Chemical synthesis, structure and magnetic properties of Co nanorods decorated with Fe3O4 nanoparticles

Synthetic Approaches to Colloidal Nanocrystal Heterostructures Based on Metal and Metal-Oxide Materials

“…At the relevant heterojunctions, imperfect coincidence of lattice points leads to breaking of the crystal periodicity, giving rise to interfacial strain, which may, in turn, affect the electronic-band alignment [ 34 , 36 ] and electronic coupling between the connected domains [ 310 , 315 , 317 , 318 , 319 ]. The nominal misfit strain may be relaxed via diverse mechanisms, such as: (i) the formation of crystal defects (e.g., dislocations stacking faults) or local deformation of the near-heterointerface lattice (coherency strain), [ 300 , 320 ], both of which are processes allowed at the temperatures at which liquid-phase syntheses are normally conducted; and/or (ii) via graduation in the chemical composition across the heterojunctions, driven by atomic inter-diffusion across the adjoined materials [ 321 , 322 ].…”

“…The nominal misfit strain may be relaxed via diverse mechanisms, such as: (i) the formation of crystal defects (e.g., dislocations stacking faults) or local deformation of the near-heterointerface lattice (coherency strain), [ 300 , 320 ], both of which are processes allowed at the temperatures at which liquid-phase syntheses are normally conducted; and/or (ii) via graduation in the chemical composition across the heterojunctions, driven by atomic inter-diffusion across the adjoined materials [ 321 , 322 ]. Whether alloyed, graded or abrupt interfaces are formed will heavily depend on the specific growth conditions realized [ 300 , 310 , 315 , 316 , 317 , 318 , 319 , 320 , 321 , 322 , 323 ].…”

“…The magnetic behavior may result in being severely altered, with respect to that of their isolated components, even when in the heterostructure magnetic materials are bound to non-magnetic ones [ 267 , 268 , 270 , 275 , 277 , 278 ]. CNHS nanoarchitectures have been demonstrated to hold great potential as functional elements for the engineering of devices for optoelectronics, photocatalysis [ 32 , 36 , 291 ], spintronics and magnetic recording [ 210 , 307 , 308 , 315 , 317 , 318 , 319 ].…”

“…In these ramified nanoheterostructures ( Figure 12 c–f), the FiM-FM exchange coupling that set in between Co and γ-Fe 2 O 3 at the numerous heterointerfaces was manifested into a diversity of exclusive magnetic properties, including noticeable exchange bias, increased saturated magnetization and coercivity, and enhanced thermal stability of the magnetization [ 318 ]. More recently, in the reversed material configuration of Fe 3 O 4 -decorated Co nanorods ( Scheme 4 a, path three), the hard magnetic properties of Co were found to be preserved and dominate the overall magnetic behaviour of the CNHSs [ 319 ].…”

Self-assembled multifunctional Fe3O4 hierarchical microspheres: high-efficiency lithium-ion battery materials and hydrogenation catalysts

“…Moreover, it is wellknown that the precursor transformation method requires two steps, namely the preparation of the precursors and the thermal transition in an inert atmosphere. Furthermore, Fe 3 O 4 MNSs were prepared by a thermal decomposition method from the precursor complexes in high-boiling-point organic solvents at an elevated temperature [13][14][15]. As a beneficial synthetic strategy, the hydro/solvothermal method has been extensively employed in the synthesis of Fe 3 O 4 MNSs [16][17][18][19][20][21][22][23][24].…”