CdZnSe/ZnS QDs and perovskite CsPbCl3 QDs. In these cases, in addition to the NRET effect, the radiative energy transfer (RET) effect also contributes to the increase in conversion efficiency.

References: [1] M. Dutta et al, ACS Nano 2015, 9, 6891 (2015). [2] M. Dutta et al, Nano Energy 2015, 11, 219. [3] N. Fukata et al., Small 2017, 13, 1701713. [4] J. Chen et al., Nano Energy 2019, 56, 604. [5] M. F. Abdelbar et al., Nano Energy 2020, 77, 105163. [6] M. Abdelhameed et al., Nano Energy 2020, 82, 105728. [7] M. F. Abdelbar et al., Nano Energy 2021, 89, 106470.