New Energy: Science and Technology Articles

Rus

Eng

Synthesis of two-dimensional transition metal carbides and carbonitrides by immersing select MAX phase powders in hydrofluoric acid, HF

The SEM image captured by Babak Anasori shows MXene particles MXenes have potential uses in a broad range of energy and electronics applications, including lithium-ion batteries and supercapacitors. The materials' layered structure resembles that of graphene — hence the suffix ene — a two-dimensional sheet of carbon, but its chemistry is more complex and more versatile.

Researches report on the synthesis of two-dimensional transition metal carbides and carbonitrides by immersing select MAX phase powders in hydrofluoric acid, HF. The MAX phases represent a large (>60 members) family of ternary, layered, machinable transition metal carbides, nitrides, and carbonitrides. Has been present evidence for the exfoliation of the following MAX phases.

Investigation of Carbon Materials for Use as a Flowable Electrode in Electrochemical Flow Capacitors

Schematic of the operation of an EFC system. Slurries are charged in the flow cell Novel electrical energy storage concept, the electrochemical flow capacitor (EFC), holds much promise for grid-scale energy storage applications.

The EFC combines the principles behind the operation of flow batteries and supercapacitors, and enables rapid charging/discharging and decoupled energy/power ratings. Electrical charge is stored in a flowable carbon slurry composed of low-cost and abundantly available carbon particles in pH-neutral, aqueous electrolyte.

MXene - New Family of 2-D Metal Carbides and Nitrides

New energy: Science & Technology Articles

Ti3AlC2 forming two OH-terminated MXene layers An urgent challengecurrently faced by researchers and the public alike is the ability to identify the next generation of sustainable, cost-effective, and energy efficient materials for our everyday use. While searching for new materials for electrical energy storage, a team of Drexel University materials scientists has discovered a new family of two-dimensional compounds proposed to have unique properties that may lead to groundbreaking advances in energy storage technology.

In their paper, the research team recounts their ability to transform three dimensional titanium-aluminum carbide, a typical representative of a family of layered ternary carbides called MAX phases, into a two dimensional structure with greatly different properties. MAX phases, known as ductile and machineable ceramics, have been researched by Prof. Barsoum’s lab for more than a decade and dozens of layered carbides, nitrides and carbonitrides with a variety of properties have been synthesized. However, these ceramics have always been produced as 3-dimensional materials.

Pore Size Reduction Increases Energy Stored In Super Capacitors

Computational modeling of carbon supercapacitors

Yury Gogotsi of Drexel University with his co-workers felt the necessity of studying a potential supercapacitor material at the atomic level to analyze certain experimental results. A research team under the supervision of Oak Ridge National Laboratory’s (ORNL) computational physicist Vincent Meunier and computational chemists Jingsong Huang and Bobby Sumpter enabled the analysis at the atomic level.

When you're talking about nanomaterials, however, that eye is pretty much useless unless it's looking through an electron microscope or at a computer visualization. Yet the pits and ridges on a seemingly flat surface—so small they are invisible without such tools—can give the material astonishing abilities. The trick for researchers interested in taking advantage of these abilities lies in understanding and, eventually, predicting how the microscopic topography of a surface can translate into transformative technologies.

Supercapasitors: Big Energy Storage in Thin Films

Computational modeling of carbon supercapacitors

Energy storage devices called superapacitors can be recharged many more times than batteries, but the total amount of energy they can store is limited. This means that the devices are useful for providing intense bursts of power to supplement batteries but less so for applications that require steady power over a long period, such as running a laptop or an engine.

Now researchers at Drexel University in Philadelphia have demonstrated that it's possible to use techniques borrowed from the chip-making industry to make thin-film carbon ultracapacitors that store three times as much energy by volume as conventional ultracapacitor materials. While that is not as much as batteries, the thin-film ultracapacitors could operate without ever being replaced.

Materials for electrochemical capacitors

Electrochemical capacitors, also called supercapacitors, store energy using either ion adsorption (electrochemical double layer capacitors) or fast surface redox reactions (pseudo-capacitors). They can complement or replace batteries in electrical energy storage and harvesting applications, when high power delivery or uptake is needed. A notable improvement in performance has been achieved through recent advances in understanding charge storage mechanisms and the development of advanced nanostructured materials.

The discovery that ion desolvation occurs in pores smaller than the solvated ions has led to higher capacitance for electroche.