Palladium nanoparticles (NPs) are decorated on the surface of an amine-functionalized graphene oxide (Pd@APGO) and characterized by using various analytical techniques. In this methodology, the surface of graphene oxide is modified using the amine functional groups which help stabilization and distribution of Pd NPs very well and increases the surface electron density of NPs by electron donating from amine groups. This developed catalyst shows a high catalytic activity toward the Suzuki coupling and carbonylative Suzuki–Miyaura coupling reactions at mild reaction conditions. The amine on the graphene oxide plays a very crucial role to stabilize and increase the electron density of Pd NPs and prevents the leaching of Pd metals. The Pd@APGO catalyst showed excellent catalytic activity (>90%) with a large range of substrates for both of the reactions and provides five recycle runs without the loss of its activity.

This work reports oxidative N-dealkylation/carbonylation of tertiary amines to tertiary amides by using molecular oxygen as a sole oxidant using a Pd/C catalyst. This protocol is free from ligands, additives, bases, and cocatalysts. Different tertiary amines as well as aryl iodides have been examined for this transformation, providing desired products in good to excellent yield.

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Novel, simple, stable and reusable silica-supported palladium phosphine complexes were prepared and found to be highly efficient for the carbonylation of unprotected hydroxy, amino, iodoindole and iodopyrazole under optimized conditions.

High-entropy alloys (HEAs) have emerged as a new alloy system, with many attractive properties. Among the fabrication routes, mechanical alloying followed by sintering, have been widely used. However, sintering mechanisms of HEA powders have not yet been fully understood. This work attempts to understand the sintering kinetics of CoCrFeNiMn HEA powders. A comparative study has been done on CoCrFeNiMn alloy powders on as-milled and annealed conditions, which revealed different sintering behaviours. Decreasing densification rates with increasing activation energies were observed through dilatometry after the annealing treatment. Combined diffusion coefficients and activation energies analysed through the sintering models indicate that during sintering of the as-milled powder, mass transport occurred through several modes. On the other hand, the annealed CoCrFeNiMn alloy powder (which was nearly single phase) clearly reveals volume diffusion as the controlling mechanism during sintering. It was characterised with large activation energy.