Mechanisms of the Accelerated Li+ Conduction in MOF-Based Solid-State Polymer Electrolytes for All-Solid-State Lithium Metal Batteries.

Solid polymer electrolytes (SPEs) for lithium metal batteries have garnered considerable interests owing to their low cost, flexibility, lightweight, and favorable interfacial compatibility with battery electrodes. Their soft mechanical nature compared to solid inorganic electrolytes give them a large advantage to be used in low pressure solid-state lithium metal batteries, which can avoid the cost and weight of the pressure cages. However, the application of SPEs is hindered by their relatively low ionic conductivity. In addressing this limitation, enormous efforts are devoted to the experimental investigation and theoretical calculations/simulation of new polymer classes. Recently, metal-organic frameworks (MOFs) have been shown to be effective in enhancing ion transport in SPEs. However, the mechanisms in enhancing Li+ conductivity have rarely been systematically and comprehensively analyzed. Therefore, this review provides an in-depth summary of the mechanisms of MOF-enhanced Li+ transport in MOF-based solid polymer electrolytes (MSPEs) in terms of polymer, MOF, MOF/polymer interface, and solid electrolyte interface aspects, respectively. Moreover, the understanding of Li+ conduction mechanisms through employing advanced characterization tools, theoretical calculations, and simulations are also reviewed in this review. Finally, the main challenges in developing MSPEs are deeply analyzed and the corresponding future research directions are also proposed.

Longevous Cycling of Rechargeable Zn-Air Battery Enabled by "Raisin-Bread" Cobalt Oxynitride/Porous Carbon Hybrid Electrocatalysts.

Developing commercially viable electrocatalyst lies at the research hotspot of rechargeable Zn-air batteries, but it is still challenging to meet the requirements of energy efficiency and durability in realistic applications. Strategic material design is critical to addressing its drawbacks in terms of sluggish kinetics of oxygen reactions and limited battery lifespan. Herein, a "raisin-bread" architecture is designed for a hybrid catalyst constituting cobalt nitride as the core nanoparticle with thin oxidized coverings, which is further deposited within porous carbon aerogel. Based on synchrotron-based characterizations, this hybrid provides oxygen vacancies and Co-Nx -C sites as the active sites, resulting from a strong coupling between CoOx Ny nanoparticles and 3D conductive carbon scaffolds. Compared to the oxide reference, it performs enhanced stability in harsh electrocatalytic environments, highlighting the benefits of the oxynitride. Furthermore, the 3D conductive scaffolds improve charge/mass transportation and boost durability of these active sites. Density functional theory calculations reveal that the introduced N species into hybrid can synergistically tune the d-band center of cobalt and improve its bifunctional activity. As a result, the obtained air cathode exhibits bifunctional overpotential of 0.65 V and a battery lifetime exceeding 1350 h, which sets a new record for rechargeable Zn-air battery reported so far.

Advanced Material Engineering to Tailor Nucleation and Growth towards Uniform Deposition for Anode-Less Lithium Metal Batteries.

Anode-less lithium metal batteries (ALMBs), whether employing liquid or solid electrolytes, have significant advantages such as lowered costs and increased energy density over lithium metal batteries (LMBs). Among many issues, dendrite growth and non-uniform plating which results in poor coulombic efficiency are the key issues that viciously decrease the longevity of the ALMBs. As a result, lowering the nucleation barrier and facilitating lithium growth towards uniform plating is even more critical in ALMBs. While extensive reviews have focused to describe strategies to achieve high performance in LMBs and ALMBs, this review focuses on strategies designed to directly facilitate nucleation and growth of dendrite-free ALMBs. The review begins with a discussion of the primary components of ALMBs, followed by a brief theoretical analysis of the nucleation and growth mechanism for ALMBs. The review then emphasizes key examples for each strategy in order to highlight the mechanisms and rationale that facilitate lithium plating. By comparing the structure and mechanisms of key materials, the review discusses their benefits and drawbacks. Finally, major trends and key findings are summarized, as well as an outlook on the scientific and economic gaps in ALMBs.

"Tree-Trunk" Design for Flexible Quasi-Solid-State Electrolytes with Hierarchical Ion-Channels Enabling Ultralong-Life Lithium-Metal Batteries.

The construction of robust (quasi)-solid-state electrolyte (SSE) for flexible lithium-metal batteries is desirable but extremely challenging. Herein, a novel, flexible, and robust quasi-solid-state electrolyte (QSSE) with a "tree-trunk" design is reported for ultralong-life lithium-metal batteries (LMBs). An in-situ-grown metal-organic framework (MOF) layer covers the cellulose-based framework to form hierarchical ion-channels, enabling rapid ionic transfer kinetics and excellent durability. A conductivity of 1.36 × 10-3  S cm-1 , a transference number of 0.72, an electrochemical window of 5.26 V, and a good rate performance are achieved. The flexible LMBs fabricated with as-designed QSSEs deliver areal capacity of up to 3.1 mAh cm-2 at the initial cycle with high mass loading of 14.8 mg cm-2 in Li-NCM811 cells and can retain ≈80% capacity retention after 300 cycles. An ultralong-life of 3000 cycles (6000 h) is also achieved in Li-LiFePO4 cells. This work presents a promising route in constructing a flexible QSSE toward ultralong-life LMBs, and also provides a design rationale for material and structure development in the area of energy storage and conversion.

Emerging Trends in Sustainable CO2 -Management Materials.

With the rising level of atmospheric CO2 worsening climate change, a promising global movement toward carbon neutrality is forming. Sustainable CO2 management based on carbon capture and utilization (CCU) has garnered considerable interest due to its critical role in resolving emission-control and energy-supply challenges. Here, a comprehensive review is presented that summarizes the state-of-the-art progress in developing promising materials for sustainable CO2 management in terms of not only capture, catalytic conversion (thermochemistry, electrochemistry, photochemistry, and possible combinations), and direct utilization, but also emerging integrated capture and in situ conversion as well as artificial-intelligence-driven smart material study. In particular, insights that span multiple scopes of material research are offered, ranging from mechanistic comprehension of reactions, rational design and precise manipulation of key materials (e.g., carbon nanomaterials, metal-organic frameworks, covalent organic frameworks, zeolites, ionic liquids), to industrial implementation. This review concludes with a summary and new perspectives, especially from multiple aspects of society, which summarizes major difficulties and future potential for implementing advanced materials and technologies in sustainable CO2 management. This work may serve as a guideline and road map for developing CCU material systems, benefiting both scientists and engineers working in this growing and potentially game-changing area.

Simultaneous electrochemical detection of guanine and adenine using reduced graphene oxide decorated with AuPt nanoclusters.

A rapid and sensitive electrochemical sensing platform is reported based on bimetallic gold-platinum nanoclusters (AuPtNCs) dispersed on reduced graphene oxide (rGO) for the simultaneous detection of guanine and adenine using square wave voltammetry (SWV). The synthesis of AuPtNCs-rGO nanocomposite was achieved by a simultaneous reduction of graphene oxide (GO) and metal ions (Au3+ and Pt4+) in an aqueous solution. The developed AuPtNCs-rGO electrochemical sensor with the optimized 50:50 bimetallic (Au:Pt) nanoclusters exhibited an outstanding electrocatalytic performance towards the simultaneous oxidation of guanine and adenine without the aid of any enzymes or mediators in physiological pH. The electrochemical sensor platform showed low detection limits of 60 nM and 100 nM (S/N = 3) for guanine and adenine, respectively, with high sensitivity and an extensive linear range from 1.0 µM to 0.2 mM for both guanine and adenine. The interference from the most common electrochemically active interferents, including ascorbic acid, uric acid, and dopamine, was almost negligible. The simultaneous sensing of guanine and adenine in denatured Salmon Sperm DNA sample was successfully achieved using the proposed platform, showing that the AuPtNCs-rGO nanocomposite could provide auspicious clinical diagnosis and biomedical applications.

An ultrasensitive electrochemical sensor for the detection of acetaminophen via a three-dimensional hierarchical nanoporous gold wire electrode.

Acetaminophen is one of the most commonly used non-steroidal anti-inflammatory drugs worldwide. However, due to the increasing popularity of this drug, overdosing and the contamination of ambient waterways have emerged as major issues. Here, we report on a reliable, ultrasensitive, and easy-to-use sensor for the electrochemical detection of acetaminophen. This sensor employs a gold wire electrode with a unique three-dimensional hierachical nanoporous structure, fabricated using a dissolution, disproportion and deposition procedure. In consideration of optimal sensitivity and reproducibility, the most suitable nanoporous gold electrode was employed for the detection of acetamiophen among a set of nanoporous electrodes made under different reaction times. It was found that the pore size, film thickness, and electrochemically active surface area (ECSA) played major roles in the fouling resistance of the developed sensor. The ECSA of the selected sensor was increased by 15.8 times after the post-treatment. The 3D nanoporous electrode demonstrated excellent performance for the detection of acetaminophen with a low detection limit of 3.37 nM, and a strong anti-interference capability. The developed nanoporous Au electrode proved effective for the detection of acetaminophen in real sheep serum, which confirmed its promising application for medical diagnostics and pollutant surveilliance in source waters.

Nanomaterial-based electrochemical sensors and biosensors for the detection of pharmaceutical compounds.

The surging growth of the pharmaceutical industry is a result of the rapidly increasing human population, which has inevitably led to new biomedical and environmental issues. Aside from the quality control of pharmaceutical production and drug delivery, there is an urgent need for precise, sensitive, portable, and cost-effective technologies to track patient overdosing and to monitor ambient water sources and wastewater for pharmaceutical pollutants. The development of advanced nanomaterial-based electrochemical sensors and biosensors for the detection of pharmaceutical compounds has garnered immense attention due to their advantages, such as high sensitivity and selectivity, real-time monitoring, and ease of use. This review article surveys state-of-the-art nanomaterials-based electrochemical sensors and biosensors for the detection and quantification of six classes of significant pharmaceutical compounds, including anti-inflammatory, anti-depressant, anti-bacterial, anti-viral, anti-fungal, and anti-cancer drugs. Important factors such as sensor/analyte interactions, design rationale, fabrication, characterization, sensitivity, and selectivity are discussed. Strategies for the development of high-performance electrochemical sensors and biosensors tailored toward specific pharmaceuticals are highlighted to provide readers and scientists with an extensive toolbox for the detection of a wide range of pharmaceuticals. Our aims are two-fold: (i) to inspire readers by further elucidating the properties and functionalities of existing nanomaterials for the detection of pharmaceuticals; and (ii) to provide examples of the potential opportunities that these devices have for the advanced sensing of pharmaceutical compounds toward safeguarding human health and ecosystems on a global scale.

Graphene-Oxide-Based Electrochemical Sensors for the Sensitive Detection of Pharmaceutical Drug Naproxen.

Here we report on a selective and sensitive graphene-oxide-based electrochemical sensor for the detection of naproxen. The effects of doping and oxygen content of various graphene oxide (GO)-based nanomaterials on their respective electrochemical behaviors were investigated and rationalized. The synthesized GO and GO-based nanomaterials were characterized using a field-emission scanning electron microscope, while the associated amounts of the dopant heteroatoms and oxygen were quantified using x-ray photoelectron spectroscopy. The electrochemical behaviors of the GO, fluorine-doped graphene oxide (F-GO), boron-doped partially reduced graphene oxide (B-rGO), nitrogen-doped partially reduced graphene oxide (N-rGO), and thermally reduced graphene oxide (TrGO) were studied and compared via cyclic voltammetry (CV) and differential pulse voltammetry (DPV). It was found that GO exhibited the highest signal for the electrochemical detection of naproxen when compared with the other GO-based nanomaterials explored in the present study. This was primarily due to the presence of the additional oxygen content in the GO, which facilitated the catalytic oxidation of naproxen. The GO-based electrochemical sensor exhibited a wide linear range (10 mM-1 mM), a high sensitivity (0.60 µAµM-1cm-2), high selectivity and a strong anti-interference capacity over potential interfering species that may exist in a biological system for the detection of naproxen. In addition, the proposed GO-based electrochemical sensor was tested using actual pharmaceutical naproxen tablets without pretreatments, further demonstrating excellent sensitivity and selectivity. Moreover, this study provided insights into the participatory catalytic roles of the oxygen functional groups of the GO-based nanomaterials toward the electrochemical oxidation and sensing of naproxen.