Subject:
All Disciplines Arts & Humanities Biology & Life Sciences Business & Economics Chemistry & Materials Science Computer Science & Mathematics Engineering Environmental & Earth Sciences Medicine & Pharmacology Physical Sciences Public Health & Healthcare Social Sciences
Sort:
Most Viewed Latest Alphabetical (A-Z) Alphabetical (Z-A)
Filter:
All Topic Review Biography Peer Reviewed Entry Video Entry
Topic Review
MP and MPc
Metalloporphyrins (MP) and metallophtalocyanines (MPc) are innovative materials with catalytic properties that have attracted attention for their application for diverse electrochemical purposes. The presence of metallic centers in their structure offers a redox-active behavior that is being applied in the design of solid electrodes for the quantification of biomolecules, water contaminants, and pharmaceuticals, among others.
  • 1.0K
  • 25 May 2021
Topic Review
The Recent Progress on Silver Nanoparticles
Nanomaterials are highly effective,  environmentally friendly, and applicable for various applications. Recently, silver nanoparticles (Ag NPs) are increasingly being synthesized due to their physical, chemical, and biomedical properties. Silver nanoparticles can be synthesized using physical, chemical, and biological methods. Ag NPs are widely applied in electronic and sensing applications.
  • 1.0K
  • 20 Nov 2021
Topic Review
Antioxidants and Carbon-Based Electrodes
Antioxidants are compounds that prevent or delay the oxidation process, acting at a much smaller concentration, in comparison to that of the preserved substrate. Primary antioxidants act as scavenging or chain breaking antioxidants, delaying initiation or interrupting propagation step. Secondary antioxidants quench singlet oxygen, decompose peroxides in non-radical species, chelate prooxidative metal ions, inhibit oxidative enzymes. Based on antioxidants’ reactivity, four lines of defense have been described: Preventative antioxidants, radical scavengers, repair antioxidants, and antioxidants relying on adaptation mechanisms. Carbon-based electrodes are largely employed in electroanalysis given their special features, that encompass large surface area, high electroconductivity, chemical stability, nanostructuring possibilities, facility of manufacturing at low cost, and easiness of surface modification. Largely employed methods encompass voltammetry, amperometry, biamperometry and potentiometry. Determination of key endogenous and exogenous individual antioxidants, as well as of antioxidant activity and its main contributors relied on unmodified or modified carbon electrodes, whose analytical parameters are detailed. Recent advances based on modifications with carbon-nanotubes or the use of hybrid nanocomposite materials are described. Large effective surface area, increased mass transport, electrocatalytical effects, improved sensitivity, and low detection limits in the nanomolar range were reported, with applications validated in complex media such as foodstuffs and biological samples.
  • 1.0K
  • 12 Apr 2021
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.
  • 1.0K
  • 31 Oct 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.
  • 995
  • 02 Nov 2022
Topic Review
Carbon-LiFePO4 Cathodes for Lithium-Ion Batteries
Li-ion batteries are in demand due to technological advancements in the electronics industry; thus, expanding the battery supply chain and improving its electrochemical performance is crucial. Carbon materials are used to increase the cyclic stability and specific capacity of cathode materials, which are essential to batteries. LiFePO4 (LFP) cathodes are generally safe and have a long cycle life. However, the common LFP cathode has a low inherent conductivity, and adding a carbon nanomaterial significantly influences how well it performs electrochemically.
  • 984
  • 28 Nov 2022
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.
  • 968
  • 24 Jul 2023
Topic Review
Direct-Hydrocarbon Proton-Conducting SOFCs
Solid oxide fuel cells (SOFCs) are promising and rugged solid-state power sources that can directly and electrochemically convert the chemical energy into electric power. Direct-hydrocarbon SOFCs eliminate the external reformers; thus, the system is significantly simplified and the capital cost is reduced. To reduce operating temperatures of SOFCs, intermediate-temperature proton-conducting SOFCs (P-SOFCs) are being developed as alternatives, which give rise to superior power densities, coking and sulfur tolerance, and durability. Due to these advances, there are growing efforts to implement proton-conducting oxides to improve durability of direct-hydrocarbon SOFCs.
  • 958
  • 27 May 2021
Topic Review
MXenes as Electrode Materials for Supercapacitors
MXenes have been considered to be potential building blocks for composites for use in energy storage applications due to their distinctive 2D wafer structure and superior electrical conductivity. MXenes have been combined with multiple active ingredients, including metal oxides and conductive polymers, to produce a synergistic effect. The synthesis method of MXene shows various surface termini and topographies with different energy storage properties, and there have been multiple studies examining surface modification, stoichiometric ratio, and electrode composition control.
  • 955
  • 09 Mar 2023
Topic Review
Scanning Electrochemical Microscopy Applied to Metals and Coatings
Scanning electrochemical microscopy (SECM) is a scanning probe microscope (SPM) technique based on electrochemical principles that allows chemical imaging of materials with spatial resolution. The movement of a microelectrode (ME) in close proximity to the interface allows the application of various experimental procedures that can be classified into amperometric and potentiometric operations depending on either sensing faradaic currents or probe potential values due to concentration distributions resulting from the corrosion process, as sketched in. In addition, alternating current signals can be applied to the ME, leading to AC-operation modes.
  • 945
  • 23 May 2022
Topic Review
Electrolysis of Industrial Wastewater
Water electrolysis is a powerful technology for producing high-purity H2, with negligible emission of greenhouse gases and compatibility with renewable energy sources. Additionally, the electrolysis of organic compounds, such as lignin, is a promising method for localised H2 production, as it requires lower cell voltages than conventional water electrolysis. Industrial wastewater can be employed in those organic electrolysis systems due to their high organic content, decreasing industrial pollution through wastewater disposal. Electrocoagulation, indirect electrochemical oxidation, anodic oxidation, and electro-Fenton are effective electrochemical methods for treating industrial wastewater.
  • 944
  • 27 Apr 2023
Topic Review
Electrochemical Energy Storage Devices
Among electrochemical energy storage (EES) technologies, rechargeable batteries (RBs) and supercapacitors (SCs) are the two most desired candidates for powering a range of electrical and electronic devices. The RB operates on Faradaic processes, whereas the underlying mechanisms of SCs vary, as non-Faradaic in electrical double-layer capacitors (EDLCs), Faradaic at the surface of the electrodes in pseudo-capacitors (PCs), and a combination of both non-Faradaic and Faradaic in hybrid supercapacitors (HSCs). EDLCs offer high power density but low energy density. HSCs take advantage of the Faradaic process without compromising their capacitive nature. Unlike batteries, supercapacitors provide high power density and numerous charge–discharge cycles; however, their energy density lags that of batteries. Supercapatteries, a generic term that refers to hybrid EES devices that combine the merits of EDLCs and RBs, have emerged, bridging the gap between SCs and RBs. 
  • 936
  • 16 Jan 2024
Topic Review
Electroreduction of CO2 toward High Current Density
Carbon dioxide (CO2) electroreduction offers an attractive pathway for converting CO2 to valuable fuels and chemicals. Despite the existence of some excellent electrocatalysts with superior selectivity for specific products, these reactions are conducted at low current densities ranging from several mA cm−2 to tens of mA cm−2, which are far from commercially desirable values. To extend the applications of CO2 electroreduction technology to an industrial scale, long-term operations under high current densities (over 200 mA cm−2) are desirable.
  • 928
  • 05 May 2022
Topic Review
Selenium-Based Cathode Materials for Lithium Batteries
Selenium (Se)-based cathode materials have garnered considerable interest for lithium-ion batteries due to their numerous advantages, including low cost, high volumetric capacity (3268 mAh cm−3), high density (4.82 g cm−3), ability to be cycled to high voltage (4.2 V) without failure, and environmental friendliness. However, they have low electrical conductivity, low coulombic efficiency, and polyselenide solubility in electrolytes (shuttle effect). These factors have an adverse effect on the electrochemical performance of Li-Se batteries, rendering them unsuitable for real-world use.
  • 924
  • 09 Jun 2022
Topic Review
The Gel-State Electrolytes in Zinc-Ion Batteries
Zinc-ion batteries (ZIBs) are receiving increasing research attention due to their high energy density, resource abundance, low-cost, intrinsic high-safety properties, and the appropriate plating/stripping voltage. Gel-state electrolytes possess merits of having a wide electrochemical window, good flexibility, superior water retainability, and excellent compatibility with aqueous electrolytes, which makes them potential candidates for flexible batteries. However, the practical applications of ZIBs with gel-state electrolytes still have some issues of water content easily dropping, poor mechanical stability, and the interface problem. 
  • 924
  • 08 Dec 2022
Topic Review
The Rheological Phase Reaction Method
The term “rheology” stands for the study of a material’s flow behavior under applied deformation forces or stress. The Rheological Phase Reaction (RPR) method is considered a “pollution-less method” to prepare any metal oxides with high crystallinity, phase purity, and fewer agglomerations depending on the proper raw materials and the right temperature conditions are being chosen. 
  • 911
  • 03 Feb 2023
Topic Review
Graphene-Based Cathode Materials for Lithium-Ion Capacitors
Lithium-ion capacitors (LICs) are attracting increasing attention because of their potential to bridge the electrochemical performance gap between batteries and supercapacitors. LICs are still impeded by their inferior energy density, which is mainly due to the low capacity of the cathode. Graphene-based nanomaterials have been recognized as one of the most promising cathodes for LICs due to their unique properties, and exciting progress has been achieved. 
  • 897
  • 13 Dec 2021
Topic Review
Fundamentals of Organic Anode Materials
Redox-active organic anode materials are endowed with obvious advantages, such as low cost, structural diversity, environmental friendliness, outstanding flexibility in their molecular design, low weight, and higher theoretical capacity, which can meet the rising demand for the energy density of next-generation battery systems. In contrast to inorganic compounds, organic materials are mainly composed of such chemical elements that are widely distributed in nature (e.g., C, H, O, N, S). 
  • 893
  • 18 Jan 2023
Topic Review
Electric Double Layer Structure
The electric double layer (EDL) is the most important electrochemical and heterogeneous catalysis region. Because of it, its modeling and investigation are something that can be found in the literature for a long time. However, it is still something in debate, since nowadays a series of new techniques are available for the investigation of this interfacial area at the molecular level by experiments and simulations.
  • 879
  • 09 Dec 2022
Topic Review
Electrolyte Solvation Structure for Aqueous Zinc Ion Batteries
Zinc as an anode, with low potential (−0.762 V vs. SHE) and high theoretical capacity (820 mAh g−1 or 5854 mAh L−1), shows great promise for energy storage devices. The aqueous zinc ion battery (ZIB) is known as a prospective candidate for large-scale application in the future due to its high safety, environmental friendliness, abundant zinc resources on earth, and low-cost advantages. However, the existence of zinc dendrites and side reactions limit the practical application of ZIBs. Therefore, a lot of effort has been made to improve the performance from aspects including the structure design and surface modification of zinc anodes, regulation of the electrolyte solvation structure, and design of the functional separator.
  • 876
  • 09 Feb 2023
  • Page
  • of
  • 9
Featured Entry Collections
>>

Featured Books

>>
Encyclopedia of Social Sciences
Encyclopedia of COVID-19
Encyclopedia of Fungi
Encyclopedia of Digital Society, Industry 5.0 and Smart City
ScholarVision Creations
Feedback