Rare earth Ce3+ doping regulated the electronic structure and magnetic properties of Ni2P nanoparticles: Experimental and theoretical study

Abstract

Heteroatom doping is a productive strategy to manipulate the properties of nanomaterials. Herein, we for the first time reported the fabrication of homogeneous cerium doped NiP hollow nanoparticles (CeNi)P, (0 ≤ x ≤ 0.05) by thermal decomposition, and investigate cerium doping on the electronic structure and magnetic properties through experimental and theoretical studies. Cerium exists as Ce in the (CeNi)P nanoparticles, which maintain intrinsic hexagonal structure and hollow morphology. Ce preferentially occupies the tetrahedral sites of NiP lattice, leading to enhanced ferromagnetic properties at room temperature. By increasing the content of Ce, the saturation magnetization () values increase first and then decrease. 1 at% Ce doped NiP nanoparticles reaches the highest value of 0.028 emu/g, 7 times larger than undoped NiP. First principles calculations show that Ce doping can improve the metallic properties and induce magnetic ordering in paramagnetic NiP. The magnetic moment mainly originates from the 4 orbital of Ce, and decreases by increasing the doped Ce, which is accordant with the experimental phenomena. Ferromagnetic-antiferromagnetic oscillation occurs in Ce doped NiP, suggesting that the particular ferromagnetic coupling is ascribed to the RKKY interactions between itinerant electrons in metallic NiP host and localized electrons in Ce.