bluuebunny/crossref_metadata_2025_split huggingface dataset:
TiO2 Channel Material for Lithium-Ion-Gated Neuromorphic Transistors
Authors: Alvarez Ana , Schroeder Marshall A. , Boltersdorf Jonathan , Theodoru Stefan , Hoerauf John , Grew Kyle N. 
Published: August 2024

Ubiquitous Internet of Things (IoT) platforms have exponentially increased the relay of an abundance of data between memory and processor in current computing architectures, ultimately limiting throughput and advancing towards the von Neumann bottleneck. Brain-inspired computing using neuromorphic devices presents an encouraging alternative framework capable of power-efficient real-time inference, self-learning, and decision-making. This work focuses specifically on ion-gated, three-terminal transistors that rely on electrochemically driven ion intercalation between an electronically insulating electrolyte and a conducting channel. While other nonvolatile memories (NVMs) can be used in neuromorphic devices, electrochemical random-access memory (ECRAM) advantageously enables the programming of multi-states and their retention in the absence of applied power. This talk will present our recent work on anatase TiO2 as a channel material in a lithium-ion-gated, three-terminal transistor. Based on the literature, anatase TiO2 covers a wide channel conductance range and exhibits a linear response, allowing for numerous well-defined synaptic weights [1]. We explore a range of channel conductance values using both potentiostatic and galvanostatic pulsing and correlate material properties to electrical measurements. These results provide a benchmark and roadmap for lithium-ion-based neuromorphic transistors capable of multi-states.
[1] Y. Li, E.J. Fuller, S. Asapu, S. Agarwal, T. Kurita, J.J. Yang, and A.A. Talin, ACS Appl. Mater. Interfaces
11, 38982 (2019).
(Invited) Bio-Inspired Time Varying Networks for Novel Computing Primitives
Authors: Kohlstedt Hermann 
Published: August 2024

As a result of a hundred million years of evolution, living animals have adapted extremely well to their ecological niche. Such adaptation implies species-specific interactions with their immediate environment by processing sensory cues and responding with appropriate behavior. Understanding how living creatures perform pattern recognition and cognitive tasks is of particular importance for computing architectures: by studying these information pathways refined over eons of evolution, researchers may be able to streamline the process of developing more highly advanced, energy efficient autonomous systems.
With the advent of novel electronic and ionic components along with a deeper understanding of information pathways in living species, a plethora of opportunities to develop completely novel information processing avenues are within reach.
Basal biological principles are highlighted, including phylogenies, ontogenesis, and homeostasis, with particular emphasis on network topology and dynamics. While in machine learning, system training is performed on virgin networks without any a priori knowledge, the approach proposed here distinguishes itself unambiguously by employing growth mechanisms as a guideline to design novel computing architectures. Within this framework, experiments on low-frequency relaxation type oscillators coupled via complex time-varying networks will be presents. The spatio-temporal development of the network results from a mutual interaction between the oscillator ensemble and the network structure. The blooming and pruning of suddenly appearing conductive bridges and their relation to the synchrony state of the oscillator ensemble will be discussed.
Integrated Insights into NH4
+ Storage Mechanism and Electrochemical Kinetics of Ultrastable Prussian Blue Analogues
Authors: Zheng Runtian , Su Bao-Lian 
Published: August 2024

Ammonium-ion batteries (AIBs) have recently attracted increasing attention in the field of aqueous batteries owing to their high safety and fast diffusion kinetics.[1, 2] The NH4
+ storage mechanism is quite different from that of spherical metal ions (e.g. Li+, Na+, K+, Mg2+, and Zn2+) because of the formation of hydrogen bonds between NH4
+ and host materials. As one of the main host materials, PBAs with 3D channels have been extensively investigated in AIBs. The formula for PBAs can be roughly expressed as AxMm[Mn(CN)6]y·zH2O, where A represents the cation (e.g. Na and K) for charge compensation, Mm and Mn stand for transition-metal ions (e.g. Cu, Ni), respectively. m, n, x, and y are their stoichiometric values. The size of the channels in PBAs is about 0.32 × 0.32 nm, which is larger than the ionic radius of NH4
+ (0.154 nm). In this work, the NH4
+ storage mechanism during the charging/discharging process is investigated by in-situ XRD and showed stable structure. In addition, the DFT calculation further demonstrates the insertion/extraction mechanism. During the NH4
+ insertion process, hydrogen bonds are formed between the hydrogen atom in NH4
+ and nitrogen atom in PBAs framework, which is beneficial for electrochemical and structural stability.
References
[1] H. Yu, L. Fan, H. Yan, C. Deng, L. Yan, J. Shu, Z.-B. Wang, Inorg. Chem. Front. 2022, 9, 2001-2010.
[2] X. Wu, Y. Qi, J.J. Hong, Z. Li, A.S. Hernandez, X. Ji, Angew. Chem. Int. Ed. 2017, 56, 13026-13030.
Synergy of Silicon-Graphene Anodes and Polymer-Ceramic Hybrid Separators for High Rate-Capable Lithium-Ion Batteries
Authors: Joshi Yash Milind , Jain Ritika , Joo Yong Lak 
Published: August 2024

With more and more electric vehicles (EV) hitting the market, the need for better and more robust energy storage system increases, and silicon has been a promising candidate for the next generation anode material to satisfy the high energy density and high-power requirements for electric vehicles because of its extremely high theoretical capacity. This has allowed the design of thinner electrodes to reduce the diffusion time scales and deliver a fast charge. However, at high charge and discharge rates, low electrical conductivity (~1.12 eV) of silicon hampers the battery performance. As a result, a lot of research has been conducted to improve the performance of silicon anodes using nanoscale carbon to increase the electrical conductivity. Graphene has been used to synthesize Si/Gr hybrid anodes due to its high conductivity.
Graphene nanoribbons (GNRs) , a part of the graphene family, are one-dimensional graphene nanostructures which tune its electrical properties based on dimensional confinement. GNR has a higher conductivity than Graphene. It also has high aspect ratio and surface area to provide a strong conductive path along with mechanical strength to support the silicon anode. Due to presence of GNR, lithium-ion transport into silicon nanostructures was enhanced. As a result, 50% of graphene was replaced by 50% GNR with silicon nanoparticles to form anodes. Due to the highly conducting structure of GNR, capacity at high rates was significantly improved because of the improved silicon utilization. Since GNR’s dimensions are in nanometer range, connection with silicon nanoparticles is better. It not only improves silicon to silicon conductivity, but it also acts as a filler for better connection of graphene with silicon nanoparticles.
Addition of graphene nanoribbons can improve the lithium-ion transport within the anode but to enhance the high charge transfer rate further, Si/GNR/Gr hybrid, high rate-capable anodes were paired with Polyimide (PI)/Polysilsesquioxane (PSSQ) hybrid separators which also shown to exhibit an improved charge transfer rate. At high rates such as 3C and 5C, the effect of separator on the cell performance becomes more prominent. While Celgard’s performance was very unstable at both 3C and 5C, at 3C, the cycling of hybrid separators did not get impacted, despite the relatively harsher conditions. This synergistic combination of high-rate capable silicon/graphene anode and hybrid separator outperformed the commercially used separator especially at high-rate cycling. Cells with Si/GNR/Gr anode paired with the PI/PSSQ separator delivered an impressive capacity of 1,000 mAh/g at high charge/discharge rates of 5C/5C.
Investigating the Synthesis Pathway of a Disordered Rocksalt Phase Via in Situ X-Ray Characterization
Authors: Liang Zhilin , Marques Otavio , Masina Sikhumbuzo , Paredes Mellone Oscar , Sokaras Dimosthenis , Weker Johanna Nelson , Stone Kevin 
Published: August 2024

Recently, Li-rich disordered rocksalt (DRX) materials have gathered a lot of attention as prospective Li-ion battery cathode materials owing to their high electrochemical storage capacity and high specific energy. In contrast to the current commercialized layered Li-ion battery cathode materials (e.g. LiCoO2, LiNixMnyCo1-x-yO2), which contain toxic and expensive metals, DRX can accommodate a large variety of transition metals, such as Mn and Ti, which are cheap and earth abundant. These characteristics make them a cheaper and a more sustainable alternative to the current commonly used layered cathodes.
Unlike the commercial Li-ion battery cathodes, where the transition metals and the Li are arranged in an ordered manner, DRX exhibits a highly disordered cation framework. Fluorine incorporation into DRX was extensively studied, where the fluorine anions are distributed disorderly at the anion sites. Previous studies have shown that the electrochemical performance of DRX cathodes can be enhanced via fluorination, as fluorine can effectively suppress the oxygen redox activity observed in many Li-rich cathodes. However, a large degree of fluorine incorporation into DRX was found to be difficult. As a result, it is important to study the mechanism in which fluorine is incorporated into the structure, and the role of LiF during synthesis of DRX.
In addition to fluorination, the degree and type of short-range cation ordering (SRO) presenting in the materials were also found to have a significant impact on the electrochemical performance of DRX materials. The SRO present can be modified with synthesis techniques, where samples annealed at the synthesis temperature for a longer period exhibit a higher degree of SRO. This observation has demonstrated that the synthesis conditions and SRO are highly correlated. It is hence possible to control the SRO in DRX materials via varying synthesis conditions, thereby enhancing their electrochemical performance. Keeping this in mind, it is hence important to understand the mechanism by which DRX is formed.
In this work, we have performed in situ synchrotron X-ray diffraction monitoring the phase progression during the solid-state synthesis of Li1.1Mn0.8Ti0.1O1.9F0.1 DRX oxyfluoride. We have observed several crystalline intermediate phases emerged before the formation of the DRX phase. Coupled with X-ray absorption spectroscopy, we are able to gain additional insights into the intermediate phases formed during the synthesis. This poster will describe the investigation of the synthesis pathway of Li1.1Mn0.8Ti0.1O1.9F0.1 DRX oxyfluoride using X-ray characterization techniques. The formation mechanism of this DRX phase will also be discussed.
The Impact of Biomass-Derived Graphene-like Porous Carbon Decorated with NiO Nanoparticles on the Electrochemical Performance of Lithium-Sulfur Batteries
Authors: Sultanov Fail , Dangaliyeva Akmaral , Tatykayev Batukhan , Mentbayeva Almagul , Bakenov Zhumabay 
Published: August 2024

Lithium-sulfur batteries are considered a promising next-generation energy storage system, boasting high theoretical capacity and energy density, approximately double that of LiBs [1,2]. However, challenges such as low sulfur conductivity, significant volume expansion during cycling, and the lithium polysulfides shuttle effect hinder their practical use [3]. These issues result in side reactions, irreversible loss of active material, and anode degradation, leading to a rapid decline in cell capacity stability [4].
In this research, we successfully developed a sulfur cathode carbon matrix and separator modifier from rice husk through carbonization and thermal activation. The resulting graphene-like porous carbon (GPC) exhibited high efficiency as a sulfur host, enhancing the electrochemical performance of the cathode. The GPC-NiO composite also served effectively as a separator modifier, catalyzing lithium polysulfides' redox reactions and improving the overall cycling stability of lithium-sulfur batteries. In particular, the GPC@S/GPC-NiO-20 cell demonstrated an excellent initial discharge capacity of 1519 mAh g-1 at 0.2 C. Also, it delivered excellent long-term cycling, maintaining a discharge capacity of 661 mAh g-1 even after 400 cycles at 1 C, with a Coulombic efficiency exceeding 97%. It exhibited a promising rate capability of 568 mAh g-1 at 2 C and retained a discharge capacity of 603 mAh g-1 over 100 cycles at 0.2 C with a sulfur loading of 4.0 mg cm-2.

Acknowledgments

This research is funded by the Science Committee of the Ministry of Science and Higher Education of the Republic of Kazakhstan (Grant No. AP19677708).

References

[1] H. Li, S. Ma, J. Li, F. Liu, H. Zhou, Z. Huang, S. Jiao, Y. Kuang, Altering the reaction mechanism to eliminate the shuttle effect in lithium-sulfur batteries, Energy Storage Materials. 26 (2020) 203–212. https://doi.org/10.1016/j.ensm.2020.01.002.
[2] F. Sultanov, A. Mentbayeva, S. Kalybekkyzy, A. Zhaisanova, S.-T. Myung, Z. Bakenov, Advances of graphene-based aerogels and their modifications in lithium-sulfur batteries, Carbon. 201 (2023) 679–702. https://doi.org/10.1016/j.carbon.2022.09.069.
[3] M. Zhao, Y.-Q. Peng, B.-Q. Li, X.-Q. Zhang, J.-Q. Huang, Regulation of carbon distribution to construct high-sulfur-content cathode in lithium–sulfur batteries, Journal of Energy Chemistry. 56 (2021) 203–208. https://doi.org/10.1016/j.jechem.2020.07.054.
[4] Y. Hu, W. Chen, T. Lei, Y. Jiao, J. Huang, A. Hu, C. Gong, C. Yan, X. Wang, J. Xiong, Strategies toward High‐Loading Lithium–Sulfur Battery, Adv. Energy Mater. 10 (2020) 2000082. https://doi.org/10.1002/aenm.202000082.
(Invited) Sensing the Nanoscale Dynamics and Dimensionality of Brain Tissue By 3D Localization Microscopy of Diffusing Carbon Nanotubes
Authors: Grésil Quentin , Nandi Somen , Mangalwedhekar Rohit , Simon Apolline A. , Cognet Laurent 
Published: August 2024

Elucidating how the nanometric structure of complex environments shapes the mesoscopic motion of the nano-objects within them is a fascinating but still open question. Due to a lack of knowledge of nanoscale details, diffusion properties are often described as anomalous. This applies to many systems, including the brain extracellular space that is the focus of this study. Its structure is indeed heterogeneous and tortuous, and ions, nutrients and signaling molecules diffuse in it for proper function of the brain.
In recent years we have developed a strategy based on single-particle localization microscopy using SWIR emitting single-walled carbon nanotubes (SWCNTs) to decypher this brain compartment[1] but also pathological livers[2]. We now show that 3D tracking is essential to link the anomalous diffusion often observed at the macroscale to the local microscopic topologies of the edifices. We will present our recent results for the study of brain extracellular space [3], and other applicable structures including biophysical structures.

References

[1] Godin et al Nat Nano 12 (2017) 238 ; Soria et al Nat Commun 11 (2020)3440 ; Paviolo et al, Nano Lett. (2022) 6849-6856
[2] A.A. Simon 10.26434/chemrxiv-2023-15tgf.
[3] Gresil et al, in preparation
(Invited) Developing a Graphene Field-Effect Biosensor for Genetic Biomarkers: Simulations Unveil How the Device Sensitivity Is Related to DNA-Graphene Interactions at the Nanoscale
Authors: Cote Sebastien , Tremblay Louis , Sauvage Madline , Bouilly Delphine 
Published: August 2024

Graphene field-effect transistor biosensors (GFETs) offer a promising platform to detect cancer DNA biomarkers at low concentration [1]. At their core, they have an electronic circuit containing a graphene sheet – a two-dimensional nanomaterial made of a single layer of carbon atoms – whose electronic properties are very sensitive to nearby electric charges. Leveraging that feature, the electrical current generated by a GFET can thus be made very sensitive to the concentration of a specific DNA sequence in a biological sample. To achieve this, the complementary DNA sequence is linked to the graphene to bind specifically the target DNA. In most GFETs, the link is done using 1-pyrenebutanoic acid succinimidyl ester (PBASE) because its pyrene group stacks on the graphene through pi-pi interactions, without disrupting the electronic properties of the graphene. However, recent experiments in the Bouilly group have shown variations in GFET sensitivity depending on the incubation time of graphene with PBASE.
Here, we use a computational approach developed in our previous work [2] to investigate at the nanoscale the role of PBASE linker molecules on the sensitivity of the GFET. First, we use molecular dynamics simulations to characterize the conformational ensemble of a 10-nt single-stranded DNA sequence linked to a graphene sheet using PBASE. Second, we estimate the electrical response of the GFET from the electrostatic potential generated by these DNA conformations on the graphene, as determined using electrostatic Poisson-Boltzmann simulations. Our results show that the conformational ensemble of DNA is strongly affected by the presence of other PBASE adsorbed on the graphene, thus changing the electrostatic potential generated on the graphene. The predicted change of the electrostatic potential should impact measurably the detection signal of the GFET.
We are now using these simulations to explain the experimental characterizations of a GFET designed to detect a genetic biomarker important in breast cancer profiling. Our simulations have the potential to support the development of GFETs with better sensitivity for DNA detection.
[1] Béraud, A., Sauvage, M., Bazán, C. M., Tie, M., Bencherif, A., and Bouilly, D. (2021) Graphene field-effect transistors as bioanalytical sensors: design, operation and performance. Analyst. 146:403-428.
[2] Côté, S., Mousseau, N., and Bouilly, D. (2022) The molecular origin of the electrostatic gating of single-molecule field-effect biosensors investigated by molecular dynamics simulations. Phys. Chem. Chem. Phys. 24:4174-4186.
SC-CNTs: Thin Film Transistors for High-Performance, Low-Power, Flexible Electronics
Authors: Humes Jefford Jason 
Published: August 2024

Single Walled Carbon Nanotubes (SWNTs) have gained a great deal of media attention over the past almost-two decades. From their theoretical usage as the foundational material for space elevators that would take travelers beyond earth’s atmosphere, to an active material that would allow engineers to create nanobots that internally repair or treat the human body, applications for SWNTs are numerous and have resonated within the imagination of scientists and the media alike. Fast forwarding to the modern era, we find that nanotubes still have a great deal of technological promise, some of which parallel those usages that were theoretically conceived many years ago.
For over a decade, NanoIntegris Technologies Inc. has been at the forefront of synthesizing high-purity, electronically enriched SWNT’s and, during that time, has found that our materials have proven to transcend from the theoretical to practical-usage realm. With over 1,900 publications citing the usage of NanoIntegris’ high performance materials, we have not only seen the beneficial properties of our materials studied via techniques such as scanning electron microscopy but have also received many positive use-cases for our materials such as being an additive of highly-conductive, electrode (anode/ cathode) slurries of next-generation lithium-ion batteries, to being used as an active for the highly-sensitive detection of COVID antigens.
Within my talk, I will display the usage of our high-purity semiconducting (≥99%) single walled carbon nanotubes to make the next generation of high-performance electronics. I will focus upon the usage of our IsoSol-S100 semiconducting solution that served as the spin-coated semiconducting layer within a short channel (<10 µm) thin film transistor with ON/OFF of 104, a device thickness of 400 nm, and a mobility of 39 cm2V-1s-1. I will further discuss the usage of our IsoNanotubes-S 99% solution to serve as the active material within a low-power, wearable Radio Frequency biosensor that covers the GSM spectra, with an operation frequency up to 2.1GHz, and that can serve as both a frequency multiplier and mixer.
P-Doped Carbon Nanotubes As Light Absorbers and Electron Donors in Photovoltaics
Authors: Blackwell Christopher J. , Dhavamani Abitha , Faitz Zac , Zanni Martin , Arnold Michael S. 
Published: August 2024

Doping is a ubiquitous and powerful tool used to alter a material’s electronic properties. Conventional Si solar cells would not exist without it, and it has been used to increase the efficiency of organic and inorganic photovoltaics alike. While doped carbon nanotubes (CNTs) have been the subject of numerous spectroscopic studies, few investigations have examined their performance in photovoltaic devices. Here, we incorporate chemically p-doped CNTs into photovoltaic heterojunctions with C60. In a conventional CNT–C60 heterojunction device, photocurrent can be produced when photogenerated excitons in the CNT layer diffuse to the CNT–C60 heterointerface. The offset in conduction band energy drives dissociation of these excitons via photoelectron transfer from CNT to C60, which yields separated charges that can be collected. Our objective here was to determine the following: 1) does p-doping increase or decrease the efficiency with which excitons dissociate into electrons and holes? 2) Do p-dopants trap excitons and inhibit their diffusion to the heterointerface? 3) How efficiently can a photogenerated trion (exciton coupled to an injected hole) be dissociated to produce a photocurrent?
To answer these questions, we fabricated polymer wrapped (6,5) CNT–C60 heterojunctions over a range of CNT thickness with various levels of p-doping introduced by triethyloxonium hexachloroantimonate treatment. We measured photocurrent to quantify relative photoelectron transfer efficiency for both excitons and trions and compared this to photoluminescence and transient absorbance measurements on doped CNT films. We found that p-doping decreases photocurrent because injected holes bleach the CNTs’ S11 transition and decrease the amount of light absorbed. Meanwhile, the photogenerated exciton to collected electron transfer efficiency remains unchanged for doping densities up to 50μm-1. In contrast, photoluminescence quantum yield drops by over 90% at an equivalent doping density. We attribute this disparity to the fast electron transfer at the CNT–C60 interface, which occurs on the order of femtoseconds. We also found that moderate doping can promote photocurrent at the trion peak, with a photogenerated trion to collected electron transfer efficiency about 1/4 that of the photogenerated exciton to collected electron transfer efficiency. Photocurrent at the trion absorption peak is invariant with reverse bias up to 0.3 V, despite the charged nature of the trion, supporting evidence for the immobile nature of trions. These results indicate that p-CNTs are a viable material for use in photovoltaics, albeit with weaker absorption, and that photocurrent from trions is possible, although with lower quantum efficiency.

Figure 1