Inkjet Printing of Magnetic Particles Toward Anisotropic Magnetic Properties

Karam Nashwan Al-Milaji; Ravi L Hadimani; Shalabh Gupta; Vitalij K Pecharsky; Hong Zhao

doi:10.1038/s41598-019-52699-0

Inkjet Printing of Magnetic Particles Toward Anisotropic Magnetic Properties

Sci Rep. 2019 Nov 7;9(1):16261. doi: 10.1038/s41598-019-52699-0.

Authors

Karam Nashwan Al-Milaji¹, Ravi L Hadimani², Shalabh Gupta³, Vitalij K Pecharsky^{3

4}, Hong Zhao⁵

Affiliations

¹ Virginia Commonwealth University, Department of Mechanical and Nuclear Engineering, BioTech One, 800 East Leigh Street, Richmond, VA, 23219, USA.
² Virginia Commonwealth University, Department of Mechanical and Nuclear Engineering, 401 West Main Street, Richmond, VA, 23284, USA.
³ Ames Laboratory of the U.S. Department of Energy, Division of Materials Science and Engineering, Iowa State University, Ames, IA, 50011-2416, USA.
⁴ Department of Materials Science and Engineering, Iowa State University, Ames, IA, 50011-1096, USA.
⁵ Virginia Commonwealth University, Department of Mechanical and Nuclear Engineering, BioTech One, 800 East Leigh Street, Richmond, VA, 23219, USA. hzhao2@vcu.edu.

Abstract

Unique properties of one-dimensional assemblies of particles have attracted great attention during the past decades, particularly with respect to the potential for anisotropic magnetism. Patterned films can be created using inkjet printing; however, drying of particle-laden colloidal droplets on solid surfaces is usually accompanied by the well-known coffee-ring effect, deteriorating both the uniformity and resolution of the printed configurations. This study examines the effect of externally applied magnetic field on particle deposition patterns. Ferromagnetic Gd₅Si₄ particles were formulated in terpineol oil and directly deposited via magnetic field-assisted inkjet printing on a photopaper to generate patterned films with suppressed coffee-ring effect. The particle deposition morphology is determined by both solvent imbibition and particle-magnetic field interactions. Three characteristic times are considered, namely, the critical time for solvent imbibition into the substrate (t_im), the time it takes for particles to form chains in the presence of the magnetic field (t_ch), and the time in which the particles reach the substrate in the direction normal to the substrate (t_pz). The characteristic time ratios (t_pz/t_im) and (t_pz/t_ch) determine the final deposition morphology in the presence of magnetic field. The ability to control particle deposition and assembly, thus tuning the magnetic anisotropic properties of nanostructured materials is a promising approach for many engineering applications.