Muhammad Zulfiqar

Trimetallic PtCoFe Alloy Monolayer Superlattices as Bifunctional Oxygen‐Reduction and Ethanol‐Oxidation Electrocatalysts

A synthesis strategy for the preparation of trimetallic PtCoFe alloy nanoparticle superlattices is reported. Trimetallic PtCoFe alloy monolayer array of nanoparticle superlattices with a large density of high index facets and platinum-rich surface are successfully prepared by coreduction of metal precursors in formamide solvent. The concentration of cetyl trimethyl ammonium bromide plays a vital role for the formation of a monolayer array of nanoparticle superlattices, while the size of nanoparticles is determined by NaI. The prepared monolayer array of nanoparticle superlattices is the superior catalyst for oxygen reduction reaction as well as for ethanol oxidation owing to their specific structural and compositional characteristics.

Versatile electronic and magnetic properties of chemically doped 2D platinum diselenide monolayers: A first-principles study

First-principles calculations have been performed to study the chemically doped platinum diselenide (PtSe2) monolayers. We examine the stability of different doping sites by calculating the formation energy. The different electronic and magnetic characters originate from hybridization between the dopants and nearest local atoms. Exceptional electronic and magnetic characters are observed in the B-, P-, Li-, and Ca-doped cases because of doping site independence. The magnetic behavior of the dopant atoms is found to be complex because of interplay between strong structural relaxation, spin lattice coupling, and crystal field splitting. More interestingly, the ferromagnetic half metallic character obtained in B- and N-doped cases, expected to be very useful because of large half metallic energy bandgap. The interaction between dopants is analyzed as a function of their separation, showing that substitution typically counteracts spin polarization. The long range ferromagnetic behavior can be established with...

Magnetic properties of X-C2N (X=Cl, Br and I) monolayers: A first-principles study

The electronic and magnetic properties of X-C2N (X=F, Cl, Br and I) monolayers have been systematically investigated from first-principles calculations. The F atom can be strongly adsorbed on the top of the host carbon atoms, while the Cl, Br and I atoms favor the top of the host nitrogen atoms of C2N monolayers. These functionalized X-C2N (X=F, Cl, Br and I) monolayers exhibit interesting electronic and magnetic features. The F-C2N monolayer system shows a nonmagnetic metallic state, while the X-C2N (X=Cl, Br and I) monolayer systems exhibit the magnetic semiconducting ground state. Moreover, the ferromagnetic state is energetically more stable configuration for the X-C2N (X=Cl, Br and I) monolayer systems. Magnetic analysis further elaborates that the induced magnetism in the X-C2N (X=Cl, Br and I) monolayer systems mainly arises from the local magnetic moments of the halogen adatoms. Thus, the chemical functionalization of nitrogenated honey graphene through halogen atoms adsorption has promising applications in electronic devices.