Publications by authors named "Jeyakumar Karthikeyan"

Designing highly active and robust earth abundant trifunctional electrocatalysts for energy storage and conversion applications remain an enormous challenge. Herein, we report a trifunctional electrocatalyst (CrCo/CoN@CNT-5), synthesized at low calcination temperature (550 °C), which consists of Co-N single atom and CrCo alloy nanoparticles and exhibits outstanding electrocatalytic performance for the hydrogen evolution reaction, oxygen evolution reaction, and oxygen reduction reaction. The catalyst is able to deliver a current density of 10 mA cm in an alkaline electrolytic cell at a very low cell voltage of ∼1.

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Transition metal chalcogenides (TMCs) are a large family of 2D materials that are currently attracting intense interest. TMCs with 3d transition metals provide opportunities for introducing magnetism and strong correlations into the material with manganese standing out as a particularly attractive option due to its large magnetic moment. Here we report on the successful synthesis of monolayer manganese selenide on a NbSe substrate.

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Doping of materials beyond the dopant solubility limit remains a challenge, especially when spatially nonuniform doping is required. In 2D materials with a high surface-to-volume ratio, such as transition metal dichalcogenides, various post-synthesis approaches to doping have been demonstrated, but full control over spatial distribution of dopants remains a challenge. A post-growth doping of single layers of WSe is performed by adding transition metal (TM) atoms in a two-step process, which includes annealing followed by deposition of dopants together with Se or S.

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