bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimizing the Electron Transfer Efficiency in a Conductive Biomimetic Polymer Electrode for Microbial Fuel Cell Applications
Authors: Deninger Ian D. , Shanahan Caitlin J. , Sran Ashna K. , Keleher Jason J.
Published: July 2022

Incorporating biomimetic polymers to develop a conducting nanocomposite material is a viable solution to address the problematic charge-transfer limitations that are common to carbon-based electrodes. Additionally, the variability associated with reported power density performance is due to the wide variety of carbon electrode functionalization techniques. Therefore, the efficacy of a biomass-based (i.e., polysaccharides and cellulose) electrode is due to the controlled establishment of a porous, non-covalent, polymer network which can serve as a consistent starting material for further functionalization. The scope of this work aims to utilize the existing biopolymer backbone (i.e., agarose, alginate, and cellulose) as a carbon scaffold to selectively control the photochemically initiated radical polymerization of conductive polymer (i.e., aniline, pyrrole) uniformly throughout the composite. Initial results indicate that the photochemically initiated polymerization of polyaniline and polypyrrole improved the efficacy of chain growth and established more uniform distributions of conducting polymer throughout the composite matrix. Current-voltage sweeps (I-V) of electrodes incorporated with polyaniline showed enhanced charge transfer when compared to polypyrrole systems at similar applied potentials. These results indicate that the absolute electron transfer performance is related to the molecular structure of the conductive polymer network. Polyaniline has a greater structural capacity to resonate electron density throughout the conjugated network, despite containing more dielectric material. In addition, the electron transport performance and efficiency of this biomimetic electrode has been shown to depend on the identity of the incorporated photoinitator (i.e., Fe3+), as well as the type of dopant (i.e., hydrochloric acid, sulfuric acid, polyelectrolyte), and surrounding polymer backbone (i.e., alginate, agarose, cellulose). Preliminary findings on dopant effects indicated markedly faster rates of charge transfer in electrodes doped with sulfuric acid. Furthermore, an extension of these enhanced current-voltage properties has been applied into a mediator-less E. coli MFC system, which exhibited increased open circuit potentials comparable to carbon cloth.
Electrokinetic Preconcentration and Label-Free Electrical Detection of Sars-Cov-2 RNA at a Packed Bed of Bioconjugated Microspheres
Authors: Claus Echo LeeAnn , Strait Madison , Anand Robbyn Kimberly
Published: July 2022

In diagnostics, point-of-care (POC) devices, such as lateral flow assays, play an important role due to their ease of use, practical application, and fast response. However, one of the major limitations of POC devices is low sensitivity. To address this limitation, electrokinetic techniques have been utilized to enrich the target analyte prior to detection. In one such technique, ion concentration polarization (ICP), an ion depleted zone (IDZ) is formed near an ion permselective membrane or electrode following the application of an external electric field. The low conductivity of the IDZ supports the formation of an extended electric field gradient. Enrichment arises from focusing of a charged analyte along this electric field gradient in the presence of opposing fluid flow. ICP focusing is a reliable technique for the enrichment and mobility-based separation of charged species, such as DNA, RNA, or proteins. However, ICP focusing is negatively impacted by electroconvective vortices that drive unwanted mixing.

We utilize an out-of-plane faradaic ion concentration polarization (fICP) technique that employs a 3D porous electrode and an adjacent packed bed of insulating microbeads to improve the stability of the enriched plug. In this work, we exhibit the detection of SARS-CoV-2 RNA, extracted from lysed virus, at subpicomolar concentrations in this microfluidic device. Here, the insulating beads are bioconjugated with an uncharged peptide nucleic acid (PNA) oligoprobe that hybridizes with the target RNA. The resulting increase in negative charge on the bead surface leads to a shift in a current-voltage curve between the 3D electrode and a driving electrode at the microchannel inlet. This shift in conductivity serves as a non-optical sensing mechanism for detection of the hybridized SARS-CoV-2 RNA. Most notably, this enrichment and sensing scheme utilizes off-the-shelf streptavidin-modified beads, making it highly versatile, while the reagent-free approach and low driving voltage render it amenable to POC implementation.

This work is supported by a grant from the Roy J. Carver Charitable Trust.
Measuring DNA Charge Transport on a Surface Using a Redox Modulated Fluorescence Intensity Strategy with DNA SAMs
Authors: Ma Tianxiao , Ma Tianxiao
Published: July 2022

The double stranded DNA helix has drawn great attention across different research areas. Various types of platforms have been used to study DNA charge transfer (CT) system. Two types of DNA CT platforms are considered as the most effective: the photoinduced CT in solution with assembled donor and acceptor and electrochemistry on ground state CT in a DNA self-assembled monolayer (SAM)1. We will show a new approach for the study of DNA CT on gold surface by studying the redox modulated fluorescence signal of a co-deposited double-stranded DNA assemblies labeled with Methylene Blue (MB) or AlexaFluoro488 (AF488). We demonstrate a method that can optically distinguish between the two mechanisms of the MB redox on DNA-modified surface: namely either DNA CT mediated reduction or the direct reduction of MB by the gold surface2. Given the fact that the studies on DNA-mediated electrochemistry on surface has been mainly using electrochemical measurements and we still do not fully understand the full picture of the DNA CT, we believe that this study will provide a fresh opinion and facilitate understanding on the DNA CT mechanism on electrode surface.

Reference:

Arnold, A. R.; Grodick, M. A.; Barton, J. K. DNA Charge Transport: From Chemical Principles to the Cell. Cell Chem. Biol.
2016, 23 (1), 183–197.

Pheeney, C. G.; Barton, J. K. DNA Electrochemistry with Tethered Methylene Blue. Langmuir
2012, 28 (17), 7063–7070.

Muren, N. B.; Olmon, E. D.; Barton, J. K. Solution, Surface, and Single Molecule Platforms for the Study of DNA-Mediated Charge Transport. Chem. Chem. Phys.
2012, 14 (40), 13754–13771.
Lithium-Ion Battery Second Life: Cell Performance Assessment for Stationary Energy Storage Applications
Authors: Platt Alison , Fatih Khalid , Brueckner Shawn , Yuan Xiao-Zi , Jang Darren , Fuller Eric
Published: July 2022

Repurposing electric vehicle (EV) lithium-ion batteries (LIBs) for second-life applications in stationary energy storage has developed considerable interest. With EV sales continuously rising, some critical materials used in LIBs risk supply shortages, while the volume of spent batteries could begin to overwhelm the facilities capable of disposing or recycling them. EV batteries typically reach end-of-life (EOL) when the capacity fades by 20-30%; although this is EOL exclusively for automotive applications, there still remains plenty of residual energy storage available that can be further utilized for less demanding applications. If viable, this could have significant impact in satisfying economic and environmental concerns as the trend toward greener and more sustainable energy solutions gains momentum. Extending the lifespan of retired EV LIBs can potentially supplement and soften the demand for total product, relaxing the strain on newly manufactured product and changing the standard of practice in the value chain. This lifecycle expansion could also be beneficial with respect to environmental impact by reducing raw material extraction and processing, landfill disposal or recycling, and improving resource sustainability.

Existing public work on the reuse of EV batteries has mostly been exploratory, including feasibility studies, techno-economic analyses, and promotional demonstrations. Although necessary as part of the framework to move forward, these investigations lack the data to demonstrate the reliability of EV batteries for second-life applications. The work presented herein utilizes the International Electrotechnical Commission (IEC) standard 62620:2014 to evaluate the compliance, in terms of both capability and longevity, of EOL EV cells for energy storage applications.

Battery modules were obtained from consumer-utilized 2012 and 2014 Nissan Leafs and characterization tests were applied to determine the present state of health. Cells were electrically isolated and the IEC Standard’s electrical tests were applied using a de-rated capacity as the new nominal capacity, based on the characterization results. One of the seven IEC Standard tests included a 500-cycle endurance test in which a C/2 charge and discharge rate was applied. Electrochemical impedance spectroscopy was measured periodically throughout the endurance test. Results on the compliance of these cells for stationary energy storage applications will be presented and discussed.
(Invited) The Recell Center: Improving the Economics of Lithium-Ion Battery Recycling
Authors: Spangenberger Jeffrey
Published: July 2022

The ReCell Center, a Department of Energy's, Vehicle Technologies Office managed program led by Argonne National Laboratory, is working to develop and demonstrate, battery recycling technologies that improve the economics of responsible end-of-life lithium-ion battery management. This presentation will provide a brief summary of ReCell’s work and the progress it has made over the past 3 years of it existence.
(Invited) Toward Solvent-Based Direct Recycling of Lithium-Ion Batteries
Authors: Belharouak Ilias , Bai Yaocai , Essehli Rachid
Published: July 2022

Lithium-ion batteries are booming globally for the applications in electric vehicles, consumer electronics, grid energy storage, and so on. The high demand and production of LIBs drives the generation of vast stockpiles of spent LIBs in near future. Recycling of those waste LIBs not only alleviates the environmental impacts from disposal in landfills and reduces the influences of raw mineral extraction and refining, but also reduces costs and lowers risks of supply chain disruptions. However, the recycling of LIBs is not taking off due to many fundamental and technological challenges. It is thus imperative to develop cost-effective and environmentally sustainable recovery processes to recycle end-of-life batteries. In this context, this presentation highlights the advancements in direct recycling of lithium-ion batteries from different aspects through solvent-based separation and regeneration processes. First, several green solvent-based recovery processes to efficiently separate electrode materials from their current collectors will be presented. Next, an aqueous sequential separation process to separate both anode/cathode and electrode/current collectors will be highlighted. In addition to the solvent-based separation processes, we will discuss the direct regeneration of spent NMC cathode via a solvent-mediated relithiation process. The discussion will shed light on new solvent-based separation and regeneration processes as an enabling step towards direct recycling of LIBs.
(Digital Presentation) Electrochemical Relithiation Protocols for Restoration of Cycle Aged NMC Cathodes
Authors: Coyle Jaclyn , Verma Ankit , Colclasure Andrew M.
Published: July 2022

Recycling end-of-life (EoL) lithium-ion batteries is of great significance to provide additional transition metal resources and alleviate environmental pollution from electric vehicle battery wastes. This study provides essential understanding towards developing an electrochemical relithiation process that will restore lithium loss in EoL intercalation cathode materials. This electrochemical relithiation process is one of several relithiation options being considered as a part of a direct recycling process designed to increase the efficiency of battery recycling by maintaining the composition and morphology of EoL cathode materials. A unique benefit of electrochemical relithiation is that it provides a potential alternative to processes that require EoL to be returned to powder form and then recast. Electrochemically aged NMC cathode materials have been prepared and characterized to establish the extent of EoL material structural transformations and lithium loss. A model-informed experimental process is used to identify the optimal electrochemical relithiation protocol to minimize the time taken to relithiate EoL materials and maximize the amount of lithium restored. Protocols were evaluated based on their ability to enable rapid lithium intercalation, maintain or reinstate structural uniformity in the EoL material and fully restore lithium content. An optimal protocol was identified at elevated temperatures utilizing a novel scanning voltage step. This work is part of ReCell which is a collaborative effort to develop efficient and economical recycle and reuse methods for EoL battery cathodes.
Membraneless Electrolyzers for the Conversion of Brine into High-Value Products
Authors: Fraga Alvarez Daniela V. , Esposito Daniel V.
Published: July 2022

Desalination offers an approach to address the shortage of fresh water, however, the main concern is the generation of reject brine or concentrated saltwater that contains organic compounds, metals, and contaminants. Membraneless electrolyzers present a viable solution to convert the reject brine into H2 and O2, while simultaneously splitting it into acidic (HCl) and base (NaOH). They transport ions through a highly conductive liquid electrolyte instead of a membrane. The lack of a separator allows for operation in a wide range of pH environments and inhibits degradation and fouling issues found in conventional electrolyzers. In this study, a membraneless electrolyzer was 3D printed and a Pt|porous electrode and planar Pt|Ti-foil were used as the cathode and anode, respectively. The electrodes are a key component since that is where the reactions of interest (hydrogen and oxygen evolution reactions) occur. Hence, the distribution of Pt onto a carbon foam substrate in a uniform and asymmetric pattern was studied. Kinetic overpotentials and mass transfer limitations decrease when Pt nanoparticles are in a uniform pattern since it increases active sites resulting in faster kinetics. However, asymmetric catalyst placement controls where gaseous bubbles are generated and therefore decreases product crossover. The device’s ability to generate acid and base at different applied current densities and volumetric flow rates was investigated whereby at high current densities and low volumetric flow rates, the pH differential of the effluent streams broadens. However, at this condition, product crossover increases. Future work involves using in situ high-speed videography to determine the critical Damköhler number to unravel the achievable maximum pH while minimizing product cross-over.
Elucidating Pathways to Electrochemical Reduction of Furfural Via Tailoring Interfacial Environments Toward Selective Production of Valuable Furanic Chemicals
Authors: Liu Hengzhou , Patel Deep , Chen Yifu , Roling Luke T. , Li Wenzhen
Published: July 2022

Electrochemical reduction of biomass-derived feedstocks holds great promise to produce value-added chemicals or fuels driven by renewable electricity. However, mechanistic understanding of the aldehyde reduction toward valuable products at the electrode/electrolyte interface at the molecular level is still lacking. Herein, we studied the furfural reduction on Pb electrodes in acid conditions and elucidated the detailed pathways toward three key products: furfuryl alcohol (FA), 2-methylfuran (MF), and hydrofuroin. First, by coupling isotopic labeling and electrokinetics, we revealed that protons (H2O and H3O+) plays an important role in the hydrogenation pathway toward FA and MF. In particular, the study of product-selective kinetic isotopic effect of H/D and the surface property-dependent hydrogenation/deuteration pathway strongly impacted the generation of FA but not MF, which can be attributed to their different formation mechanisms: FA is produced from Langmuir-Hinshelwood pathway that need both adsorbed furfural and hydrogen, but MF produced from Eley-Rideal pathway that need proton directly from the electrolyte. Modifying the double layer by cations with large radii, we further correlated the product selectivity (FA and MF) with interfacial environments (local H3O+ and H2O content, etc). Combined methods, including pulsed electrolysis, electron paramagnetic resonance (EPR) spectroscopy, and DFT calculations, further suggested that the formation of hydrofuroin and FA shared one intermediate. Hydrofuroin is produced through the desorption of the intermediate as ketyl radicals followed by its self-coupling in the electrolyte, while FA is generated from further hydrogenation of that intermediate. The acquired into the electrochemical reduction of the aldehyde group in furfural to alcohol, alkyl, and dimer may be extended to other organic compounds with carbonyl group, such as 5-hydromethylfurfural, toward a sustainable electrochemical manufacturing of higher-valued chemicals from biomass feedstock.
Artificial Synapse Based on 1D/2D Hybrid Heterostructure
Authors: Eo Jung Sun , Shin Jaeho , Eo Jung Sun
Published: July 2022

Molecular functional devices have been investigated through the study of molecular structure and its corresponding discrete orbital states since it determines the transport behaviors. [1,2] In contrast to the conventional strategy, we have demonstrated a novel strategy and design rule for realizing molecular-scale functions based on the energy band engineering in molecular heterojunction with two-dimensional (2D) semiconductors [3,4]. Recently, we have designed molecular heterojunction selector and the nonlinearity design rule with the role of the molecular dipole moment orientation which controls the band bending of the 2D semiconductor [4]. Likewise, various role of the molecular self-assembled monolayer (SAM) in hybrid heterostructure device with 2D semiconductor can give a novel and diverse functionality to the device that it can be a powerful platform for the next-generation functional devices. We implemented ferrocene substituted alkanethiol SAMs, which is a redox active molecule [5], in 2D MoS2 field-effect transistor (FET) structure. The redox state (oxidation or reduction) of the SAM is controlled through the gate bias and the oxidized molecular states (Fc -> Fc+) can act as a localized gate at the interface between molecule/2D semiconductor (MoS2) which the conductance of the n-type MoS2 channel can be modulated. This MoS2 FET with non-volatile multistate MoS2 channel can be suggested as electrochemically programmed molecular heterojunction artificial synapse.

[1] L. A. Bumm, J. J. Arnold, M. T. Cygan, T. D. Dunbar, T. P. Burgin, L. Jones, D. L. Allara, J. M. Tour, P. S. Weiss, Science 271, 1705 (
1996),.

[2] H. Song, Y. Kim, Y. H. Jang, H. Jeong, M. A. Reed, T. Lee, Nature 462, 1039 (
2009).

[3] J. Shin, S. Yang, Y. Jang, J. S. Eo, T.-W. Kim, T. Lee, C.-H. Lee, G. Wang, Nat. Commun. 11, 1 (2020).

[4] J. S. Eo, J. Shin, S. Yang, T. Jeon, J. Lee, S. Choi, C.-H. Lee, G. Wang, Adv. Sci. 2101390 (2021).

[5] Y. Zhao, S. Bertolazzi, M. S. Maglione, C. Rovira, M. Mas-Torrent, P. Samori, Adv. Mater. 32, 2000740 (2020).
Surface Functionalisation and Electroless Plating of 3D-Printed Microstructures
Authors: Jodeiri Iran Keyvan , Foerster Aleksandra , Im Jisun , Tuck Christopher
Published: July 2022

A microelectrode with a large surface area is one of the essential components in biosensors, electronic implants, and energy harvesting systems. In particular, enzymatic biofuel cells and biosensors benefit significantly from microelectrodes with a large surface area to volume ratio because of the increased enzyme loading and hence improved the power density of the final devices. Therefore, the fabrication of microelectrodes with a large surface area will advance its application in devices. Projection-microstereolitography (PµSLA) offers the ability to fabricate three-dimensional and geometrically adjustable polymeric microstructures with well-defined complex shapes in microscale. 3D polymeric microstructures produced using PµSLA can be then coated with metal to achieve high conductivity. Microelectrodes have been created via 3D printing of polymeric structures followed by electroless plating. However, the weak adhesion of the metal to the polymer limits the practical use of the produced devices as electrodes. Here, we show the method to introduce thiol groups on the surface of PµSLA-generated polymeric microstructures to improve the adhesion between the polymer surface and gold thin film. Our results demonstrate that thiol groups on the polymer surface provide the anchoring site for gold deposition during electroless plating via gold-sulfur bonding, resulting in strong adhesion between the polymer surface and the gold layer and long-term microelectrode durability. The gold coated 3D microelectrode exhibits excellent electrical conductivity up to 1.4 × 107 S/m (35% of bulk gold). This method can offer exciting potential for constructing microelectrodes for architecture-specific applications in future energy, catalysis, and sensing.
Characterization of Garnet-Type Li6SrLa2Bi2O12 Solid Electrolyte for LiCoO2 Cathode Composite in All-Solid-State Battery
Authors: Sugimura Yuta , Akimoto Keigo , Inada Ryoji
Published: July 2022

Together with the development of inorganic solid lithium (Li) ion conducting materials for the use as solid electrolytes, the formation of intimate solid-solid interface between electrode active material and solid electrolyte is pivotal for realizing high performance all-solid-state Li-ion batteries (LiBs) with high safety and reliability. Oxide-based solid electrolytes have the advantages of good chemical stability and ease of handling, but for many of them, the high temperature processing is required for the densification, which may cause undesired side reactions with electrode active materials during the processing.

Although garnet-type oxide solid electrolyte Li6SrLa2Bi2O12 (LSLBO) has lower ionic conductivity than widely studied garnet-type Li7La3Zr2O12 (LLZO), LSLBO can be sintered at much lower temperatures than LLZO [1,2]. Therefore, there is a possibility to suppress the side reaction with electrode active materials during high-temperature sintering for fabricating oxide-based all-solid-state LiBs.

In this study, we prepared dense LSLBO or composites of LiCoO2 (LCO) cathode and LSLBO by hot pressing (HP). LSLBO densified at 750 °C for 1 hour showed high relative density of 95%. The densification temperature of LSLBO by HP confirmed in this work is 100–150 °C lower than Bi-doped LLZO with the formula of Li6La3ZrBiO12 (LLZBO) [3, 4]. Bulk and total (bulk + grain conductivity) ionic conductivity of LSLBO fabricated by HP attained to 2.1 × 10-4 and 1.1 × 10-4 S/cm at room temperature, which is much higher than LSLBO prepared by a conventional furnace sintering (FS) [1] and spark plasma sintering (SPS) [2]. The electrochemical stability of LSLBO at an electrical potential from 3 to 6 V vs. Li/Li+ was also confirmed by measuring the cyclic voltammogram.

From XRD analysis of mixed LSLBO and LCO powders after annealing, LSLBO and LCO were found to be thermally compatible at temperature below 800 °C and LCO-LSLBO composite densified at 700 °C for 1 hour by HP showed mixed conducting properties with both electronic and ionic conductivity of 10-5-10-4 S/cm at room temperature. From galvanostatic charge and discharge testing of sintered LCO-LSLBO composite sheet, we found that electrochemical performance of LCO is not degraded by co-sintering with LSLBO. These results suggest that LSLBO solid electrolyte can be applied for LCO cathode composite in oxide-based all-solid-state LiBs.

References

1. R. Murugan, W. Weppner, P. Schmid-Beurmann and V. Thangadurai, Mater. Sci. Eng. B 143, 14–20 (2007).

2. Y. Gao, X. Wang, Q. Sun, Z. Zhuang and Q. Fang, Front. Mater. Sci. 6(3), 216–224 (2012).

3. M. Wang and J. Sakamoto, Ionics 24, 1861–1868 (2018).

4. D. K. Schwanz, A. Villa, M. Balasubramanian, B Helfrecht and E. E. Marinero, AIP Adv. 10, 035204 (2020).
A Sobering Examination of the Feasibility of Aqueous Aluminum Batteries
Authors: Pastel Glenn
Published: July 2022

Aqueous aluminum (Al) batteries are posited to be a cheap and energy dense alternative to conventional Li-ion chemistries, but an aqueous electrolyte mediating trivalent aluminum cations (Al3+) warrants greater scrutiny. This study provides a rigorous examination of aqueous Al electrolytes, with the first compelling evidence for a dynamic octahedral solvation structure around the Al3+, without Al-OTf contact ion pairs, even at high concentrations. This solvation behavior and the concomitant, transient electrostatic hydrolysis of Al-OH2 ligands contrasts strongly with previously reported water-in-salt electrolytes, and occurs due to the high charge density of the Lewis acidic Al3+. Nuclear magnetic resonance spectroscopy and other physicochemical measurements quantitatively reveal how species activity evolves with concentration and temperature. This new understanding exposes practical concerns related to the corrosiveness of the acidic aqueous solutions, the degree of hydration of aluminum trifluoromethanesulfonate (Al(OTf)3) salt, and the grossly insufficient reductive stability of the proposed electrolytes (>1 V between HER onset and Al3+/Al). Collectively, these factors constitute multiple fundamental barriers to the feasibility of rechargeable aqueous Al batteries.

Table of Contents: We assess the challenges associated with aqueous aluminum electrolyte by investigating the solvation structure of the Al3+ Lewis acid in Al(OTf)3-H2O solutions. The deprotonation of water ligands in the first solvation sheath leads to early onset of hydrogen evolution in super-concentrated aqueous aluminum electrolyte.

Figure 1
Carbon Nanosheets Derived from Reconstructed Lignin for Potassium and Sodium Storage with Low Voltage Hysteresis
Authors: Jiang Keren , Tan Xuehai , Zhai Shengli , Li Zhi
Published: July 2022

Lignin is the second most abundant and the only nature polymer rich in aromatic units. Although aromatic unit-rich precursors often yield soft carbon after carbonization, the side chains in lignin crosslink with the aromatic units and form a rigid 3D structure which eventually leads to hard carbons. Through a graphene oxide-catalyzed decomposition and repolymerization process, we successfully reconstructed lignin by partially tailoring the side chains. Compared to directly carbonized lignin, the carbonized reconstructed lignin possesses significantly fewer defects, 86% fewer oxygen-functionalities, 82% fewer micropores, and narrower interlayer space. These parameters can be tuned by the amount of catalysts (graphene oxide). When tested as anode for K-ion and Na-ion batteries, the carbonized reconstructed lignin deliveries notably more capacity at low-potential range (especially for Na-storage), shows much-improved performance at high current density, and most importantly, reduces voltage hysteresis between discharge and charge process by more than 50%, which is critical to the energy efficiency of the energy storage system. Our study reveals that the voltage hysteresis in K-storage is much severer than that in Na-storage for all samples. For practical K-ion battery applications, the voltage hysteresis deserves more attention in future electrode materials design and the reconstruct ion strategy introduced in this work provide potential low-cost solution.

Figure 1
(Digital Presentation) Performance Improvement of Nickel-Rich Layered Cathodes for Li Batteries Based on Modified Solid State Reaction
Authors: Fung Kuan-Zong , Tsai Shu-Yi , Yang Jen-Hao
Published: July 2022

Lithiated metal oxides with layered structure used as the cathode may provide a high capacity and stable cycle retention, which is a desired property for lithium-ion batteries. Among them, NMC composed of Ni, Mn and Co as transition metal ions is considered a promising positive electrode. Due to high cost and toxicity of Co, Ni-rich layered oxide with substitution of Ni for Co content shows high capacity and adequate cycling performance. Recently, the fabrication of NMC adopting single-crystal (grain size: 1~6 μm) process tends to give better long-term performance than ones with particles in nanometer range.

In this study, LiNi0.8Mn0.1Co0.1O2 (NMC811) with substitution of Ni/Mn for Co were selected as the Ni-rich layered cathode investigated. Due to the low melting point of Li2CO3, the heating temperature/time of powder mixture become crucial to control the adequate grain size of to achieve better retention. The value of the I(003) /I(104) ratio in XRD pattern represent cation mixing in layered structure. And this parameter is closely related to its electrochemical properties. Discussion will be carried out based on the results of XRD analysis and the charge–discharge profiles and cycling performance.
Targeted Synthesis of Metal Dual Atom Electrocatalysts
Authors: Barrio Jesus , Pedersen Angus , Feng Jingyu , Titirici Magda , Stephens Ifan Erfyl Lester
Published: July 2022

Natural enzymes present within their structure active centres composed of earth-abundant metals in atomic proximity. Such active sites, dual atom catalysts, display a unique efficiency in catalytic processes such as the nitrogen conversion to ammonia, the production of ethylene through C-C coupling, or the oxygen reduction reaction in fuel cells amongst others.1,2 Theoretical calculations suggest that the high catalytic activity of dual atom catalysts arises from the different binding mode of reactant molecules to that of metal foils and single atom catalysts, which allows to break transition scaling relationships.3 Nevertheless, the experimental synthesis and characterisation of this class of materials is highly challenging.4 It is particularly difficult to avoid the formation of single atom catalysts or nanoparticles. In this work we show a general approach to fabricate bioinspired Fe dual atom catalysts in a nitrogen doped carbon support; we test the catalyst for the oxygen reduction reaction under acidic conditions. The catalyst exhibited an activity of 2.4 ± 0.3 A g-1
carbon at 0.8 V versus a reversible hydrogen electrode in acidic media, comparable to the most active in the literature. The two-step procedure leads to well defined Fe-based dimers. We characterised these materials by means of X-ray absorption spectroscopy (XAS) and scanning transmission electron microscopy. Our general approach providing a new towards targeted synthesis of dual atom electrocatalysts for energy-critical reactions.

References

(1) Chen, J. G.; Crooks, R. M.; Seefeldt, L. C.; Bren, K. L.; Bullock, R. M.; Darensbourg, M. Y.; Holland, P. L.; Hoffman, B.; Janik, M. J.; Jones, A. K.; Kanatzidis, M. G.; King, P.; Lancaster, K. M.; Lymar, S. V; Pfromm, P.; Schneider, W. F.; Schrock, R. R. Beyond Fossil Fuel–Driven Nitrogen Transformations. Science
2018, 360, eaar6611

(2) Lee, C. C.; Hu, Y.; Ribbe, M. W. Vanadium Nitrogenase Reduces CO. Science
2010, 329, 642

(3) Singh, A. R.; Montoya, J. H.; Rohr, B. A.; Tsai, C.; Vojvodic, A.; Nørskov, J. K. Computational Design of Active Site Structures with Improved Transition-State Scaling for Ammonia Synthesis. ACS Catal.
2018, 8, 4017–4024

(4) Pedersen, A.; Barrio, J.; Li, A.; Jervis, R.; Brett, D. J. L.; Titirici, M. M.; Stephens, I. E. L. Dual-Metal Atom Electrocatalysts: Theory, Synthesis, Characterization, and Applications. Adv. Energy Mater.
2021, 2102715

Figure 1
What Nanomaterials Can Do for Energy Storage: Production of Charged, Individualised Nanomaterials (CINs) As Novel Materials for Electrochemical Energy Storage Devices
Authors: Shutt Rebecca Roisin Christine , Miller Thomas Samuel , Howard Chris Anthony
Published: July 2022

Electrochemical energy storage devices, such as batteries and supercapacitors, allow us to store electrical energy as chemical energy. They are a vital component of the UK’s plans to achieve net-zero carbon emissions by 2050.1 Nanomaterials offer properties such as short ion diffusion distances, high percolation to form conductive networks, and structural frameworks that can withstand mechanical stresses from successive volume expansion-contraction cycles on insertion-deinsertion of guest ions. Thanks to these properties, incorporation of nanomaterials into electrochemical energy storage devices could allow them to store more energy, last longer, and cope with the load cycles required for grid storage.2 However, the use of nanomaterials in commercial devices is limited by their low density and tendency to agglomerate. In addition, established synthesis methods such as high energy sonication and Hummer’s method yield nanomaterials with properties that fall short of those predicted theoretically, by resulting in a distribution of few-layer materials, and introducing defects that might not benefit electrochemical performance.

This work uses highly reducing solutions, such as alkali metal-ammonia solutions or sodium naphthalide solutions, and subsequent spontaneous dissolution in polar aprotic solvents, to individualise nanomaterials and introduce negative charge to the surface in a single step (Figure 1).3,4 This produces exclusively monolayer, pristine, negatively-charged, individualised nanomaterials (CINs). This synthesis route can be applied to a wide range of materials, such as layered materials like graphite and transition metal dichalcogenides, as well as carbon nanotubes and other carbonaceous materials. The negative charge introduced can be used in subsequent synthesis steps to add functionality, grow nanoparticles, and control assembly into 3D structure. Using starting materials such as graphite, carbon nanotubes, and phosphorus,5 this work presents the application of these methods to investigate what new materials can be made. Furthermore, their electrochemical performance in batteries and supercapacitors is discussed.

References

1HM Government, Dep. Business, Energy Ind. Strateg., 2020, 1–38.

2E. Pomerantseva, F. Bonaccorso, X. Feng, Y. Cui, Y. Gogotsi, Science, 2019, 366, 969.

3P. L. Cullen, K. M. Cox, M. K. Bin Subhan, L. Picco, O. D. Payton, D. J. Buckley, T. S. Miller, S. A. Hodge, N. T. Skipper, V. Tileli, C. A. Howard, Nat. Chem., 2017, 9, 244–249.

4A. Clancy, J. Melbourne, M. S. P. Shaffer, J. Mater. Chem. A, 2015, 3, 16708–16715.

5M. C. Watts, L. Picco, F. S. Russell-Pavier, P. L. Cullen, T. S. Miller, S. P. Bartus, O. D. Payton, N. T. Skipper, V. Tileli, C. A. Howard, Nature, 2019, 568, 216–220.

Figure 1
(Nanocarbons Division Richard E. Smalley Research Award) Evolution of Nanocarbons in Energy Conversion and Storage
Authors: Kamat Prashant V
Published: July 2022

The discovery of fullerenes led to the exploration of their excited state and electron storage properties in 1990s. This wave of research quickly led to the growth of carbon nanotube research, followed by graphene based nanocarbon materials. After a span of more than three decades, we now have a better understanding of properties of these nanocarbons and how to utilize them in various applications. Of particular interest are graphene–semiconductor or −metal nanoparticle composites with the capability to function as efficient, multifunctional materials for energy conversion and storage. In particular, reduced graphene oxide (RGO) is a suitable composite substrate because of its two-dimensional structure, outstanding surface area, and electrical conductivity. The presentation will focus on common employed methods to design graphene oxide-semiconductor composite materials and examine key studies that characterize their excited state interactions. The favorable energetics of RGO for intercepting excited states and inducing charge separation, along with the ease of developing electrode materials with tailored properties make it an exceptionally important mediator for improving the performance of solar cells and photocatalyst arrays. Strategies to develop graphene composites and control electron capture and transport through the 2D carbon network will be discussed.
(Digital Presentation) Stable Organic Passivated Carbon Nanotube-Silicon Solar Cells with an Efficiency of 22%
Authors: Yan Jun , Zhang Cuili , Li Han , Yang Xueliang , Wan Lu , Li Feng , Qiu Kaifu , Guo Jianxin , Duan Weiyuan , Lambertz Andreas , Lu Wanbing , Song Dengyuan , Ding Kaining , Chen Jianhui , Flavel Benjamin S
Published: July 2022

The organic passivated CNT/Si solar cell is a new type of low-cost, high-efficiency solar cell, with challenges concerning the stability of the organic layer used for passivation. In this work, the stability of the organic layer is studied with respect to the internal and external (humidity) water content and additionally long-term stability for low moisture environments. It is found that the organic passivated CNT/Si complex interface is not stable, despite both the organic passivation layer and CNTs being stable on their own and is due to the CNTs providing an additional path for water molecules to the interface. With the use of a simple encapsulation, a record power conversion efficiency (PCE) of 22% is achieved and a stable photovoltaic performance is demonstrated. This work provides a new direction for the development of high-performance/lost-cost photovoltaics in the future and will stimulate the use of nanotubes materials for solar cells applications.
(Digital Presentation) Hydrophilic and Hydrophobic Carbon Nanotubes Combined into a Buckypaper As an Electrode for Li-O2 Batteries
Authors: Leal Silva Jean Felipe , Doubek Gustavo , Maciel Filho Rubens
Published: July 2022

With the decreasing costs of wind and solar power, these two energy sources are set to gain a sizeable share of the electricity market in the next years. To cope with the intermittency of these electricity sources, grid operators are required to develop new, inexpensive, and efficient energy storage facilities. One of the technologies being considered for such application is the Li-O2 battery, whose main advantage compared to state-of-the-art lithium-ion batteries is the prospect of higher energy density which might lead to decreased installation costs. Nevertheless, these batteries depend upon efficient mass transport of O2 inside the electrode to present suitable power density. In this work, a mix of hydrophilic and hydrophobic carbon nanotubes (CNT) was used to produce an O2 electrode with enhanced mass transport properties. Hydrophobic CNT were prepared via thermal treatment under Ar atmosphere at 850 °C for 2 h. Hydrophilic CNT were prepared via refluxing in 7 mol L-1 HNO3 solution for 4 h (~120 °C). Raman spectroscopy was used to analyze the quality of both types of CNT. Different proportions of hydrophobic and hydrophilic CNT were dispersed in solution with a surfactant using a probe sonicator. The solution was filtered using a 0.22 μm membrane and vacuum to produce a buckypaper. Batteries were assembled in a glove box using a Li electrode, a separator membrane (glass fiber), and the buckypaper as the O2 electrode. Galvanostatic discharge tests were carried out at different currents to analyze the impact of different qualities of CNT used in the making of the O2 electrode in the increasing demand for O2 in the battery at high currents. Scanning electron microscopy images were used to compare the morphology of the different electrodes before and after discharge. Results are expected to demonstrate a new method to increase the mass transport rates for O2 in Li-O2 batteries.

The authors gratefully acknowledge the support from FAPESP (the Sao Paulo Research Foundation, Grant Numbers 2018/16663-2 and 2017/11958-1), Shell, the strategic importance of the support given by ANP (Brazil’s National Oil, Natural Gas and Biofuels Agency) through the R&D levy regulation, and the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brasil (CAPES) - Finance Code 001.
(Invited) Zeolite-Templated Carbon As a Model Material for Electrochemical Energy Storage in Nanometre-Spaced Carbon Channels
Authors: Stadie Nicholas P.
Published: July 2022

Beyond lithium-ion battery (LIB) chemistries demand new electrode materials exhibiting unique features to accommodate the larger and/or multivalent active ions. Zeolite-templated carbon (ZTC) is an ordered microporous carbon scaffold that is molecularly thin, electrically conductive, and covalently connected in three dimensions. Its narrow pore size distribution is centered at 1.2 nm, permitting the introduction and ultrafast conduction of large molecular guests. In this work, we demonstrate the serviceability of ZTC as a stable cathode material across wide voltage ranges for both bulky, polyatomic anions (as in dual-ion batteries, DIBs, and/or hybrid capacitors, HCs) and multivalent cations (e.g., magnesium-ion batteries, MIBs) in high energy density and high power density electrochemical cells. Charge storage proceeds by a purely capacitive mechanism at the surface of ZTC, mated with the faradaic mechanism of metal plating and stripping at the anode. A suite of techniques including solid-state NMR spectroscopy sheds insight into the role of the solvent, anion, and cation in electrochemical insertion/deinsertion of the active ions within the microporous framework of ZTC.

Figure 1
Microalgae Derived Nano Carbon-Sulfur Composite Cathodes for Sulfur Batteries
Authors: Arie Arenst Andreas , Prijadi Alexander Willliam
Published: July 2022

Nano porous carbon and sulfur composites were prepared using microalgae as carbon precorsors by the melt diffusion method. Initially, nano porous carbon materials were synthesized by the hydrothermal method, followed by the chemical activation method with and without ferrocene as catalyst. Therefore, we have two types of porous carbon samples, the first sample was denoted as NPC (preparation with ferrocene) and the other one is PC (preparation without ferrocene) Brunauer–Emmett–Teller analysis indicated that the surface area and total pore volume (at P/P
o) of NPC samples were lower than those of the PC samples. The NPC and PC samples were then mixed with sulfur to obtain NPC-S and PC-S composites. Those composites were then utilized as cathode materials for Lithium Sulfur Battery. The NPC-S samples with a sulfur content of 76.7 wt.% exhibited a higher initial specific capacity and better cycle retention than those of the PC-S. Optimized sulfur content for NPC-S was investigated to handle the shuttle effect problem. improved electrochemical performance is attributed to the increased conductivity of the NPC-S samples and optimized sulfur loading content, which effectively confined lithium polysulfide intermediates.
Li Host Carbon Materials As the Negative Electrode for a Li-Metal Battery – Mechanistic and Practical Assessment
Authors: Zhou Bingxin , Fang Baizeng , Stosevski Ivan , Bonakdarpour Arman , Wilkinson David P.
Published: July 2022

The lithium metal anode is highly valued in the development of high-energy density storage devices owing to its high specific capacity. However, the growth of lithium dendrites and high-volume expansion during the charging process creates significant issues for commercial application. To regulate the lithium deposition behavior various methods have been proposed among which carbon-based materials are being widely investigated because of their unique advantages including high conductivity, along with the material availability and ease of operation. However, current literature on lithium deposition in carbonaceous hosts have contradictory conclusions and further investigation is needed1–4.

Herein, pure hollow core-carbon spheres (PHCCSs), deposited on copper foil (PHCCS@Cu), are used to study the lithium deposition behavior with respect to this type of structure. It is demonstrated that lithium shows some initial and limited intercalation into the PHCCSs and then plates on its external walls and the top-surface of the hollow core carbon structures during the charging process. Figure 1 shows initial lithium insertion followed by lithium deposition with a greater amount of charging. A possible mechanism of lithium deposition inside the PHCCSs is discussed from the aspect of lithium-ion transport and lithium deposition site preference. The application potential of PHCCSs from the point of view of lithium metal volumetric capacity (VC) are also discussed.

References

G. Zheng et al., Nat. Nanotechnol., 9, 618–623 (2014) http://dx.doi.org/10.1038/nnano.2014.152.

D. Lin et al., Nat. Nanotechnol., 11 (2016).

K. Yan et al., Nat. Energy, 1, 16010 (2016).

W. Ye et al., Adv. Energy Mater., 10, 1–10 (2020).

Figure 1
(Invited) Utilization of Single Walled Carbon Nanotube Sensors to Quantify Extracellular Nitric Oxide Concentrations Released By Cells
Authors: Acosta Ramirez Ivon , Conover Carley , Kolar Karleen , Iverson Nicole M
Published: July 2022

Nitric Oxide (NO) is an essential component in cell signaling, but its concentration and mechanisms of action during healthy and diseased states is largely unknown. Researchers have tried to quantify NO for years, but the lack of a sensor that can detect NO, not an upstream or downstream indicator of NO’s presence, in a spatial format has hindered their ability. Through the use of single walled carbon nanotube sensors that are adhered to a sterile platform, the extracellular concentration of NO can be quantified in a spatial-temporal manner. Mapping the concentration of NO for different cell types as they perform different functions, specifically proliferation and migration, will allow for a greater understanding of cell function and the development of more effective treatments of diseased cells in the future.
Organic Color Center-based Optical Nanosensors to Monitor Lysosomal Activity
Authors: Randall Ewelina , Heller Daniel A. , Kim Mijin
Published: July 2022

Semiconducting single-walled carbon nanotubes (SWCNTs) have been investigated as a promising intracellular and in vivo imaging probe due to their high photostability and near-infrared fluorescence. The conjugation of covalent sp3 defects on SWCNTs, organic color centers (OCC), enables a newly developing category of biosensors with their unique sensitivities and increased quantum yield. In this presentation, we show the development of an OCC-based optical nanosensor that is capable of quantitive and temporal measurement of lysosome activities in live cells and solid tumors in live mice. We report the optimization of the OCC-based nanosensor to improve biocompatibility, colloidal stability, and functionality for biomedical applications. We believe that the discovery of OCC sensitivities and new methods to control the SWCNT surface chemistry will lead to the development of novel biosensors and facilitate the understanding of the regulatory mechanisms of dysregulated biological systems in disease.