Preparation and inhibition behavior of Fe3O4/MBT nanocomposite inhibitor for mild steel in NaCl solution

The hollow Fe 3 O 4 microspheres were firstly synthesized by solvothermal method. And then Fe 3 O 4 /MBT nanocomposite inhibitor was obtained by loading 2-mercaptobenzothiazole (MBT) inhibitor under negative vacuum impregnation treatment and characterized using transmission electron microscopy , X-ray diffraction, Fourier transform infrared spectroscopy , nitrogen adsorption-desorption isotherms and vibrating sample magnetometer . The release behavior of MBT and inhibition behavior of Fe 3 O 4 /MBT nanocomposite under different magnetic field (MF) strength were evaluated by UV–vis spectroscopy, electrochemical techniques and immersion tests. The results show that the synthesized superparamagnetic Fe 3 O 4 /MBT nanocomposite shows high MBT loading capacity of 55.4 %. Under the application of MF, the release behavior of MBT from Fe 3 O 4 /MBT is dominated by Fickian diffusion and diffusion among magnetic nanoparticles , and the release rate and inhibition efficiency are less than that of without MF under the same release time. The nanocomposite has a good inhibition effect for carbon steel in NaCl solution with maximum inhibition efficiency of 95.7 %, and also possesses excellent recycling stability with loading capacity of 45.1 % and inhibition efficiency of 78.8 % after five cycles.