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Topic Review
Battery Specifications
Batteries are the heart and the bottleneck of portable electronic systems. They power electronics and determine the system run time, with the size and volume determining factors in their design and implementation. Understanding the material properties of the battery components—anode, cathode, electrolyte, and separator—and their interaction is necessary to establish selection criteria based on their correlations with the battery metrics: capacity, current density, and cycle life. 
  • 6.4K
  • 07 Sep 2022
Topic Review Peer Reviewed
Reference Electrodes
A reference electrode is a half-cell (an electrode) with a stable, well-defined and highly reproducible electrode potential. A vast number of electrodes have been developed for different applications. They are briefly presented. For the common types, the advantages and drawbacks are discussed. Practical hints for daily use are provided.
  • 3.3K
  • 04 Feb 2024
Topic Review
Application of PEDOT
Poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) is a highly important and attractive conducting polymer as well as commercially available in organic electronics, including electrochemical and electronic chemosensors, due to its unique features such as excellent solution-fabrication capability and miscibility, high and controllable conductivity, excellent chemical and electrochemical stability, good optical transparency and biocompatibility.
  • 2.9K
  • 26 Apr 2021
Topic Review
Li7La3Zr2O12 (LLZO): An Overview
Li7La3Zr2O12 (LLZO) is an inorganic garnet type solid electrolyte which has proven to be one of the most promising electrolytes because of its high ionic conductivity at room temperature, low activation energy, good chemical and electrochemical stability, and wide potential window.
  • 2.9K
  • 03 Aug 2021
Topic Review
Electrode Passivation
The main reason for electrode passivation is adsorption/deposition of a passivating compound on working electrode surface. The most pronounced consequences are the decrease of the rate of electrode reaction resulting in the shift of half-wave or peak potential to more negative (in the case of cathodic reaction) or to more positive (in the case of anodic reaction) potentials and in the decrease of peak current, which is especially in the case of pulsed technique influenced by this rate. 
  • 2.8K
  • 22 Feb 2021
Topic Review
Electrochemical Glucose Sensing
The research field of glucose biosensing has shown remarkable growth and development since the first reported enzyme electrode in 1962. Extensive research on various immobilization methods and the improvement of electron transfer efficiency between the enzyme and the electrode have led to the development of various sensing platforms that have been constantly evolving with the invention of advanced nanostructures and their nano-composites. Examples of such nanomaterials or composites include gold nanoparticles, carbon nanotubes, carbon/graphene quantum dots and chitosan hydrogel composites, all of which have been exploited due to their contributions as components of a biosensor either for improving the immobilization process or for their electrocatalytic activity towards glucose. This review aims to summarize the evolution of the biosensing aspect of these glucose sensors in terms of the various generations and recent trends based on the use of applied nanostructures for glucose detection in the presence and absence of the enzyme.
  • 2.5K
  • 13 Nov 2020
Topic Review
Advances in Electrochemical Glucose Sensing
The detection of glucose is crucial in the management of diabetes and other medical conditions but also crucial in a wide range of industries such as food and beverages. The development of glucose sensors in the past century has allowed diabetic patients to effectively manage their disease and has saved lives. First-generation glucose sensors have considerable limitations in sensitivity and selectivity which has spurred the development of more advanced approaches for both the medical and industrial sectors.
  • 2.5K
  • 21 Jul 2021
Topic Review
The beautiful world of biosensors
The biosensors have important role in science of chemical analysis in the field of electrochemical methods. Their application in rapid detection of toxins in types, we consume in our daily lives, is particularly useful for public health. The main characteristics of evaluation of biosensors is the high sensitivity, high selectivity, the quick response and the reusability. Analysis of the real samples need additionally a method of evaluating the rate of recovery that is the fractional difference of signal between real and simulated samples. The advantages of the use of biosensors are part of the easy construction, portability and low cost. The provision of analytical results of biosensors is similar to that of other far more expensive methods of instrumental chemical analysis.
  • 2.4K
  • 29 Dec 2021
Topic Review
OER Electrocatalysts
The oxygen evolution reaction (OER) is the efficiency-determining half-reaction process of high-demand, electricity-driven water splitting due to its sluggish four-electron transfer reaction. Tremendous effects on developing OER catalysts with high activity and strong acid-tolerance at high oxidation potentials have been made for proton-conducting polymer electrolyte membrane water electrolysis (PEMWE), which is one of the most promising future hydrogen-fuel-generating technologies. Electrochemical water splitting involves two heterogeneous multi-step half-reactions, which are referred to as the cathodic hydrogen evolution reaction (HER) and the anodic oxygen evolution reaction (OER). An important frontier in OER electrocatalysis research is the development of the rational design of catalysts. Most of the excellent OER catalysts with high activity and durability are not stable in acidic solutions. They are easily oxidized and decomposed in a strong acid system, which is one of the indispensable working conditions for PEMWE.  Outstanding OER electrocatalysts should have excellent intrinsic activity and sufficient active sites, and these requirements are generally combined with simplicity and controllability.
  • 2.4K
  • 23 Jun 2021
Topic Review
PEC Reactors for Water/Wastewater Treatment
Now and in the coming years, how we use and treat water, greywater and wastewater will become more important. A suitably designed photoelectrocatalytic (PEC) reactor is one potential solution. The photoexcitation of suitable semiconducting materials in aqueous environments can lead to the production of reactive oxygen species (ROS). ROS can inactivate microorganisms and degrade a range of chemical compounds. In the case of heterogeneous photocatalysis, semiconducting materials may suffer from fast recombination of electron–hole pairs and require post-treatment to separate the photocatalyst when a suspension system is used. To reduce recombination and improve the rate of degradation, an externally applied electrical bias can be used where the semiconducting material is immobilised onto an electrically conducive support and connected to a counter electrode. These electrochemically assisted photocatalytic systems have been termed “photoelectrocatalytic” (PEC). The term is stated in the IUPAC Recommendations 2011 as “electrochemically assisted photocatalysis. The role of the photocatalyst is played by a photoelectrode, often a semiconductor”. A short description of photocatalysis is included as it can be beneficial for those unfamiliar with the topic, before moving onto PEC. This entry is adapted from https://doi.org/10.3390/w13091198
  • 2.3K
  • 20 Oct 2021
Topic Review
Corrosion Cracking in Palladium
Cathodic corrosion is evidenced by the formation of transient complexes of palladium. It is obvious to see a peak of palladium transient by cyclic voltammetry for different amounts of deposited hydrogen expressed as a current during back-diffusion. Therefore, in the part located at the surface of electrolyte, drastic structural changes lead to loss of cohesion and cracking. The objective of this project is to take into account the mechanical constraints formed by diffusion of hydrogen or isotope and the cathodic corrosion produced by formation of superficial hydride transients, both responsible of destruction of palladium or alloyed cathode. To know the origin of these, it was necessary to discriminating the damaging effects encountered.
  • 2.2K
  • 02 Nov 2020
Topic Review
Hydrogen Economy
Environmental issues make the quest for better and cleaner energy sources a priority. Worldwide, researchers and companies are continuously working on this matter, taking one of two approaches: either finding new energy sources or improving the efficiency of existing ones. Hydrogen is a well-known energy carrier due to its high energy content, but a somewhat elusive one for being a gas with low molecular weight. The so-called "Hydrogen Economy" is based on the use of hydrogen as an energy source. This entry examines the current electrolysis processes for obtaining hydrogen, with an emphasis on alkaline water electrolysis.
  • 2.2K
  • 18 Sep 2021
Topic Review
Electrochemical Immunosensor
Electrochemical immunosensors (EI) are systems that combine the analytical power of electrochemical techniques and the high selectivity and specificity of antibodies in a solid phase immunoassay for a target analyte.
  • 2.2K
  • 02 Dec 2021
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.
  • 2.1K
  • 01 Dec 2020
Topic Review
Electrochemical Impedance Spectroscopy
Electrochemical impedance spectroscopy is finding increasing use in electrochemical sensors and biosensors, both in their characterisation, including during successive phases of sensor construction, and in application as a quantitative determination technique.
  • 2.1K
  • 28 Apr 2022
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.
  • 1.8K
  • 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.
  • 1.7K
  • 29 Apr 2021
Topic Review
Ionic Liquids in Electrochemistry
The roles of room temperature ionic liquids (RTILs) and RTIL based solvent systems as proposed alternatives for conventional organic electrolyte solutions are described. Ionic liquids are introduced as well as the relevant properties for their use in electrochemistry (reduction of ohmic losses), such as diffusive molecular motion and ionic conductivity.
  • 1.6K
  • 21 Jan 2021
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.
  • 1.5K
  • 21 Oct 2020
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.
  • 1.5K
  • 09 Oct 2020
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