Dynamic Liquid Membrane Electrochemical Modification of Carbon Nanotube Fiber for Electrochemical Microfabrication

Synthesis, surface modifications, and biomedical applications of carbon nanofibers: Electrospun vs vapor-grown carbon nanofibers

Engineered nanostructures are materials with promising properties, enabled by precise design and fabrication, as well as size-dependent effects. Biomedical applications of nanomaterials in disease-specific prevention, diagnosis, treatment, and recovery monitoring require precise, specific, and sophisticated approaches to yield effective and long-lasting favorable outcomes for patients. In this regard, carbon nanofibers (CNFs) have been indentified due to their interesting properties, such as good mechanical strength, high electrical conductivity, and desirable morphological features. Broadly speaking, CNFs can be categorized as vapor-grown carbon nanofibers (VGCNFs) and carbonized CNFs (e.g., electrospun CNFs), which have distinct microstructure, morphologies, and physicochemical properties. In addition to their physicochemical properties, VGCNFs and electrospun CNFs have distinct performances in biomedicine and have their own pros and cons. Indeed, several review papers in the literature have summarized and discussed the different types of CNFs and their performances in the industrial, energy, and composites areas. Crucially however, there is room for a comprehensive review paper dealing with CNFs from a biomedical point of view. The present work therefore, explored various types of CNFs, their fabrication and surface modification methods, and their applications in the different branches of biomedical engineering.

Hydrogen Stabilization and Activation of Dry-Quenched Coke for High-Rate-Performance Lithium-Ion Batteries

Lithium-ion batteries (LIBs) have rapidly come to dominate the market owing to their high power and energy densities. However, several factors have considerably limited their widespread commercial application, including high cost, poor high-rate performance, and complex synthetic conditions. Herein, we use earth-abundant and low-cost dry-quenched coke (DQC) to prepare low-crystalline carbon as anode material for LIBs and tailor the carbon skeleton via a facile green and sustainable hydrogen treatment. In particular, DQC is initially pyrolyzed at 1000 °C, followed by hydrogen treatment at 600 °C to obtain C-1000 H₂-600. The resultant C-1000 H₂-600 possesses abundant active defect sites and oxygen functional groups, endowing it with high-rate capabilities (C-1000 H₂-600 vs. commercial graphite: 223.98 vs. 198.5 mAh g^-1 at 1 A g^-1 with a capacity retention of about 72.79% vs. 58.05%, 196.97 vs. 109.1 mAh g^-1 at 2 A g^-1 for 64.01% vs. 31.91%), and a stable cycling life (205.5 mAh g^-1 for 1000 cycles at 2 A g^-1) for LIBs. This proves that as a simple moderator, hydrogen effectively tailors the microstructure and surface-active sites of carbon materials and transforms low-cost DQC into high-value advanced carbon anodes by a green and sustainable route to improve the lithium storage performance.

Fabrication of a Tool Electrode with Hydrophobic Features and Its Stray-Corrosion Suppression Performance for Micro-electrochemical Machining

Micro-electrochemical machining (micro-ECM) can machine microstructures with excellent surface integrity on difficult-to-cut alloys. During micro-ECM, stray corrosion results in tapered sidewalls of machined structures. To suppress the stray corrosion, a novel tool electrode with the sidewall insulation of a gas film is proposed by fabricating the metal tool sidewall into a hydrophobic surface. The sidewall surface is designed to be characterized with spherical array cavities (radius of 500 nm) acting as the hydrophobic features, enhancing the gas-shielding effect of the gas film under electrolysis. The fabrication process of the hydrophobic sidewall is described in detail, including the self-assembly procedure of a monolayer template of Φ_1 μm polystyrene microspheres, the copper-electroforming procedure for filling the microspheres' gaps, and the removal procedure for forming spherical array cavities. The fabricated tool electrode (Φ_500 μm) obtains the hydrophobic features of a contact angle of up to 138°. As a result, bubbles generated on the tool surface can form an air-electrolyte interface instead of a dispersed bubble cluster. Micro-ECM experiments of microstructures verify that the novel tool electrode can improve machining accuracy by suppressing sidewall stray corrosion.

Dual-heteroatom-templated lanthanoid-inserted heteropolyoxotungstates simultaneously comprising Dawson and Keggin subunits and their composite film applied for electrochemical immunosensing of auximone

Two unprecedented PIII–SbIII-heteroatom templated lanthanide-inserted heteropolyoxotungstates were obtained and their composite film was applied for the electrochemical immunosensing of auximone.