Unique Multifunctionality Research Articles

(Invited) Advancing Carbon Nanotube Synthesis: A Data-Driven Strategy to Overcome Trade-Offs

Materials and their synthesis play pivotal roles in energy storage and conversion. In particular, carbon nanotubes (CNTs) have exhibited potential due to their unique multifunctionality, positioning them as promising elements in this field. However, despite advance in the application of CNTs, challenges persist in both synthesis and processing. The advent of artificial intelligence (AI) has emerged as a transformative tool, empowering researchers and showing promise to expedite scientific breakthroughs. In this presentation, I will briefly discuss our development of a two-stage CNT synthesis process. In addition, I will discuss the application of AI to augment researchers’ capabilities in synthesis and processing. As examples, I will discuss our effort to apply a data-driven approach to attempt to break through synthetic trade-offs in single wall CNT forest growth. I will also discuss our development of a tool to determine dispersants for CNT processing.

Multi-functional amorphous/crystalline interfaces rendering strong-and-ductile nano-metallic-glass/aluminum composite

Metal matrix composites (MMCs) are the materials-of-choice for a large range of important applications under harsh service conditions. However, owing to the high phase contrast between the matrix and the reinforcements, the strength-ductility conflict of MMCs is still outstanding. Here we fabricated a novel aluminum (Al) matrix composite reinforced by deformable, cobalt-zirconium-boron (CoZrB) metallic glass nanoparticles. The amorphous CoZrB/Al composite with only 2.0 vol.% particle reinforcements possessed a uniaxial tensile strength of 387.0 ± 1.2 MPa, showing over 80 % improvement over the unreinforced pure Al matrix at a similar uniform elongation. The strength-ductility synergy of the composite was also significantly superior to that of the composite reinforced by fully crystallized nanoparticles. These findings were rationalized by the unique multi-functionality of the amorphous particle/matrix interfaces, which effectively transferred the load from the matrix to the particles, coordinated the co-deformation of the nanoparticles and the matrix, and imparted a transgranular fracture mode in the composite with extensive matrix plastic deformation. The methodology developed in this study was shown to be generally effective for other matrix and metallic glass nanoparticle compositions, and our work may shed new light on the development of high-performance metal matrix composites for advanced structural applications.

Innovative 3D printing of mechanoluminescent composites: Vat photopolymerization meets machine learning

Mechanoluminescent (ML) materials, which refers to a class of material that emits light upon being subjected to external mechanical stimuli, have been drawing attention due to their unique multifunctionality and potential applications in next-generation structural health monitoring. However, the practical use of ML materials has been limited by the lack of a universally acceptable framework for producing high-intensity ML composites and the challenges in fabricating complex 3D shapes. As a breakthrough, this paper presents a novel approach for producing SrAl2O4:Eu2+, Dy3+ particle-based ML composites using Vat photopolymerization (VP)–based 3D printing, and its process optimization via machine learning-based algorithm. In this study, multi-objective Bayesian optimization (MBO) with Gaussian process regression (GPR) as surrogate model is adopted to fine-tune three critical process parameters in VP process: ML particle content, layer thickness, and cure ratio, aiming for both strong ML properties and reduced printing time. GPR models the complex process input-output relationship, utilizing data collected from experiments. The Pareto-optimal solutions identified by MBO not only enabled the rapid production of high-performance ML specimens but also provided empirical insights into how process parameters affect the end product’s ML property and overall printing time. Furthermore, a micromechanical method for analyzing ML particle volume fraction dependence of the ML intensity is presented to analyze the result. Finally, the practical applicability of the proposed framework was validated by testing ML-based stress sensors and mechanical components using the optimized VP process.

Facile fabrication of functional poly (para-phenylenediamine) nanotubes using self-degraded methyl orange template

Polyaniline (PANI) derivatives, such as poly(phenylenediamine) (para, ortho and meta derivatives) and their nanostructures are attracting immense interest in wide potential applications due to their unique multifunctionality. Here, we report synthesis of polymer nanotubes from poly (para-phenylenediamine) (PpPD) by a simple self-degrading template method using methyl orange (MO) as the structure-directing template and potassium persulfate (KPS) as the oxidant. Two experiment schemes with reversed additions of monomer and oxidant are tested and they demonstrate influence on morphology of the as-produced materials. Electron microscopy and diffraction studies show that the nanotubes with 80 −100 nm outer diameter and more than 1 μm in length, exhibit rectangular cross-section and partial crystallinity. The chemical structures of the material are characterized by EDX, FTIR and UV-Visible spectroscopy. Results show that PpPD nanotubes could be successfully prepared by the facile solution route and demonstrate that the MO template is versatile for preparing nanotubes for not only of conducting polymer but also for its derivative.

Multifunctional Iron Selenate Sheath of Fe-Based Anode Achieving High-Rate Capacity-Durability Combination of Aqueous Hybrid Energy Storage Devices.

The introduction of battery-type cathode has been commonly considered a preferred approach to boost the energy density of aqueous hybrid energy storage devices (AHESDs) in alkalic systems, but AHESDs with both high energy density and power density are rare due to the great challenge in designing battery-type anode materials with high rate and durability comparable to capacitive-type carbon anodes. In this paper, a well-hydrated iron selenate (FeSeO) sheath is constructed around FeOOH nanorods by a facile electrochemical activation, demonstrating the unique multifunction in fasting charge diffusion, promoting the dissociation of H2O, and inhibiting the irreversible phase transition of FeOOH to inert γ-Fe2O3, which endow the hydrated sheath coated Fe-based anodes with an impressive rate capability and superior durability. Thanks to the comprehensive performance of this Fe-based anode, the assembled AHESD delivered a high energy density of 117Whkg-1 with the extraordinary durability of almost 100% capacity retention after 40000 cycles. Even at an ultrahigh power density of 27000Wkg-1, an impressive energy density of 65Whkg-1 can be achieved, which rivals previously reported energy-storage devices.

Molecular Design and Controlled Self-Assembly of Copolymers as Core-Shell-Corona Nanoparticles for Smarter Tumor Treatment.

Copolymer-based core-shell-corona nanoparticles have attracted more interest for tumor chemotherapy, owing to their unique multifunctionality benefiting from their unique multilevel topological structure in comparison with the conventional core-shell ones. Here, the recent progress in such core-shell-corona nanoparticle-based drug delivery systems (DDSs) in tumor chemotherapy was reviewed, focusing on additive functionality of the shell layer for controlled drug release performance from the viewpoints of the molecular design and controlled self-assembly, such as stimuli-responsive gatekeepers, independent loading of active substances, and so on. Moreover, future perspectives have been prospected for smarter tumor treatment.

Conductive and Ferromagnetic Syntactic Foam with Shape Memory and Self‐Healing/Recycling Capabilities

AbstractHerein, a new lightweight syntactic foam is reported with strong mechanical properties, unique multifunctionalities, and recyclability. Multifunctionality of materials and structures has gained ever‐increasing interest as an excellent approach to designing minimalistic systems. Inspired by nature, these materials can perform multiple functions besides bearing a load. Due to their shape‐changing and damage‐healing property, shape memory vitrimers (SMVs) are a great example of multifunctional materials readily exploited for many applications. Using nickel and silver‐plated hollow glass microbubbles (HGMs), an SMV‐based syntactic foam is introduced here that supplements the multifunctionality of SMVs with electrical conductivity and ferromagnetism, which enables a series of additional potentials such as strain sensing, damage monitoring, Joule heating, and electromagnetic interference shielding. Despite its low density and outstanding mechanical properties, this foam exhibits shape memory behavior, which can be triggered by an electrical current, and damage healing capability due to its reversible dynamic covalent bonds. Especially its recyclability makes recycling the expensive silver‐coated and nickel‐coated HGMs feasible, making this foam cost‐effective and environmentally sustainable. With its many features and economical manufacturability, this syntactic foam has a potential to be utilized in many applications, ranging from aerospace structures to biomedical devices to household items.

Recent Advances in the Development and Synthesis of Carbohydrate‐Based Molecules with Promising Antibacterial Activity

AbstractWith the rise of antimicrobial resistance (AMR), innovation in antibacterial drug research and development is urgently needed and strongly encouraged by the World Health Organization (WHO). Carbohydrates are valuable bioactive scaffolds to be explored in this context, and because of their unique multifunctionality, stereochemical diversity, and natural protein‐binding profile, they come across as attractive starting materials for the synthesis of antimicrobial agents with innovative mechanisms of action (MoA). In this concise review, state‐of‐the‐art methodologies for the synthesis of an array of promising and recently developed carbohydrate‐based molecules with antibacterial activity are presented and discussed. By describing successful case studies as platforms for the scrutiny of carbohydrate modification and coupling approaches in organic chemistry, this work summarizes the latest research efforts in this area, ultimately encouraging the design and synthesis of new and much‐needed glycoantibiotic leads for pharmaceutical development.

(Invited) Non-Conventional, Multimodal Strategies to Create Synergistic Effects on Electrode-Electrolyte Interphase Stabilities in Lithium-Ion Batteries

Ni- or Mn-rich cathode materials have attracted great interest for electric vehicle (EV) applications due to their high gravimetric and volumetric energy densities and low- or cobalt-free compositions. For example, Ni-rich LiNi1-xCox/2Mnx/2O2 (NMC) layered cathodes can deliver > 200 mAh/g when they operate at above 4.3 Vvs.Li. Cobalt-free LiNi0.5Mn1.5O4 (LNMO) spinel operates at around 4.75 Vvs.Li and delivers an excellent rate capability due to three-dimensional Li-diffusion pathways in its lattice. However, due to lack of high-voltage stabilities of conventional, carbonate-based electrolytes, such high-voltage operation (> 4.3 Vvs.Li) led to unwanted electrolyte oxidation and simultaneous parasitic reactions occurring at CEI. Different types of cathodes have their own failure mechanisms which are often associated with side reactions occurring at solid-electrolyte interphase (SEI) on graphite anodes. This was possible because the reaction by-products from CEI could migrate and attack SEI layers on anodes.To address the high-voltage related issues, various approaches have been proposed such as tuning chemical compositions of cathode active materials, surface modification of cathodes or anodes, and stabilizing the CEI or SEI using electrolyte additives. In literature, however, there was no single solution that can resolve all the complex issues occurring in the high-voltage battery cells. For example, coated layers on active materials are prone to fail during long-term cycling due to mechanical failure (e.g., crack and pulverization) of active materials. In addition, not only active materials but carbon conductors (e.g., acetylene black) inside a cathode leads to the electrolyte oxidation, prompted by its high electronic conductivity and large surface area. Considering that such parasitic reactions originate from CEI and propagate to anode SEI, there is a dire need of multimodal strategies that can create synergistic effect on stabilizing the electrode-electrolyte interphases in cell level.In this presentation, I will introduce non-conventional strategies that can effectively enhance electrode-electrolyte interphase stabilities and improve full-cell (i.e., using graphite anodes) performances. First, formation of self-healing CEI on cathode active materials will be demonstrated. The interface of LNMO spinel oxide will be passivated by Ti-enriched shell via sacrificial transition metal dissolutions and suppress the side reactions occurring at CEI. Second, a strategy for passivating both cathode active materials and carbon black conductor by using functional binders will be demonstrated. Since the binder coating will be performed in-situ during a slurry preparation, no extra process will be required while implementing this approach to a cell manufacturing. Finally, solid-electrolyte implemented NMC or LNMO cathodes will be demonstrated as an effective approach to stabilize the high-voltage performance by offering good Li-ion conduction pathways at CEI layer.Improvement mechanism of each approach will be also presented based on physical and electrochemical characterization data. Electrochemical impedance spectroscopy (EIS) revealed a suppression of CEI interfacial resistance during cycling, suggesting the enhanced stability of the multifunctional CEI. Various microscopy and spectroscopy data acquired from cycle-aged CEI and graphite SEI will be corelated to the cell performance data and identify the CEI property-performance relationship. These unique multifunction CEI strategies will be applicable to various cathode materials for the next-generation Li-ion batteries. Figure 1

Multifunctional Atomic Molybdenum on Graphene with Distinctive Coordination to Solve Li and S Electrochemistry.

The improvement of lithium-sulfur batteries is still impeded by notorious shuttling effect and sluggish kinetics on theS cathode, and rampant Li dendrite formation on the Li anode makes it worse. Herein, a type of single-atom dispersed Mo on nitrogen-doped graphene (Mo/NG) with a distinctive Mo-N2 O2 -C coordination structure first servingas a multifunctional material is designed by a structure-oriented strategy to solve Li and S electrochemistry. Mo/NG with superior intrinsic properties endowed by the unique coordination configuration adsorbs soluble polysulfides and promotes bidirectional conversion of LiPSs at the cathode side. Meanwhile, the suitable binding strength of Mo/NG with lithium ions endows it with an attractive lithiophilic feature. Specifically, Mo/NG is able to work as the adaptor to redistribute lithium ions on the interface of separator and homogenize the lithium ion flux. Due to the suitable binding ability with Li+ , it does not interfere with the diffusion of lithium ions across and provides tunnels exclusive to lithium ions to generate fast and homogeneous flux. Ascribed to such unique multifunctionality, Li-S batteries assembled with Mo/NG exhibit excellent electrochemical performance including long cycling stability over 1000 cycles and high areal capacities under high sulfur mass loading.

A novel highly osmotic K/Fe3O4/CNF magnetic draw solution for salty water desalination

Forward osmosis (FO) is increasingly being studied as an alternative desalination technique to the other conventional desalination technologies, owing primarily to its low energy potential. However, the co-opted energy limitations in the draw solution (DS) regeneration stage in FO desalination processes and the lack of effective DS have hampered FO's implementation for potable water application on an industrial scale. In this work, we explored the Donnan principle to engineer a DS material having the duality of magnetic and solar-thermal separability functionalities from a sustainability viewpoint whilst exploiting a careful selection of material properties. A novel potassium functionalised iron oxide doped carbon nanofibres (K/Fe3O4/CNF) magnetic nanoparticles (MNPs) was successfully synthesised for FO desalination applications, utilising an eco-friendly strategy that improves hydrophilicity of DS without polymers. The novel DS obtained a significant osmotic pressure (86.1 bar), whilst it FO performance showed a small reverse salt flux (RSF) and specific reverse salt flux (SRSF) values of 0.10 gMH and 0.004 g/L, respectively. These values compare to at least <10 % of most RSF and SRSF values reported in the literature. The facile DS synthesis strategy adopted herein will potentially open a new route to preparing other DS nanomaterials with unique multi functionalities and enhanced hydrophilicity devoid of polymers. Whilst magnetic DS re-concentration may be achievable, additional research is required to appraise this methodology's overall energy implications and economic advantages over existing DS recovery methods.

A Modular Multifunction Power Converter Based on a Multiwinding Flyback Transformer for EV Application

In this article, a revolutionary and novel single-stage, multiport power conversion block is proposed. The power conversion concept is based on a bidirectional flyback converter with four-quadrant switches that permit us to seamlessly control the direction of the energy flow and to select which ports are active. This approach, denominated as multicell multiport bidirectional flyback (M2BF), can be used as a modular and a multifunction building block interfacing ac and dc sources and loads in complex conversion systems like the one we can encounter in electric vehicle (EV) applications. The multiport property is obtained due to the multiwinding flyback transformer that interfaces different sources and loads in a simple and effective way. We present and analyze this concept in detail, focusing on different operation modes it can provide (multiport dc–dc conversion, ac–dc conversion, vehicle-to-grid, grid-to-vehicle, and so on) and their possible implementation in the energy distribution network of an EV, where this unique multifunction multiport converter could bring an important breakthrough. The operating principles of the M2BF for different operating modes are described and analyzed, placing emphasis on the modularity of the proposed concept. The overall concept is evaluated and quantified using a gallium nitride (GaN)-based prototype achieving efficiencies higher than 91% that additionally validates the proposed idea experimentally. The presented analysis and experimental results clearly identify the advantages and limitations of the presented concept leaving no doubt about its usefulness to the future EV distribution network.

Self-assembled vertically aligned nanocomposite systems integrated on silicon substrate: Progress and future perspectives

Silicon (Si) integration is a critical step for implementing functional oxides into Si-based electronic devices, considering the advantages of low-cost and scalability of Si substrates. In the past decade, self-assembled vertically aligned nanocomposites (VANs) have attracted enormous research interest owing to their unique multifunctionalities and highly tunable physical properties as well as their one-step self-assembly process. Most of the VAN thin films have been reported to grow epitaxially on single crystalline oxide substrates, however, with limited systems reported on Si substrates due to the very large lattice mismatch between oxides and Si lattices. In this review, the current progress for self-assembled VAN systems integrated on a Si substrate is summarized. Buffer layered enabled VAN growth has been proven to be an effective approach for improving the epitaxial quality of oxide-oxide and oxide-metal VAN systems, while direct growth is preferred in nitride-metal VAN systems. The material versatility enables the Si-integrated VAN thin films to exhibit distinct physical properties such as ferromagnetism, ferroelectricity, magnetoresistance, as well as unique optical properties. The review also summarizes the various parameters for tuning the growth morphologies and corresponding properties for the VAN systems, including phase molar ratio, deposition frequency, buffer layers, background pressure, etc. Finally, future perspectives are discussed including new VAN system exploration, physical properties tuning, as well as design and fabrication of Si-based nanoelectronics and nanophotonic devices applications.

Review of nanotheranostics for molecular mechanisms underlying psychiatric disorders and commensurate nanotherapeutics for neuropsychiatry: The mind knockout.

Bio-neuronal led psychiatric abnormalities transpired by the loss of neuronal structure and function (neurodegeneration), pro-inflammatory cytokines, microglial dysfunction, altered neurotransmission, toxicants, serotonin deficiency, kynurenine pathway, and excessively produced neurotoxic substances. These uncontrolled happenings in the etiology of psychiatric disorders initiate further changes in neurotransmitter metabolism, pathologic microglial, cell activation, and impaired neuroplasticity. Inflammatory cytokines, the outcome of dysfunctional mitochondria, dysregulation of the immune system, and under stress functions of the brain are leading biochemical factors for depression and anxiety. Nanoscale drug delivery platforms, inexpensive diagnostics using nanomaterials, nano-scale imaging technologies, and ligand-conjugated nanocrystals used for elucidating the molecular mechanisms and foremost cellular communications liable for such disorders are highly capable features to study for efficient diagnosis and therapy of the mental illness. These theranostic tools made up of multifunctional nanomaterials have the potential for effective and accurate diagnosis, imaging of psychiatric disorders, and are at the forefront of leading technologies in nanotheranostics openings field as they can collectively and efficiently target the stimulated territories of the cerebellum (cells and tissues) through molecular-scale interactions with higher bioavailability, and bio-accessibility. Specifically, the nanoplatforms based neurological changes are playing a significant role in the diagnosis of psychiatric disorders and portraying the routes of functional restoration of mental disorders by newer imaging tools at nano-level in all directions. Because of these nanotherapeutic platforms, the molecules of nanomedicine can penetrate the Blood-Brain Barrier with an increased half-life of drug molecules. The discoveries in nanotheranostics and nanotherapeutics inbuilt unique multi-functionalities are providing the best multiplicities of novel nanotherapeutic potentialities with no toxicity concerns at the level of nano range.

Conducting Polyetheretherketone Nanocomposites with an Electrophoretically Deposited Bioactive Coating for Bone Tissue Regeneration and Multimodal Therapeutic Applications.

The use of polyetheretherketone (PEEK) has grown exponentially in the biomedical field in recent decades because of its outstanding biomechanical properties. However, its lack of bioactivity/osteointegration remains an unresolved issue toward its wide use in orthopedic applications. In this work, graphene nanosheets have been incorporated into PEEK to obtain multifunctional nanocomposites. Because of the formation of an electrical percolation network and the π-π* conjugation between graphene and PEEK, the resulting composites have achieved 12 orders of magnitude enhancement in their electrical conductivity and thereby enabled electrophoretic deposition of a bioactive/antibacterial coating consisting of stearyltrimethylammonium chloride-modified hydroxyapatite. The coated composite implant shows significant boosting of bone marrow mesenchymal stem cell proliferation in vitro. In addition, the strong photothermal conversion effect of the graphene nanofillers has enabled laser-induced heating of our nanocomposite implants, where the temperature of the implant can reach 45 °C in 150 s. The unique multifunctionality of the implant has also been demonstrated for photothermal applications such as enhancing bacterial eradication and tumor cell inhibition, as well as bone tissue regeneration in vivo. The results suggest the strong potential of our multifunctional implant in bone repair applications as well as multimodal therapy of challenging bone diseases such as osteosarcoma and osteomyelitis.

Dual-functional ultraviolet photodetector with graphene electrodes on AlGaN/GaN heterostructure

A dual-functional ultraviolet (UV) photodetector with a large UV-to-visible rejection ratio is presented, in which interdigitated finger-type two-dimensional graphene electrodes are introduced to an AlGaN/GaN heterostructure. Two photocurrent generation mechanisms of photovoltaic and photoconductive dominances coexist in the device. The dominance of the mechanisms changes with the induced bias voltage. Below a threshold voltage, the device showed fairly low responsivities but fast response times, as well as a constant photocurrent against the induced bias. However, the opposite characteristics appeared with high bias voltage. Specifically, above the threshold voltage, the device showed high responsivities with additional gain, but slow rise and recovery times. For instance, the responsivity of 10.9 A/W was observed with the gain of 760 at the induced bias voltage of 5 V. This unique multifunctionality enabled by the combination of an AlGaN/GaN heterostructure with graphene electrodes facilitates the development of a single device that can achieve multiple purposes of photodetection.

Perovskite Oxides Tunable by Electromechanical and Electrothermal Couplings

Perovskite oxide thin films is an attractive material group due to their unique multi-functionalities. To broaden the impact of perovskite oxides to practical electronic device applications, their electrical properties will need to be tunable by external means. In this work, we show that electrical conductivity of perovskite STO (SrTiO3) thin films can be largely tuned by mechanical stress (electromechanical coupling) and thermal annealing (electrothermal coupling). The conductive atomic force microscope setup was carefully calibrated to enable precise measurements of electrical response upon application of varying forces, resulting in a high electromechanical coupling sensitivity of up to ~1,000 Sm-1MPa-1. The thermal annealing study also suggests that electrical conductivity of STO is strongly affected by the ambient temperature due to the varying amount of oxygen vacancies.

Microbial exopolysaccharide-based nano-carriers with unique multi-functionalities for biomedical sectors

Herein, we have presented a broad overview of microbial exopolysaccharide (EPS)-based nano-structures that are continuously being explored for their potential biomedical applications, e.g., cell and/or drug encapsulation, gene delivery, tissue engineering, diagnostics, and related therapeutics. The sustainable exploitation of naturally occurring EPS-based polymeric nano-carriers using state-of-the-art nanotech engineering approaches has provided an excellent alternative to conventional bioimaging and drug delivery technologies. EPS-based drug transport covers a specific niche “intelligent therapeutics” which is still being established and has not been well described in the literature. Thus, herein, an effort has been made to cover this literature gap to present unique multi-functional potentialities of microbial EPS with suitable examples. EPS-based nano-pharmaceutics exhibit certain advantages over conventional counterparts, such as ease in preparation, in vivo biocompatibility, biodegradability, and sustainability. EPS and their derivatives are successfully applied for several biomedical applications, e.g., wound dressing scaffolds, arthritis treatment, dental impressions, and tissue engineering purposes. The progress in targeted delivery systems using micro and nanosystems has opened a new dimension in biopolymer-based biomedicines and smart surgical procedures. This huge area of biomedical engineering is described by the availability of a diverse range of EPS-derivatives, whose multi-functional characteristics can be controlled. Through bioconjugation, i.e., functionalized composite production, different systems have been designed, such as controlled drug release and target accumulation of therapeutic substances. Potential EPS applications are not just limited to targeted transport but also covers several emerging diagnostic technologies. Several bioactive EPS have also been studied for their properties like anti-viral, anti-bacterial, anti-tumor and immunomodulatory activities. Based on currently available data on EPS-based nano-structures for biomedical domains, it can be undoubtedly stated that they present a broad future ahead.

Smart multi-layer PVA foam/ CMC mesh dressing with integrated multi-functions for wound management and infection monitoring

In this work, a multi-layer wound dressing consisting of polyvinyl alcohol (PVA) foam and electrospun sodium carboxymethylcellulose (CMC) surface mesh was developed and characterized. Antimicrobial drug stearyl trimethyl ammoium chloride (STAC) was loaded into the PVA foam for infection control and the CMC surface mesh offers effective hemostatic function. Additionally, the potential of laser photodynamic response of the loaded methylene blue (MB) and its effect in enhancing the wound dressing's bacterial inhibition has been investigated. The antibacterial drug and laser photodynamic therapy (PDT) were jointly deployed, which demonstrated greater potential in killing both S. aureus and E. coli bacteria strains. In addition, the unique color changing property of MB has enabled real time bacterial infection monitoring of the wound dressing. The multi-layer wound dressing with ideal material combination and unique multifunctionality may be a promising option for wound management in the future healthcare sector.

Nickel-Salen-Type Polymer as Conducting Agent and Binder for Carbon-Free Cathodes in Lithium-Ion Batteries.

Systematic physical and electrochemical characterizations revealed unique positive multifunction of a polymeric salen-type nickel(II) complex, poly[Ni(CH3-salen)], as an additive for conventional cathodes in lithium-ion batteries. Due to its promising electrochemical and mechanical properties, combined with its unique three-dimensional weblike electron-network structure, the redox-active-organometallic polymer can eliminate conductive carbon and replace a significant portion of the poly(vinylidene fluoride) (PVdF) binder that has been used in conventional LiFePO4 cathodes. By replacing such electrochemically inactive components (i.e., carbon and PVdF), LiFePO4 cathodes with poly[Ni(CH3-salen)] deliver improved energy density compared with the conventional LiFePO4 cathode. Facile electron transfer via large-area contact at polymer/LiFePO4 interfaces significantly accelerates charge-transfer reactions and consequently improves the rate capability of the cathodes. In addition, unlike PVdF, poly[Ni(CH3-salen)] retains steady Young's modulus values after immersing in an electrolyte solvent, which enhances the mechanical integrity of the cathodes during the cycling of battery cells and thereby improves their cycle life. The unique multifunction of the poly[Ni(CH3-salen)] will be of broad interest for its application in next-generation energy-storage devices.