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Topic Review
Metal Nanoclusters
Metal nanoclusters (NCs), comprising only a few to roughly hundreds of metal atoms, have a metal core-protective agent shell structure. Owing to the size of metal NCs approaching the Fermi wavelength of electrons, the spatial confinement of free electrons in metal NCs generates discrete electronic transitions, thereby exhibiting intriguing molecular-like properties. Therefore, metal NCs are deemed to bridge the gap between molecules and nanoparticles.
  • 2.7K
  • 01 Dec 2020
Topic Review
Functional Properties of LSM and LSCF Air Electrodes
An analysis of the literature data on the electrical, thermal, mechanical, and electrochemical properties of the conventional perovskite-type cathode materials shows that lanthanum strontium manganite (La,Sr)MnO3 (LSM) fulfils all the requirements for its use in high-temperature SOFCs. However, as the temperature decreases, the use of LSM materials, which are predominantly electronic conductors with a low level of ionic conductivity, becomes unsatisfactory due to their low electrochemical activity for the oxygen reduction reaction (ORR). On the other hand, cobalt-based perovskite materials, including lanthanum strontium cobaltite ferrite (La,Sr)(Co,Fe)O3−δ (LSCF), are characterized by superior catalytic activity due to high values of both electronic and ionic conductivity.
  • 2.6K
  • 24 Jul 2023
Topic Review
Reconfigurable and Programmable Metamaterials
As an emerging research product in the 21st century, or a new type of artificial composite functional material, metamaterials are subwavelength artificial composite structural materials, whose unit size is generally less than half of the working wavelength.
  • 2.5K
  • 08 Sep 2021
Topic Review
Electrodiffusion in Neuroscience and NPP-Equations
There are two main processes governing the ionic transport, i.e., diffusion—the particle motion caused by a gradient of concentration, and migration—motion of ions caused by a gradient of electrical potential. These two processes are referred to as electrodiffusion. Electrodiffusion of electrolytes serves as a mean for communication in the nervous system. It can directly affect the excitatory transmission in the synaptic cleft. Electrodiffusion maintains the local ions concentration in brain extracellular spaces at heathy levels but may be also involved in the propagation of epileptic seizures during pathological conditions. The accurate interpretation of physiological observations requires better understanding of the underlying electrodiffusion phenomena.The description of electrodiffusion is very often performed using the Nernst–Planck–Poisson (NPP) model. It has been acknowledged that the spatiotemporal dynamics of the ion concentrations in thin dendrites and dendritic spines of nerve cells follow the Nernst–Planck equation, and sub-membrane currents in neuronal membrane have already been successfully described using the NPP model.
  • 2.5K
  • 29 Apr 2021
Topic Review
Electrolysis of BO2− into BH4−
The recycling of sodium borohydride poses a huge challenge to the drive towards a hydrogen economy. Mechano-chemical, thermo-chemical and electrochemical are the only reported methods of recycling sodium metaborate into sodium borohydride. Much attention have been devoted towards the mechano-chemical and thermo-chemical methods of reduction, little focus is devoted to electrochemical methods. This research describes the electrochemical behaviour of borohydride (BH4ˉ) and metaborate (BO2ˉ) anion in alkaline solutions. The electrochemical characteristics of BH4ˉ is controlled by the alkaline concentration, the concentration of the BH4ˉ and the type of electrode material. The attempts to electro-reduce the BO2ˉ into BH4ˉ is reviewed and the challenges, suggestions and future outlook of electro-reduction to recycle the BO2ˉ into BH4ˉ is highlighted.
  • 2.3K
  • 16 Jan 2023
Topic Review
Ion-Selective Electrodes Sensitive to Nitrates Ions
Ion-selective electrodes are a popular analytical tool useful in the analysis of cations and anions in environmental, industrial and clinical samples. 
  • 2.2K
  • 07 Oct 2023
Topic Review
Electroactive Materials Based on TEMPO
The redox-active TEMPO (2,2,6,6-tetramethylpiperidin-1-oxyl-4-yl) fragment is a popular component of organic energy storage and catalytic systems as its benefits include remarkable electrochemical performance and decent physical properties. TEMPO is a verstile compound that finds its use in various chemical and biological systems, and is also known to be an efficient catalyst for alcohol oxidation, oxygen reduction, and various complex organic reactions. It can be attached to various aliphatic and conductive polymers to form energy storage compounds for organic batteries or high-loading catalysis systems. The performance and efficiency of TEMPO-containing materials strongly depend on the molecular structure, and thus rational design of such compounds is vital for successful implementation.
  • 2.2K
  • 28 Apr 2022
Topic Review
Ceramic-Based Hybrid Supercapacitors
Supercapacitors (SCs) have attracted considerable attention among various energy storage devices due to their high specific capacity, high power density, long cycle life, economic efficiency, environmental friendliness, high safety, and fast charge/discharge rates. SCs are devices that can store large amounts of electrical energy and release it quickly, making them ideal for use in a wide range of applications. They are often used in conjunction with batteries to provide a power boost when needed and can also be used as a standalone power source. They can be used in various potential applications, such as portable equipment, smart electronic systems, electric vehicles, and grid energy storage systems.
  • 2.2K
  • 02 Nov 2022
Topic Review
Structure and Reaction Mechanism of Li-CO2 Batteries
A typical type of Li–CO2 battery consists of a porous cathode, electrolyte (liquid, solid), and lithium metal anode.
  • 2.1K
  • 22 Jun 2022
Topic Review
Enhancing Lithium-Manganese Oxide Electrochemical Behavior
Lithium manganese oxide is regarded as a capable cathode material for lithium-ion batteries, but it suffers from relative low conductivity, manganese dissolution in electrolyte and structural distortion from cubic to tetragonal during elevated temperature tests. 
  • 2.1K
  • 27 Apr 2021
Topic Review
Classification of Lindane Based on the Isomeric Form
Hexachlorocyclohexane (HCH) is an artificial organic pollutant also called hexachlorane. It has eight isomeric forms, but of these eight isomeric forms, four α, -β, -γ, and δ-HCHs are the most prevalent. From this compound, γ-HCH (also known as lindane) is the most constant and commonly used compound, and it is the supreme isomer. Lindane is a broad-spectrum chlorinated insecticide that has a mixture of several chemical forms of HCH and is written as γ-Hexachlorocyclohexane or γ-HCH. Organic pollutants are normally pesticides, insecticides, or fertilizer, but HCH is an insecticide that is used on fruits, plants, and animals. Lindane is one of the earliest generations of chlorinated organic insecticides, appearing shortly after the end of World War II. All of the pollutants have the same physical and chemical properties. Therefore, it has also had PBT (Persistent, Bioaccumulative, and Toxic) properties.
  • 2.1K
  • 18 Jul 2022
Topic Review
Graphene
Graphene is the new generation material, which finds potential and practical applications in a vast range of research areas. It has unrivalled characteristics, chiefly in terms of electronic conductivity, mechanical robustness and large surface area, which allow the attainment of outstanding performances in many fields of materials science.
  • 2.1K
  • 09 Oct 2020
Topic Review
Preparation Methods of Titanium Sub-Oxides Electrode
Compared with the instability of graphite electrodes, the high expenditure of noble metal electrodes and boron-doped diamond electrodes, and the hidden dangers of titanium-based metal oxide electrodes, a titanium sub-oxide material has been characterized as an ideal choice of anode material due to its unique crystal and electronic structure, including high conductivity, decent catalytic activity, intense physical and chemical stability, corrosion resistance, low cost, and long service life, etc. 
  • 2.1K
  • 17 Jun 2022
Topic Review
Components of Supercapacitors
The enormous demand for energy due to rapid technological developments pushes mankind to the limits in the exploration of high-performance energy devices. Among the two major energy storage devices (capacitors and batteries), electrochemical capacitors (known as ‘Supercapacitors’) play a crucial role in the storage and supply of conserved energy from various sustainable sources. The high power density and the ultra-high cyclic stability are the attractive characteristics of supercapacitors. However, the low energy density is a major downside of them, which is also responsible for the extensive research in this field to help the charge storage capabilities thrive to their limits. Discoveries of electrical double-layer formation, pseudocapacitive and intercalation-type (battery-type) behaviors drastically improved the electrochemical performances of supercapacitors. The introduction of nanostructured active materials (carbon-/metal-/redox-active-polymer/metal-organic/covalent-organic framework-based electrode materials), electrolytes (conventional aqueous and unconventional systems) with superior electrochemical stability and unprecedented device architectures further boosted their charge storage characteristics. 
  • 2.0K
  • 07 Apr 2023
Topic Review
Lithium-Sulfur Redox Battery
The lithium-sulfur (Li-S) redox battery system is considered to be the most promising next-generation energy storage technology due to its high theoretical specific capacity (1673 mAh/g), high energy density (2600 Wh/kg), low cost, and environmentally friendly nature of sulfur. Though this system is deemed to be the next-generation energy storage device for portable electronics and electric vehicles, its poor cycle life, low coulombic efficiency, and low rate capability limit it from practical applications. These performance barriers were linked to several issues like polysulfide (LiPS) shuttle, inherent low conductivity of charge/discharge end products, and poor redox kinetics. Here, we review the recent developments made to alleviate these problems through an electrocatalysis approach, which is considered to be an effective strategy not only to trap the LiPS but also to accelerate their conversion reactions kinetics. Herein, the influence of different chemical interactions between the LiPS and the catalyst surfaces and their effect on the conversion of liquid LiPS to solid end products are reviewed. Finally, we also discussed the challenges and perspectives for designing cathode architectures to enable high sulfur loading along with the capability to rapidly convert the LiPS.
  • 2.0K
  • 21 Oct 2020
Topic Review
Electrochemical Aptasensors
Over the last few decades, aptamers have attracted a lot of interest in the biosensor industry, because they are the next generation of target receptors that can replace antibody functions. SELEX is an automated procedure and needs only a few days to evolve some binders. This is much shorter compared to antibody selection, which often requires several months. Aptamers can even differentiate the chirality of a molecule and its secondary structure. Aptamers can choose any types of targets with no restrictions. The antibodies undergo permanent degradation, while aptamers can undergo several cycles of denaturation/regeneration. DNA aptamers are acceptable for the design of reusable aptamer detectors, while RNA aptamers can be single-dimensional. The use of aptamers is not limited to specific areas and can be used as recognition molecules in almost any domain. The main limitation is the degradation of RNAs aptamer by ribonuclease. These problems can be solved by modifying RNA aptamers. Another limitation is that the microenvironment will affect the structure of the aptamer and the interactions with the ligand-target. Moreover, the composition of salts has a significant effect on aptamer configuration. The integration of aptamers into detection platforms such as microfluidics and paper-based analytical devices and lab-on-a-chip (LOC) areas for point-of-care (POC) diagnosis is becoming increasingly popular. Aptamer-based detection systems meet most POC diagnostic requirements.
  • 2.0K
  • 28 Sep 2021
Topic Review
Pt-Based Catalysts in Proton Exchange Membrane Fuel Cells
Proton exchange membrane fuel cells (PEMFCs) have attracted extensive attention because of their high efficiency, environmental friendliness, and lack of noise pollution. However, PEMFCs still face many difficulties in practical application, such as insufficient power density, high cost, and poor durability. The main reason for these difficulties is the slow oxygen reduction reaction (ORR) on the cathode due to the insufficient stability and catalytic activity of the catalyst. It is very important to develop advanced platinum (Pt)-based catalysts to realize low Pt loads and long-term operation of membrane electrode assembly (MEA) modules to improve the performance of PEMFC. By designing the structure of a Pt-based catalyst, it can be generated on a special surface structure, so as to boost the stability and activity of Pt-based catalysts, such as low-dimensional nanostructures (e.g., two-dimensional nanoplates and one-dimensional nanowires). These structures not only have high conductivity, but can also make sure the nanocrystals are fully in contact with the support and effectively inhibit Ostwald ripening, with excellent stability.
  • 2.0K
  • 17 Feb 2023
Topic Review
MoS2 Energy Applications
MoS2 is one of the transition metal dichalcogenides (TMDs) that has gained a high reputation in recent years due to its distinct chemical, electronic, mechanical, magnetic, and optical properties. Its unique properties enabled its use in different applications such as sensing applications, high-efficiency field effect transistors, and energy and medical (curing) applications. MoS2 exists in different crystalline structures, such as hexagonal (H), tetrahedral (T), or rhombohedral (R). It naturally exists as 2H MoS2, and its most popular structures are the semiconducting 2H and 3R phases and the 1T metallic phase, where 2H is more stable but less conductive than 1T. Metallic MoS2 has a higher conductivity (105 times) than semiconducting 2H MoS2 and high catalytic activity.
  • 2.0K
  • 16 Sep 2021
Topic Review
High-Capacity Ni-Rich Cathode Materials for Lithium-Ion Batteries
Lithium-ion batteries are undoubtedly known as the most promising rechargeable batteries. Ternary Ni-rich Li[NixCoyMnz]O2 and Li[NixCoyAlz]O2 cathode materials stand as the ideal candidate for a cathode active material to achieve high capacity and energy density, low manufacturing cost, and high operating voltage.
  • 2.0K
  • 19 Feb 2024
Topic Review Video
Physicochemical Processes Leading to Plasma-Driven Solution Electrolysis
A new type of electrolysis, initially known as the contact glow-discharge electrolysis (CGDE) and, more recently, as the plasma-driven solution electrolysis (PDSE), has attracted attention as an alternative method of hydrogen production. PDSE is a nontypical electrochemical process in which electric plasma is formed in the glow discharges excited by the direct or pulsed current in a gas–vapor envelope in the vicinity of the discharge electrode immersed in the electrolytic solution. The yield of chemicals in PDSE (i.e., the ratio of the moles of the product formed to the moles of electrons consumed in a chemical reaction) is several times higher than the Faradaic production of chemicals (predicted by Faraday’s law). In PDSE, new chemical compounds can also be synthesized, which does not happen using Faradaic electrolysis.
  • 2.0K
  • 31 Oct 2022
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