bluuebunny/crossref_metadata_2025 huggingface dataset:
Enhanced Property Tunability of Doubly Doped Semiconductor Nanomaterials Using the Cluster Seed Method
Authors: Pálmai Marcell , Tomczak Kyle , Snee Preston
Published: November 2022

Semiconductor Quantum Dots (QDs) have great potential in applications for renewable energy generation due to their size-tunable redox potentials. They may be prepared with different morphologies and coated to create complex heterostructures. Doping of semiconductor nanomaterials is another mechanism to realize property tunability, and doped QDs are playing an increasing role in green energy generation applications. In 2013 our group reported a method to create a batch of doped quantum dots where each particle was embedded with the same number of guest ions, thus circumventing Poisson statistics. This was accomplished by nucleating the QD around an organometallic seed cluster that contains guest ions. As a result, each QD has the same number of dopants, which eliminates problems due to inhomogeneity of the guest ion stoichiometry. These materials were studied using time-resolved X-ray absorption spectroscopy, which allows us to characterize the electronic and coordination structure in both the ground and excited states.

Current research reveals the potential to doubly dope semiconductors using cluster seeding, and that the originating organometallic structure may be represented in the final material product. To this end, ZnCdSe nanowires were prepared in the presence of (MnTe)4 cluster seeds. The results reveal that Mn(2+) has been successfully incorporated into the host matrix, while temperature dependent optical measurements suggest significantly enhanced semiconductor exciton-magnetic dopant interactions in materials prepared by cluster seeding compared to doped control samples. This could be due to ferromagnetic Mn-Mn interactions in the host resulting from enhanced exchange coupling mediated by highly spin-orbit coupled tellurium bridging. Consequently, cluster seeding may be used to "dope the dopants", affording a heretofore unrealized method for developing designer materials with enhanced electronic and optical properties.

Figure 1
(Invited, Digital Presentation) Physical Properties of Silicon-Germanium Nanostructures: Theory and Simulations
Authors: Amato Michele
Published: November 2022

Silicon germanium nanostructures (SiGe NSs) have acquired today a prominent role in several cutting-edge research topics in nanoscience, thanks to the most recent advances in synthesis, processing and characterization [1-4]. The physical properties of such nanosystems are strictly related not solely to the size of the system (as in pure Si and Ge NSs), but also to the relative composition of Si and Ge atoms as well as to the geometry of Si/Ge interface. The investigation of these materials with experimental techniques is, however, complicated by several factors not always well controlled which can hide the right comprehension of the fundamental properties. In this context first principles theoretical modeling is extraordinarily important as it can complement or augment experimental observations.

Here, I will present an overview of the ab initio computational modeling of various types of SiGe nanosystems (nanowires [5], nanodots [6] and slabs [7-8]). I will outline how by bringing together two similar elements –Si and Ge, neighbors in the periodic table–, a broad variety of new chemical and physical properties emerge, stimulating both fundamental and application-driven research in nanoscience. Indeed, I will show that substituting some of the atoms of a pure Si NS with Ge in configurations of distinct compositions and dimensionalities, can strongly affect some fundamental properties such as band gap, band offsets, work function and impurity doping levels.

Bibliography

[1] M. Amato, M. Palummo, R. Rurali, S. Ossicini, Chem. Rev. 114, 1371 (2014)

[2] I. Berbezier, A. Ronda, Surf. Sci. Rep., 64, 47 (2009)

[3] J.-N Aqua, I. Berbezier, L. Favre, T. Frisch, A. Ronda, Phys. Rep., 522, 52 (2013)

[4] D. J. Paul, Semicond. Sci. Technol. 19, R75–R108 (2004)

[5] M. Amato, S. Ossicini and R. Rurali, Nano Lett. 11, 2, 594-598 (2011)

[6] I. Marri, M. Amato, S. Ossicini, S. Grillo, O. Pulci, Interplay of quantum confinement and strain effects in type I to type II transition in Ge/Si core-shell nanocrystals (submitted, 2022)

[7] I. Marri, M. Amato, M. Bertocchi, A. Ferretti, D. Varsano, S. Ossicini, Phys. Chem. Chem. Phys. 22, 25593-25605 (2020)

[8] S. Pouch, M. Amato, M. Bertocchi, S. Ossicini, N. Chevalier, T. Mélin, J.M. Hartmann, O. Renault, V. Delaye, D. Mariolle, L. Borowik, J. Phys. Chem. C 119, 26776-26782 (2015)
(Keynote) Rational Design of Quantum Dot/Mediator Interfaces for Triplet Energy Transfer and Photon Upconversion
Authors: Lian Tianquan
Published: November 2022

Photon upconversion, where two or more low energy photons are converted into one high energy photon, shows great potential in bioimaging, catalysis and solar energy conversion. Photon upconversion has traditionally been realized with lanthanide-doped nanoparticles, or organic dye sensitized triplet-triplet annihilation (TTA) based upconversion platforms. In recent years, QD sensitized triplet-triplet annihilation based upconversion systems have achieved impressive upconversion quantum efficiency and demonstrated many unique advantages, including high photostability, large extinction coefficient, high spectral coverage and tunability, and low singlet-triplet energy gap. In this talk, we discuss our recent work in developing and understanding QD/mediator interface for efficient QD-sensitized photon upconversion. We summarize the main results of time-resolved spectroscopic studies of various factors affecting the rate of triplet energy transfer (TET) from the QD to the surface attached mediator (TET1) and from the mediator to the emitter in solution (TET2). To identify the key design rules, we compare three PbS sensitized upconversion systems using three mediator molecules with the same tetracene triplet acceptor at different distances from the QD. Our results show that the mediator triplet state is mostly formed by direct TET from quantum dot. With increasing distance between the mediator and PbS QD, the efficiency of the TET1 from the QD to the mediator decreases due to a decrease in the rate of this triplet energy transfer step, while the efficiency of the TET2 from the mediator to emitter increases due to a reduction in the QD induced mediator triplet state decay (via the external heavy atom effect). The rate constant of TET2 is three orders of magnitude slower than the diffusion limited value. We show that the effect of QD/mediator on the total unconversion efficiency measured under CW illumination conditions can be well accounted for by the independently determined efficiencies of TET1 and TET2 steps, providing important insight on the design and rational improvement of efficient photon upconversion systems. Ongoing detailed mechanistic studies of the TET1 process shows that both QD bright and dark exciton states contribute to the TET process and higher lying bridge states play significant role in enhancing TET from core/shell QDs.
(Invited) Electrochemistry-based and electrochemistry-coupled characterization of lithium ion based battery materials and systems
Authors: Marschilok Amy C.
Published: November 2022

Lithium ion batteries are ubiquitous in our everyday lives and have revolutionized portable electronics and the transportation industry. As self contained energy storage systems, lithium ion batteries often appear as black boxes. However, the chemistry inherent to their function is diverse and complicated. Examples of mechanistic insight gained from in situ and operando characterization of lithium ion batteries will be highlighted in this presentation. This will include approaches to spatially locate and resolve productive and parasitic processes in functional energy storage materials and systems, with an emphasis on electrochemistry-based and electrochemistry-coupled approaches.
Mechanistic Li-Ion Battery Modeling, What's Next?
Authors: Dubarry Matthieu , Beck David
Published: November 2022

While relatively young, the mechanistic modeling approach has proven extremely versatile and effective for Lithium-ion battery diagnosis and prognosis and it has gained tremendous traction in the past decade. The approach is relying on digital twins built from different matchings of the individual voltage response of each electrode. The digital twins enable quantification of the degradation modes and open the gate for material-based diagnosis and prognosis without the need for complex models. From previous work in our laboratory, the method allowed to conceptually explain counter intuitive concepts such as hidden degradation mechanisms, overdischarge induced capacity, and the sudden apparition of knees.

This presentation will reflect on a decade worth of discussion and validation of several of the key concepts of digital twins for advanced diagnosis and prognosis since the seminal publications in the early 2010s. It will also introduce the next chapter with several new directions to enhance its application to more complex case figures. In the past decade since proposing our version of the framework, it was used to diagnose the degradation of several hundred cells of multiple chemistries and blends. It made possible to explain and predict the apparition of knees with the concept of hidden mechanisms and to emulate the impact of kinetics. The approach also proved useful to investigate overdischarge, overcharge, and to generate big-data with millions of synthetic voltage curves enabling the development of advanced diagnosis and prognosis tools. Looking forward, the approach can still be improved and some new directions will be detailed here with proof-of-concept simulations. This includes the simulation of blended and inhomogeneous electrodes that are destined to play a big role for the diagnosis and prognosis of next generation cells. Moreover, calculations could be done outside of constant current which could allow a much wider field implementation of better diagnosis and prognosis tools for deployed systems.
(Invited) Electrostatic Site Potential in Electrolytes As an Emerging Descriptor for Reversible Metal Electrodes
Authors: Takenaka Norio , Ko Seongjae , Yamada Atsuo
Published: November 2022

In order to maximize the electrochemical stability of a battery with metal anode, suppressing the side reaction between the metal and the electrolyte is essential. When the deposition potential positions outside of the stability window, optimization of SEI is a general approach to realize kinetic hinderance of side reactions. While another effective approach should be upshifting the deposition potential itself because it makes the side reactions much slower and milder, or even thermodynamic stability could be gained if the potential is upshifted into the stability window of the electrolyte.

It is well known that electrode potentials vary significantly depending on the electrolyte. Typical example can be found in salt concentrated electrolyte, where the metal deposition potential significantly upshifts over 0.5 V upon increasing the concentration. However, the mechanism behind the potential shift has remained unclear.

By careful analyses of the local coordination environment by molecular dynamics simulations and the accurate experimental measurement of the deposition potential, we revealed that the potential shift is primarily determined by electrostatic destabilization of metal cations rather than the simple Nernst-type expression depending on cation activity. The shallow site potential of metal cations is attributable to the dominant coordination to more charge-dispersive, larger size anions rather than to relatively electro-positive solvents, thus decreasing the overall Coulombic energy gain of metal cations. Such simple yet hitherto-overlooked mechanism can be a useful guideline in the development of better electrolytes for reversible metal electrode.
(Invited) Drx and Drx+ As Earth-Abundant Inexpensive Cathodes
Authors: Ceder Gerbrand
Published: November 2022

Scaling the Li-ion industry to multiple TWh/year will be challenging with NMC-class cathodes because of the cost and resource constraints arising from the use of nickel and/or cobalt. Disordered rocksalt cathodes DRX can be synthesized with almost any transition metal and offer a likely alternative to replace Ni-containing layered cathode materials. Since their invention in 2014 understanding and performance improvement of DRX materials has made significant progress. Materials based on Mn and Ti, which can be synthesized from inexpensive precursors, have shown that specific energies between 650 to 850Wh/kg can be maintained during extended cycling. The ability of these materials to substitute some O by F also provides them with excellent stability even up to high voltage. Since they lose little or no oxygen when highly charged, they are also like to provide high safety.

Rate capability, which early on posed a problem for DRX cathodes, has been improved through multiple strategies, and 200mA/g and higher rates can now be achieved without substantial capacity loss. Because these compounds can be synthesized from standard Mn-oxide and Ti-oxide precursors they have the potential to be a low-cost, resource abundant alternative to NMC class materials.
An Investigation on the Factors Affecting Self-Discharge in Li/CFx-MnO2 Hybrid Primary Batteries
Authors: Yoon Hyunki , Yeo Jae-Seong , Yoo Eunji , Cho Jang-Hyeon , Choi Yusong
Published: November 2022

Lithium/Carbon fluoride (Li/CFx) primary batteries have been used in commercial applications, for example implantable cardiac pacemakers, due to their high energy density, long shelf life, and wide operation temperature range (-40oC to 85oC). However, the low electrical conductivity of CFx leads to a serious initial voltage delay at the beginning of discharge and the low rate capability of Li/CFx primary batteries. To overcome these issues, CFx materials are mixed with manganese dioxide (MnO2) to form hybrid cathodes due to a good rate capability of MnO2. Generally, the electrolytic manganese dioxide (EMD) used as cathode materials in Li/MnO2 primary batteries contains about 5% of water before heat treatment. The pristine EMD materials were heat-treated to reduce the water contents. However, water can be reabsorbed by cathode materials during processing and cathode formation. In this study, we investigated the effects of residual water contents in the pristine heat-treated EMD materials and as-fabricated CFx-MnO2 cathode electrodes on the self-discharge characteristics in Li/CFx-MnO2 primary batteries. Moreover, we investigated the effect of protective film on Li anode surface on the self-discharge characteristics in Li/CFx-MnO2 primary batteries. A protective film on Li anode surface was formed by immersing it in the electrolyte or carbon dioxide treatment. We believe that this study will provide useful guidance in the enhanced electrochemical properties and fabrication process of Li/CFx-MnO2 primary batteries.
Extenuation of Jahn-Teller Distortion By Ti and V Co-Doping in P2 Type Sodium Iron Manganese Oxide Cathode
Authors: Banik Trapa , Bhattacharya Indranil
Published: November 2022

Among all the prevailing cathode materials for Sodium-Ion Battery (SIB), the Manganese and Iron rich P2 type Na2/3Fe1/2Mn1/2O2 (NFM) has attracted broad attention as a promising cathode candidate due to the natural abundancy of Fe and Mn along with high redox couple of Fe3+/Fe4+ and Mn3+/ Mn4+. Despite all these merits, NFM suffers from structural instability during cycling arising from the destructive Jahn-Teller (JT) distortion effect of Mn3+/ Mn4+ during charging and Fe4+/ Fe3+ during discharging. This study investigates how the elemental doping process effectively alleviates the JT effect. Here, in this research, a tiny fraction two electrochemically inactive elements, Titanium (Ti) and Vanadium (V) are incorporated in Mn-rich cathode that mitigated the JT effect substantially and ameliorated the stability of the SIB during cycling. A moderate amount of doping preserves the lattice structure and similar morphology to pristine NFM which is attested from FESEM and EDS mapping results. Besides, the Ti and V co-doping in place of Fe not only effectively reduced the amount of JT prone Mn3+, which is observed through in-depth material analysis such as XRD and XPS, but also increased the specific capacity by expanding the d-spacing for Na ion transport that are reflected through various electrochemical analysis.
Water/Ionic Liquid/Succinonitrile Hybrid Electrolytes
Authors: Reber David , Borodin Oleg , Becker Maximilian , Rentsch Daniel , Thienenkamp Johannes H. , Grissa Rabeb , Zhao Wengao , Aribia Abdessalem , Brunklaus Gunther , Battaglia Corsin , Kuehnel Ruben-Simon
Published: November 2022

The water-in-salt concept has significantly improved the electrochemical stability of aqueous electrolytes, and the hybridization with organic solvents or ionic liquids has further enhanced their reductive stability.[1] Here, we open a large design space by introducing succinonitrile as a cosolvent in water/ionic liquid/succinonitrile hybrid electrolytes. Via addition of the nitrile, electrolyte performance metrics such as electrochemical stability, conductivity, or cost can be tuned, and salt solubility limits can be fully circumvented. We elucidate the solution structure of two select hybrid electrolytes and highlight the impact of each electrolyte component on the final formulation, showing that excess ionic liquid fractions decrease the lithium transport number, while excess nitrile addition reduces electrochemical stability and yields flammable electrolytes. If component ratios are tuned appropriately, high electrochemical stability is achieved and aqueous Li4Ti5O12 - LiNi0.8Mn0.1Co0.1O2 full cells show excellent cycling stability with a maximum energy density of ca. 140 Wh/kg of active material, and Coulombic efficiencies of close to 99.5% at 1C. Furthermore, strong rate performance over a wide temperature range, facilitated by the fast conformational dynamics of succinonitrile, with a capacity retention of 53% at 10C relative to 1C is observed.[2]

References:

[1] Becker, M.; Rentsch, D.; Reber, D.; Aribia, A.; Battaglia, C.; Kühnel, R.-S., The hydrotropic effect of ionic liquids in water‐in‐salt electrolytes. Angew. Chem. Int. Ed..
2021, 60, 14100.

[2] Reber, D.; Borodin, O.; Becker, M.; Rentsch, D.; Thienenkamp, J.H.; Grissa, R.; Zhao, W.; Aribia, A.; Brunklaus, G.; Battaglia, C.; Kühnel, R.-S., Water/Ionic Liquid/Succinonitrile Hybrid Electrolytes for Aqueous Batteries. Adv. Funct. Mater.
2022, 2112138.
Isoindigo-Derived Organic Small-Molecules As Long-Lifespan and High-Rate Cathode Materials for Rechargeable Batteries
Authors: Park Jong-Jin , Yoon Seong-Jun , Kim Jinsang , Kwon Ji Eon
Published: November 2022

Redox-active organic molecules (ROMs) are promising electrode materials for next-generation rechargeable batteries owing to their beneficial advantages of environmental friendliness, natural abundance, low cost, and possible high theoretical capacity. However, they suffer from a serious dissolution problem in organic electrolytes and low electrical conductivity, limiting their practical application. In particular, despite many advantages such as easy synthesis, potential low cost, and convenient processing, small-molecule electrode materials have typically showed far inferior stability and rate performance than polymeric materials.

Herein, two isoindigo-based small molecules, isoindigo (Me-IIG) and thienoisoindigo (Me-TIIG), were synthesized and evaluated as a cathode material in lithium-organic batteries. In a Li coin cell, Me-IIG and Me-TIIG electrode exhibited specific capacity of 156 and 168 mAh g-1 at 1C, corresponding to 84% and 95% of capacity utilization, respectively. The Me-TIIG with better planar molecular geometry than the Me-IIG showed much lower solubility in organic electrolytes with the aid of strong intra- and intermolecular interactions. As a result, the Me-TIIG electrode presented remarkably improved cycling stability, retaining 96% of the initial capacity after 500 cycles at 5C rate. Moreover, Me-TIIG exhibited lower reorganization energy than Me-IIG, which can facilitate a kinetically faster electrochemical pathway, leading to superior rate capability. It should be noted that the Me-TIIG electrode showed excellent rate performance achieving 70% capacity retention at a high rate of 20C.
Substoichiometric Titania As Viable Supports for Direct Electrodeposition of Electrocatalysts for Fuel-Cell Relevant Reactions
Authors: Alamgir Faisal M. , Alabbady Abdulaziz , Bell Crystal N , Lee dong Chan
Published: November 2022

One of the obstacles to long-term performance of fuel cells is the corrosion carbon support for the electrocatalysts. Titania (TiO2), with its robust corrosion resistance, is already used as a catalyst support for a range of reactions. However, with a bandgap of around 3 - 3.4 eV depending on the type of polymorph, it is too insulating to serve as an electrocatalyst support. In this study, we explored the electrical and the corrosion-resistance properties of substoichiometric titania, specifically the Ti2O3 and the Ti3O5 phases, in order to assess whether they may be as plausible carbon-free supports for electrocatalysts. Furthermore, we investigated the efficacy of synthesizing low-dimensional Pt, Pd, and combined Pt-Pd based catalysts directly onto substroichimetric titania through iterative electrodeposition steps. The influence of the electrodeposition parameters on the physicochemical and electrochemical properties of Pt particles was investigated using x-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), x-ray absorption spectroscopy (XAS) and cyclic voltammetric techniques. Along with CV analysis, XPS confirmed the successful deposition of (Pt,Pd)-based electrocatalysts onto Ti2O3 and Ti3O5 supports. XAS confirmed that the local atomic structure of the catalysts exhibited the crystalline order expected from Pt and Pd. SEM analysis showed that the electrochemical deposition conditions used in this work favored the formation of particles with hierarchical fractal-like morphologies. Accelerated stress testing (AST) for the oxygen reduction reaction (ORR) using modified DOE protocols were performed to investigate the catalyst stability. After 30K AST cycles, the active electrocatalyst area retained relative to the as-prepared catalysts was ~14 and 22% for electrocatalysts electrochemically deposited on Ti2O3 and Ti3O5, respectively.

Figure 1
Regulating Electrochemical Growth of Metals at Rechargeable Battery Electrodes
Authors: Zheng Jingxu , Archer Lynden A. , Checkelsky Joseph
Published: November 2022

Control of crystallography of thin metal electrodeposit films has recently emerged as key to achieving long operating lifetimes in next-generation electrochemical systems for energy storage. Very recent studies show that the crystallography of metal deposits impacts both morphological evolution and chemical kinetics of the interfaces between metal anodes and electrolytes in a battery. We report that the large crystallographic heterogeneity, e.g., broad orientational distribution, that appears characteristic of commercial metal foils results in rough morphology upon plating/stripping. On this basis, we develop an accumulative roll bonding (ARB) methodology—a severe plastic deformation process—that uses commercial metal foils as input. Zn metal—a promising, low-cost-competitive battery anode material— is used as a first example to interrogate the proposed concept. We demonstrate that the ARB process is highly effective in achieving uniform, mono-domain quality crystallographic control on macroscopic materials. After the ARB process, the Zn grains exhibit a strong (002) texture (i.e. [002]Zn//ND). We report further that the texture transitions from a classical bipolar pattern to a nonclassical unipolar pattern under large nominal strain, almost completely eliminating the orientational heterogeneity of the foil. Evaluated as anodes in aqueous Zn coin cells, the strongly (002)-textured Zn suppresses the rough plating/stripping landscape, promotes uniform, homoepitaxial growth of Zn and remarkably improve the continuous plating/stripping performance by nearly two orders of magnitude under practical conditions (e.g., 4 mAh at 40 mA/cm2). The performance improvements are readily scaled to achieve pouch-type Zn full batteries that deliver exceptional reversibility. The ARB process is thermo-mechanical and can in principle be applied to any metal chemistry to achieve similar crystallographic uniformity, provided the appropriate temperature and accumulated strains are employed to achieve severe levels of plastic deformation. We evaluate this concept using ARB to induce strong texturing phenomena in commercial Li and Na foils, which unlike Zn (HCP) are BCC crystals, and demonstrate its success using morphological and electrochemical analysis of these metals as electrodes. Our simple process for creating strong textures in both hexagonal and cubic metals and illustrating the critical role such built-in crystallography plays underscores potentially transformative opportunities for developing scalable, highly reversible thin metal anodes (e.g. hexagonal Zn, Mg, and cubic Li, Na, Ca, Al) with specific crystal textures for next generation batteries that have practical N:P ratios.

Key References:

Zheng, J., et al.
Advanced Materials
34.1 (2022): 2106867.

Zheng, J., et al.
Nature Energy
6.4 (2021): 398-406.

Zheng, J., et al.
Science Advances
6.25 (2020): eabb1122

Zheng, J., et al.
Science
366.6465 (2019): 645-648.
Electrochemical Reduction of Active Metals in Aqueous Systems: An Electron Withdrawing Ligand Approach to Deposit Highly Adherent Oxide Layers
Authors: Nulwala Hunaid , Zhou Xu
Published: November 2022

The electroplating of active metal in water is extremely challenging. The oxidative reactivity of active metals such as aluminum and zirconium metal leads to a very negative reduction potential. It makes the reduction in the presence of water impossible. Current active metal deposition is performed under inert conditions.

We have utilized a unique ligation approach; we can create aluminum species that remain stable in water and lower the reduction potential for aluminum by 0.5V. This lowering of reduction potential allows us to electrochemically reduce aluminum in water and compete with hydrogen evolution. With this platform we are able to deposit highly adherent layers of aluminum oxide layers on metal surfaces. The aluminum oxide layers are thin, coherent and highly adherent coatings. This aluminum oxide layer can then be chemically adapted to achieve previously inaccessible surface properties. For example, the coating can be made hydrophobic, highly adherent to different polymer coatings and a great tie layer to grow ceramic coatings.

We will be discussing the initial theory in reduction potential and then sharing the results of our work.
(Electrodeposition Division Early Career Investigator Award) Understanding and Controlling Electrodeposition of Li in Solid Electrolytes
Authors: Han Fudong
Published: November 2022

The successful integration of Li metal anode with solid electrolytes seems to be a must for a high-energy-density solid-state battery. However, Li dendrites tend to form in solid electrolytes during Li plating. The formation of dendrites has been observed in solid electrolytes with various crystal structures from glass, glass-ceramic, poly-crystalline to single-crystalline materials, but the mechanism of such an unexpected dendrite growth remains elusive. In this presentation, I will introduce our understandings of lithium dendrite formation in solid electrolytes based on operando neutron depth profiling characterizations. The results highlight the important role of electronic conduction in solid electrolytes in the formation of isolated Li dendrites in solid electrolytes. I will then present our recent results in understanding the intrinsic value, voltage dependence, and charge carrier of electronic transport in typical lithium solid electrolytes. Lastly, I will introduce corresponding strategies to suppress dendrite formation in solid-state Li metal batteries.

Reference
s
:

[1] F. Han, A. S. Westover, J. Yue, X. Fan, F. Wang, M. Chi, D. N. Leonard, N. J. Dudney, H. Wang, C. Wang, Nature Energy, 4 (2019) 187.

[2] F. Han, J. Yue, X. Zhu, C. Wang, Advanced Energy Materials, 8 (2018) 1703644.

[3] F. Han, J. Yue, C. Chen, N. Zhao, X. Fan, Z. Ma, T. Gao, F. Wang, X. Guo, C. Wang, Joule, 2 (2018) 497.

[4] X. Fan, X. Ji, F. Han, J. Yue, J. Chen, L. Chen, T. Deng, J. Jiang, C. Wang, Science Advances, 4 (2018) eaau9245.

[5] R. Xu, F. Han, X. Fan, J. Tu, C. Wang, Nano Energy, 53 (2018) 958.

[6] Y. Huang, B. Shao, F. Han, Current Opinions in Electrochemistry, 33 (2022) 100933.

[7] Y. Huang, B. Shao, F. Han, Journal of Materials Chemistry A, 10 (2022) 12350.

[8] F. Han, Y. Zhu, X. He, Y. Mo, C. Wang, Advanced Energy Materials, 6 (2016) 1501590.

[9] F. Han, T. Gao, Y. Zhu, K. J. Gaskell, C. Wang, Advanced Materials, 27 (2015) 3473.
Scanning Electrochemical Cell Microscopy: A Tool for Nanoscopic Deposition of Light-Driven Photocatalysts
Authors: Oswald Eva , Gaus Anna-Laurine , Romer Jan , Kund Julian , von Delius Max , Kranz Christine
Published: November 2022

Single and multi-barrel nanopipettes and nanopipette-based scanning electrochemical probe microscopy techniques like scanning electrochemical cell microscopy (SECCM) have gained significant attention as tools for localized, maskless, three-dimensional surface modifications [1,2]. The nanometer-sized orifices of nanopipettes allow delivering molecules to solution inducing concentration-confined electrodepositions. Also, electroless nanoscale depositions like the fountain pen technique [3] can be achieved by this technique.

In this study, we present the deposition of various cobaloxime-based earth-abundant Co catalysts for light-driven hydrogen evolution reaction (HER) [4]. Arrays of different cobalt(III) complexes were deposited via SECCM and investigated in respect with their HER activity using scanning electrochemical microscopy (SECM) in combination of Pd-microsensors [5] for in situ hydrogen (H2) measurements under illumination. In addition, AFM studies revealed possible degradation of the commercially available neutral benchmark complex [Co(dmgH)2(py)Cl] in these studies. First results will also be presented in respect with the deposition of nanowires via co-deposition of HER catalyst and Ruthenium photosensitizer. First spatially resolved photocatalytic studies at such nanowires, which are characterized by high surface area, will be presented. Also, the influence of the substrate will also be discussed.

References:

Oswald, K. Palanisamy, C. Kranz, Curr. Op.
Electrochem. 34, 100965 (2022).

Hengsteler et al., Nano Lett. 21, 9093 (2021).

-H. Kim, N. Moldovan, H.D. Espinosa, Small 1, 632, (2005).

Oswald et al., Chem. Eur. J. 27, 16896 (2021) and corrigendum (2022); doi:10.1002/chem.2022008809.

Kund et al., ChemElectroChem 9, e202200071 (2022)

Funding by the German Science Foundation (DFG) – project number 364549901 – TRR 234 (projects B7, C4).
(Digital Presentation) Electrodeposition of Re on Aerosol Jet Printed Metal Seed Layers on Flexible Substrates
Authors: Tsui Lok-kun , Ahammed Kamal , Sui Yongkun , Weigel Emily A , Huang Qiang , Lavin Judi
Published: November 2022

Quantum computers (QCs) are expected to run advanced algorithms to solve currently intractable challenges in chemistry simulations, cryptography, medicine, and finance.[1] The Josephson Junction based qubits that power a quantum computer must reside in a cryogenically cooled chamber at 10 mK. Communications with this chip is currently carried out with a chandelier of rigid cables.[2] A flexible cable containing superconducting interconnect lines could in principle simplify the design of QC interconnects and lead to improvement in qubit density and efficiency. We have previously demonstrated the use of aerosol jet printing (AJP) for the patterning of electrodeposited Cu and Ni [3]. We have also recently reported on the development of a water-in-salt method to electrodeposit superconducting Re on evaporated Au on Si substrates. These Re components have a critical temperature above 4.2 K, which makes the superconductivity easily accessible with liquid He cooling[4].

We report for the first time the metallization of flexible Kapton substrates with printed Au and Ag nanoparticle inks by aerosol jet printing as the seed for superconductor electrodeposition. Electrodeposition of Re onto the printed structures was performed using the water-in-salt method. ASTM D3359 tests demonstrated that Au has superior adhesion to Kapton, while the Ag seed does not survive rhenium deposition, potentially due to the high internal stress of Re. Further, improved adhesion was demonstrated when Kapton substrates were roughened with 1200 grit sandpaper. Electrodeposited Re on AJP Au seed layer on flexible Kapton substrates, as shown in Figure 1, demonstrated a superconducting transition temperature of 6K. In addition, electrodeposited Re on Au survived 200 cycles of flexure testing under >30 MPa load and 1.2% strain. These efforts demonstrate the proof-of-principle for patterning of superconducting interconnects for the further development of QCs.

SNL is managed and operated by NTESS under DOE NNSA contract DE-NA0003525. SAND2022-11522 A

References

[1] F. Bova, A. Goldfarb, and R.G. Melko “Commercial Applications of Quantum Computing.” EPJ Quantum Tech. (2021) 8:2.

[2] S. Krinner, S. Storz, P. Kurpiers, P. Magnard, J. Heinsoo, R. Keller, J. Lütolf, C. Eichler & A. Wallraff. “Engineering cryogenic setups for 100-qubit scale superconducting circuit systems.” EPJ Quantum Tech. (2019) 6:2.

[3] L. K. Tsui, S. C. Kayser, S. A. Strong, and J. M. Lavin, “High Resolution Aerosol Jet Printed Components with Electrodeposition-Enhanced Conductance.” ECS J. Solid State Sci. Tech. (2021). 10, 047001.

[4] W. D. Sides, E. Hassani, D. P. Pappas, Y. Hu, T. S. Oh, Q. Huang “Grain growth and superconductivity of rhenium electrodeposited from water-in-salt electrolytes.” J. App. Phys. (2020). 127, 085301.

Figure 1. (a) Photograph of a well adhered Re on Au sample. (b) Superconducting transition data for Re on printed Au on Kapton.

Figure 1
Direct Recycling of End-of-Life Li-Ion Cathode Materials through Redox Chemistry Mediators
Authors: Kirwa Cyrus Kibichi , Coyle Jaclyn , Luo Hongmei
Published: November 2022

Recycled lithium-ion (Li-Ion) battery materials are pivotal for the sustainability of the renewable energy industry. Widespread consumer and municipal adoption of electric vehicles (EVs) directly correlates to the increased demand for Li-Ion batteries. Increasing Li-Ion battery production to meet the demand presents two challenges: end-of-life (EoL) Li-Ion management through recycling and mineral depletion. Li-Ion batteries are manufactured with hazardous and volatile materials, hence, cannot be sent to landfills. Therefore, recycling is vital in preserving the environment and securing resources. The current research uses wet chemical separation of spent Li-Ion battery electrode materials. The method used in direct recycling of the delithiated Li-Ion cathode materials through redox chemistry mediators employs reduction and oxidation chemistry. Quinone compounds shuttles charges between lithium metal or lithium salt and delithiated cathode materials. This redox reaction occurs at low temperature to restore lithium content in the spent Li-ion battery electrode materials. The process recovers the lithium content in the cathode materials without negatively affecting the structure. The half-cell electrochemical performance is comparable to pristine material. Hence, redox chemistry relithiation for direct recycling is promising.

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Electrochemically Modulated CO2 Removal from Oceanwaters
Authors: Kim Seoni , Rufer Simon , Lake Jack , Nitzsche Michael , Kang Jin Soo , Varanasi Kripa , Hatton T. Alan
Published: November 2022

As the concentration of carbon dioxide is continuously increasing, there have been a lot of efforts to remove CO2 from various sources. While most of the attention has been focused on CO2capture at point sources followed by geological storage, interest in negative emission strategies also increased recently. One of the promising approaches for negative emissions is removing CO2 from ocean water. The world ocean is the largest carbon sink, containing 120 times higher concentration compared to the atmosphere. Therefore, by removing CO2 from ocean water, we can expect a reduction in CO2 concentration in the atmosphere.

Considering that the CO2-reduced oceanwater should be returned to the ocean, the addition of chemicals, and the formation of undesirable compounds should be avoided. In this respect, the electrochemical approach can be a good choice because it does not require additional chemicals, and the control of voltage can tune the reactions in the system. Until now, several approaches have been made by using the electrodialysis process. However, the use of bipolar membrane for water dissociation makes this process expensive, making the application of this process sluggish.

In this talk, we will present a new membrane-free approach based on electrochemical modulation of the pH to release the CO2 from ocean water. After removing CO2, the treated water is alkalized before being returned to the ocean. Using an electrochemical pH swing approach, we could successfully remove the CO2 from ocean water without employing expensive membrane or additional chemicals.
pH Modulation in the Membrane Capacitive Deionization (MCDI) Cell Using Bipolar Membrane (BPM)
Authors: Kulkarni Tanmay , Arges Christopher G.
Published: November 2022

This work investigates bipolar membranes (BPMs) for pH modulation of process streams in a membrane capacitive deionization (MCDI) device. Exploiting Pourbaix diagram knowledge, it was posited that control of electrode potential and process stream pH can enable selective ion removal and recovery from process streams that have ionic species mixtures. For example, making a process stream pH can etch silica particles to silicate or convert boron to borate and make these species susceptible to removal via ion-exchange. A BPM can make an organic acid process stream alkaline for organic acid anion removal via ion-exchange. It can acidify streams to make metals conducive for plating on electrode surfaces. The use of BPMs in Electrodialysis cells (BPM-ED) has been an established technique to attain a particular pH in the cell. However, the ionic separation in the ED cell occurs through the ion-exchange membranes which makes it difficult to differentiate between competing ions in mixtures containing target ions at very low concentrations (e.g., ppm level or less). Prior to using BPM-MCDI for selective ionic separations, this work discusses how BPM properties (onset potential, polarization behavior, etc.) and MCDI cell parameters (operating voltage, feed concentration, residence time, etc.) govern process stream pH.
(Invited) In-Situ Stress Measurement during Electrochemical Processing
Authors: Stafford Gery
Published: November 2022

The electrochemical community often uses in situ wafer curvature and cantilever bending techniques to examine stress development during electrochemical processing. These techniques have been used to examine and quantify surface stress induced by surface charge (electrocapillarity), adsorption processes, and growth stress associated with underpotential deposition (UPD) and electrodeposition. The sensitivity of the stress measurement to surface processes makes this technique particularly relevant for electrochemical studies. For example, we have used in situ surface stress measurements to examine the underpotential deposition of a variety of metals (M) onto (111)-textured Au cantilever electrodes. The stress response clearly shows regions of anion desorption, M–Au bond formation, and in some cases, stress relaxation that can be attributed to surface alloying. This talk will focus on the surface and growth stress that develops during a variety of electrochemical processes, including metal deposition, the formation of elastically strained Pt films for electrocatalysis, and adsorbate-induced surface stress, such as carbon monoxide (CO) on Pt.
(Invited) Management Systems for Lithium-Ion Batteries
Authors: McCann Gerry
Published: November 2022

Battery management systems (BMS) for large Li-ion batteries are, of themselves, complex systems. The complexity starts with voltage measurement for individual cells. Large batteries may have 96, 192, or more, series connected cells, so requiring complex wiring harnesses. The high noise environment provides additional challenges for wiring and also analog front end and analog to digital conversion system design. For safety, and to help with state-of-charge (SOC) estimation, temperature sensors must be located throughout the battery. A computational infrastructure estimates SOC for each cell. The estimate is typically based on cell voltage, measured current, estimated cell resistance, integrated current and temperature. Additionally, cell capacity imbalance, whether present from the start or evolved over time, must be corrected.

This talk will attempt to provide some insight into BMS design for mass-produced large batteries. The applications, whether for electric vehicles (EV) or stationary storage, are generally safety critical, so placing additional demands on the BMS. Typically, the BMS also manages the interaction between the battery and the remainder of the system. It sets limits for allowed charge and discharge currents and can interrupt current and disconnect the battery if limits are exceeded. This area will also be addressed, with a particular focus on fusing challenges for EV applications. Power transfer of 500 kW or more may be required. Depending on the application this may be for only a few seconds, or it may be indefinite. In additional to safety, reliability is also critical. For example, the many required cell connections must remain intact for the intended service life of the installation. This will be addressed, touching also on design of the overall battery pack.
(Invited) Photoelectrochemical Processing of Semiconductor Devices
Authors: Kohl Paul
Published: November 2022

Many of the chemical processes used to fabricate and metallize semiconductor devices are based on oxidation-reduction reaction. Electro-chemical processes using the semiconductor itself have the advantage of being able to photo-generate the reactants within the semiconductor to carryout local reactions. The development of photoelectrochemical methods to process features in semiconductor devices is a subject unique to the Electrochemical Society because it is at the intersection of electrochemistry and semiconductor device fabrication. Specific symposia at ECS meeting have explored these subjects. In particular, Noel Buckley was a motivating force behind the State-of-the-Art Program on Compound Semiconductors (SOTAPOCS) symposium series which offered venues for presenting interdisciplinary results of this kind. In this talk, several examples of chemical and photoelectrochemical processes for semiconductor device manufacturing from past ECS SOTAPOCS symposia, organized by Noel Buckley, will be described.
(Invited) The Long Reach of Impedance Measurements: From Flow Cells and Dielectrics to Experimental Artifacts
Authors: Vanysek Petr
Published: November 2022

The motivation for this presentation is to bring into perspective experience in collecting and interpreting impedance data and put this in interesting and relevant form in front of specialists in electronic materials and processing.

Impedance spectroscopy became very popular among electrochemists ever since most modern potentiostats started incorporating hardware for collecting impedance and software, for interpretation of putative equivalent circuits. The popularity stems both from usefulness of the method, when judiciously applied, and from the ease to obtain graphs suitable for pondering their meaning. In fact, the method became so commonplace that it acquired the acronym EIS which electrochemists somewhat vainly explain as the electrochemical impedance spectroscopy even though in many situations, it is spectroscopy just electrical as there may not be electrochemical processes even going on.

The current turnkey potentiostats give capable electronic instrumentation to hands of people who do not need to be experts in electronic circuitry. This can lead to overinterpretation of data, particularly at higher frequencies. We will show on a case study how real-life input impedance of the instrument, which is typically and often successfully, ignored in data interpretation, can contribute to appearance of additional elements in fitted equivalent circuits.

With the turnkey hardware is also provided powerful software as a tool for assignment of physical or chemical properties of the studied sample. On a case study of a dielectric electronic material with a leakage we will show how interpretation with overlooked leakage contribution leads to incorrect interpretation of material permittivity, indicating its frequency dependence.

The attached figure shows impedance response of an active mass in a lead-acid battery studied for purpose of modern application for energy recuperation. This is one data set for an active lead acid mass 80 % discharged from a series of a full set of 0-100% discharged and 0-100% charged steps. The interpretation complication arises from the high frequency data (emphasized in the inset), where an inductor as an element in equivalent circuit might be called for. We will demonstrate how this response can be contributed to the real-life behavior of the impedance analyzer itself.

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(Invited) Atomically-Precise Surface Processes: From Molecular Mechanisms to Realistic Devices
Authors: Teplyakov Andrew
Published: November 2022

The atomic-level precision in designing surfaces and nanostructures is quickly making its way from the one-off laboratory investigations into chemical manufacturing. However, in order to make the applications feasible, fundamental understanding of the mechanisms of surface reactions leading to the formation of the desired surface structures is needed. A great deal of progress has been made over the years in uncovering reactions behind atomic layer deposition (ALD), but much more limited information is available about atomic layer etching (ALE), although both processes are often required to build the components of present and future microelectronics.

This talk will highlight recent work on understanding the reactions for metal and metal oxide deposition on functionalized (and patterned) surfaces and on recent advances in ALE of complex materials, specifically focused on tertiary alloys, such as CoFeB, used in magnetic tunnel junctions. I will outline the work needed to understand the mechanisms of these processes that can be further used to improve the control over atomically-precise manufacturing methods and to reduce the use of hazardous procedures. The relatively well-understood ALE procedures that include oxidation or chlorination as the first half-cycle of ALE of such materials and introduction of a bidentate ligands (such as acetylacetonates) to remove complex materials uniformly and with atomic-level control will be extended to describe the potential use of much milder conditions and reagents. A combination of experimental and computational methods will be used to make this analysis possible.