BaTiO₃nanoparticle-decorated hierarchical Ni nanowire assemblies for magnetoelectric applications

Abstract

One dimensional multiferroic systems with spin-charge coupling at room temperature are highly useful in future multifunctional devices.

Exchange-spring mechanism and Griffiths-like phase in room-temperature magnetoelectric Ni–BaTiO3 composites

“…28 Compared to NP and NW, magnetoelectric composites NP-BTO 1 : 1 and NW-BTO 1 : 1 show an evident decrease of the M S , M R and H C values, which is due to the diamagnetic BTO nanoparticles present in these samples. 21,47 On increasing the wt% of BTO, M S and M R decrease at all temperatures for both NP-BTO and NW-BTO series, as expected. However, in both the series, M-H at all temperatures shows an abnormal trend of H C with an increase in the BTO wt% (see Tables 1 and 2).…”

“…BTO nanoparticles were synthesized through the same procedure as described in our recently published paper. 21 For the present study, the ME composites are prepared using NP and NW as the FM phase and BTO as the FE phase. Two sets of ME composites Ni-BTO in different morphology were synthesized, namely NP-BTO and NW-BTO.…”

“…Ni samples NP and NW have room temperature conductivities of 3.83 Â 10 4 S m À1 and 6.21 Â 10 4 S m À1 , respectively. 21 The high aspect ratio of 1D sample leads to improved conductivity in NW. Hence, the overall conductivity of the NW-BTO composites should also be greater than that of the NP-BTO composites.…”

“…27 Our previous study shows the formation of a Ni(OH) 2 layer at the Ni-BTO interface in BTO decorated Ni nanowires, which represents the bonding of oxygen atoms at the interface. 21 To substantiate the presence of an interfacial NiO layer, we performed XPS analysis (see Hence, the GP in the Ni-BTO ME system is due to the presence of possible short-range FM and AFM clusters in the PM matrix. 65 At low fields, the inverse susceptibility of the GP obeys power law 1/w = (T À T R C ) 1Àl , in which l is the susceptibility exponent (0 r l o 1).…”

“…20 In 2020, we have reported the ME effect in hierarchically grown Ni nanowires decorated with BTO nanoparticles and found that the coercivity gets improved by optimal FE decoration. 21 Recently, our group reported the ME coupling in BTO coated sea urchin-like Ni nanoparticles and found that the ME coupling influences the electric and magnetic transport mechanisms. 81 In several solid-state physical systems, including ferrites 22 and perovskites, 23 Griffiths-like phase (GP) is frequently being reported.…”