Among many alternatives to fossil fuel-based energy systems, one of the most promising is based on hydrogen and its production use in unitized regenerative fuel cells as primary conversion devices. However, there are some setbacks challenges when designing suitable efficient electrocatalysts for these The effective durable catalysts platinum–group metals, with low abundance unbearably high prices. Many attempts were undertaken overcome this setback by massive commercial use. This review...

Three different metal oxides based on Mn2O3 with TiO2 or NiO were synthesised. Pt PtNi nanoparticles anchored each support, creating a set of nine samples that tested for the oxygen reduction reaction (ORR) and evolution (OER). PtNi/Mn2O3-NiO showed most promising results ORR as evidenced by lowest Tafel slope, highest diffusion-limited current density number electrons exchanged, along stability. The best performance reflects its electrochemical surface area charge-transfer resistance....

Abstract In search for novel materials to replace noble metal‐based electrocatalysts in electrochemical energy conversion and storage devices, special attention is given a distinct class of materials, MAX phase that combines advantages ceramic metallic properties. Herein, Nb 4 AlC 3 prepared by solid‐state mixing reaction characterized morphologically structurally transmission scanning electron microscopy with energy‐dispersive X‐ray spectroscopy, nitrogen‐sorption, diffraction analysis,...

Polyoxometalates (POMs) are polyatomic ions with closed three-dimensional frameworks. Their unique structure contains a large number of redox active sites, making them promising electrocatalysts for electrochemical energy conversion and storage applications. Thus, this paper presents an overview the use POMs as devices, such batteries, supercapacitors, fuel cells, or water electrolyzers. A discussion viability these materials alternatives to noble metal-based is made. The current status...

Pt and Pt-M (M = Ni, Fe, Cu) nanoparticles supported on graphene nanoplatelets (GNPs) were synthesized by simultaneous supercritical carbon dioxide deposition method. Morphology analysis TEM revealed the formation of metal 2–3 nm size uniformly distributed over GNPs, while XPS was used to determine their oxidation states. Four materials tested as electrocatalysts for ORR OER in unitized regenerative fuel cells rechargeable metal-air batteries. PtFe/GNPs exhibited favorable kinetics terms...

A set of platinum (Pt) and earth-abundant transition metals (M = Ni, Fe, Cu) on graphene nanoplatelets (sqPtM/GNPs) was synthesised via sequential deposition to establish parallels between the synthesis method materials' electrochemical properties. sqPtM/GNPs were assessed as bifunctional electrocatalysts for oxygen evolution (OER) reduction (ORR) reactions application in unitised regenerative fuel cells metal-air batteries. sqPtFe/GNPs showed highest catalytic performance with a low...

Bimetallic cobalt (Co)-based coatings were prepared by a facile, fast, and low-cost electroless deposition on copper substrate (CoFe, CoMn, CoMo) characterized scanning electron microscopy with energy dispersive X-ray spectroscopy diffraction analysis. Prepared thoroughly examined for hydrogen evolution reaction (HER) oxygen (OER) in alkaline solution (1 M potassium hydroxide, KOH) their activity compared to that of Co Ni coatings. All five showed both reactions, where CoMo the highest HER...

The basic problem in the operation of automotive brakes is unpredictable nature tribological processes that occur at contact friction pair. stochastic disc brake affected differently by complex interaction between and material under different conditions because influences applied pressure, speed interface temperature. Owing to highly dynamic non-linear change braking torque induced situation brake, could not be modelled, predicted controlled using classical mathematical methods. This...

Developing bifunctional oxygen electrode materials with superior activity for reduction (ORR) and evolution (OER) reactions is essential advancing regenerative fuel cell rechargeable metal–air battery technologies. This present work deals the synthesis characterization of electrocatalysts containing Pt Ni nanoparticles supported on nitrogen-doped mixed metal oxides (Mn2O3-NiO) systematic evaluation their ORR/OER performance in an alkaline medium. These have been successfully synthesized by a...

The new 3D coordination polymer (CP) [Mn(L)(HCOO)]

Molybdenum carbide (Mo2C)-based electrocatalysts were prepared using two different carbon supports, commercial nanotubes (CNTs) and synthesised xerogel (CXG), to be studied from the point of view both capacitive electrocatalytic properties. Cation type (K+ or Na+) in alkaline electrolyte solution did not affect rate formation electrical double layer at a low scan 10 mV s−1. Conversely, mobility these cations through was found crucial for double-layer higher rates. supported on (Mo2C/CXG)...

Gold-silver (AuAg) nanoparticles were deposited on reduced graphene oxide (rGO), with Au wt% varying from 34.6 to 46.2 and Ag ranging 31.7 35.3. Three AuAg/rGO samples characterized by inductively coupled plasma optical emission spectroscopy, transmission scanning electron microscopy energy-dispersive X-ray diffraction analysis. Subsequently, materials studied using the rotating disk electrode as electrocatalysts for oxygen reduction reaction (ORR) potential application in alkaline fuel...

This paper has, for the purpose of setting sustainable cycling mobility, identified and assessed basic risk factors influencing crash severity. The study has examined cyclist injuries fatalities, according to characteristics relative cyclists, roads, vehicles environment posing fatalities or serious injuries. method Binary logistic regression been used as analyze a sample 21,235 traffic crashes involving cyclists in Serbia, over period 2010–2021. task was not define equations prediction, but...

MXenes are the newest class of two-dimensional nanomaterials characterized by large surface area, high conductivity, and hydrophilicity. To further improve their performance for use in energy storage devices, heteroatoms or functional groups can be inserted into Mxenes' structure increasing stability. This work proposes insertion lanthanum atoms niobium-MXene (Nb-MX/La) that was terms morphogy, structure, electrochemical behavior. The addition La to Nb-MXene essential increase spacing...

Pt and Pt-M (M = Ni, Fe, Cu) nanoparticles supported on graphene nanoplatelets (GNPs) were synthesized by simultaneous supercritical carbon dioxide deposition method. Morphology analysis TEM revealed the formation of metal 2-3 nm size uniformly distributed over GNPs, while XPS was used to determine their oxidation states. Four materials tested as electrocatalysts for ORR OER anode reactions in unitized regenerative fuel cells metal-air batteries. PtFe/GNPs exhibited favorable kinetics terms...