Synthesis of flower-like BaTiO3/Fe3O4 hierarchically structured particles and their electrorheological and magnetic properties

Abstract

Flower-like BaTiO3/Fe3O4 hierarchically structured particles composed of nano-scale structures on micro-scale materials were synthesized by a simple solvothermal approach and characterized by the means of X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), magnetic testing and rotary viscometer. The influences on the morphology and structure of solvothermal times, type and amount of surfactant, EG : H2O ratio, etc. were studied. Magnetic testing results show that the samples have strong magnetism and they exhibit superparamagnetic behavior, as evidenced by no coercivity and the remanence at room temperature, due to their very small sizes, observed on the M-H loop. The saturation magnetization (M(s)) value can achieve 18.3 emu g(-1). The electrorheological (ER) effect was investigated using a suspension of the flower-like BaTiO3/Fe3O4 hierarchically structured particles dispersed in silicone oil. We can observe a slight shear-thinning behavior of shear viscosity at a low shear rate region even at zero applied electric field and a Newtonian fluid behavior at high shear rate regions.

Fabrication of polyaniline coated iron oxide hybrid particles and their dual stimuli-response under electric and magnetic fields

“…Furthermore, due to their oxidation state these magnetic particles are not easily affected by the corrosion under acidic conditions compared to the CI particles [12]. Concurrently, as an electroresponsive material, polyaniline (PANI), has been investigated extensively in ER systems [13][14][15] because of its easy synthesis, good thermal stability, low cost, and reversible doping/dedoping process to control the conductivity. Both ER and MR fluids have been studied extensively but there are only a few reports on electrorheological/magnetorheological (EMR) suspensions.…”

Conducting polyaniline-wrapped sepiolite composite and its stimuli-response under applied electric fields

“…Electrorheological (ER) fluids, which solidify under applied electric fields in the order of kV/mm, are suspensions of polarizable particles dispersed in a non-conducting liquid [1][2][3][4][5]. Under an applied electric field, these polarized particles behave as electric dipoles that link with each other to form chains, exhibiting a rapid (in the order of milliseconds) phase transition from a fluid-like state to a solid like state in the direction of the applied electric field [6][7][8].…”

Graphene-induced tiny flowers of organometallic polymers with ultrathin petals for hydrogen peroxide sensing

“…Synthesis of inorganic flowers including metals and metal oxides has been extensively explored through electrodeposition and wet chemistry approaches [1][2][3][4][5][6][7][8][9]. Recently, polymer flowers exhibiting superb hydrophobicity have also been generated by means of self-assembly of polymers [10,11].…”