Study of morphology, magnetic properties, and visible magnetic circular dichroism of Ni nanoparticles synthesized in SiO2by ion implantation

Electroless nickel metallization to prepare SiO2–Ni composite particles via polyelectrolytes route

“…The polyelectrolytesmodified PS beads bearing a negative surface charge were able to attract positively charged, 4-dimethylaminopyridine-coated Au nanoparticles in chemical solutions. Similar electrostatic approach has been used to prepare SiO 2 -Ni composite particles [26,27]. These findings shed lights on using the electrostatic LbL assembly to form metallic nuclei on surface of SiO 2 core preferentially so that the nucleated sites may grow into a continuous metal deposition via the electroless plating.…”

“…Routes to synthesize the composite particles with tailored hierarchical structures include, for example, preferential surface precipitation, seeded growth, Pickering emulsion, electroless (autocatalytic) plating, sonochemistry, and electrostatic layer-by-layer (LbL) assembly [9,10,[13][14][15][16][17][18][19]. Among them, the electroless plating involves use of chemical reducing agent to facilitate reduction of metallic ions in solution so that metallic nuclei can deposit preferentially on the core surface of various chemical compositions, forming either a uniform metal shell or a raspberry core-shell structure so long as a continuous electron transfer between the reacting species can occur selectively at specific activation sites on the core surface [3,9,10,[20][21][22][23][24][25][26][27][28][29][30][31]. The process is facile with a good throwing power, and is also flexible and cost-effective.…”

Plasmonic Nanoparticles in Dielectrics Synthesized by Ion Beams: Optical Properties and Photonic Applications

“…[ 103 ] Recently, a number of literature have been published on the formation of hollow NPs and synthesis of core–shell NPs by one‐ or two‐step ion implantation. [ 104,106–118 ] In addition, specific nuclei‐shell structures such as multilayer NPs can also be synthesized by ion implantation in the simple operating steps. Ren et al performed the fabrication of sandwiched structure of NPs (i.e., Ag shell–nanovoid‐Ag core NPs) by one‐step ion implantation with Ag fluence as high as 2 × 10 17 ions cm −2 , as depicted in Figure .…”

Monitoring superparamagnetic Langevin behavior of individual SrRuO3nanostructures

“…Superparamagnetism has been known for decades [1]; however, the interest in this fundamental phenomenon has increased in recent years in connection with a wider use of spintronic devices consisting of nanoscale magnetic components [2]. Although the best way to study superparamagnetism is by exploring the superparamagnetic behavior of an individual nanoparticle, so far due to technical challenges the study of superparamagnetism has been mainly performed with ensembles of magnetic nanoparticles where the fluctuations are not observed directly but inferred from the field and temperature dependence of the average magnetization of the ensemble [3][4][5][6][7][8].The magnetic fluctuations of an individual superparamagnetic nanoparticle are described in the framework of the Néel-Brown model [9][10][11]. In its simplest form, the model describes a thermally activated process of coherent rotation of a single magnetic domain particle with uniaxial magnetic anisotropy at a temperature T over an energy barrier E b , and it predicts an average waiting time for reversal τ given by τ = τ 0 e E b /kB T , where τ 0 is a sample specific constant linked to Larmor frequency with a typical value on the order of 10 −9 s [12].…”