Micro-scale aerosol jet printing of superparamagnetic Fe3O4 nanoparticle patterns

Abstract

The opportunity to create different patterns of magnetic nanoparticles on surfaces is highly desirable across many technological and biomedical applications. In this paper, this ability is demonstrated for the first time using a computer-controlled aerosol jet printing (AJP) technology. AJP is an emerging digitally driven, non-contact and mask-less printing process which has distinguishing advantages over other patterning technologies as it offers high-resolution and versatile direct-write deposition of a wide range of materials onto a variety of substrates. This research demonstrates the ability of AJP to reliably print large-area, fine-feature patterns of superparamagnetic iron oxide nanoparticles (SPIONs) onto both rigid material (glass) and soft and flexible materials (polydimethylsiloxane (PDMS) films and poly-L-lactic acid (PLLA) nanofilms). Investigation identified and controlled influential process variables which permitted feature sizes in the region of 20 μm to be realised. This method could be employed for a wide range of applications that require a flexible and responsive process that permits high yield and rapid patterning of magnetic material over large areas. As a first proof of concept, we present patterned magnetic nanofilms with enhanced manipulability under external magnetic field gradient control and which are capable of performing complex movements such as rotation and bending, with applicability to soft robotics and biomedical engineering applications.

Aerosol‐Jet Printed Sensors for Environmental, Safety, and Health Monitoring: A Review

“…[ 51 ] It is worth noting that superparamagnetic iron oxide‐based inks (Fe 3 O 4 ) have been recently demonstrated using AJP onto both rigid and flexible platforms to execute movements including rotation, translation, and out‐of‐plane bending, which could potentially benefit various biomedical and soft robotics applications. [ 52 ] Recently, metal hydride‐based materials (e.g., titanium hydrides (TiH 2 )) have also been introduced as AJP inks. Despite their higher resistivity than silver‐ and copper‐based nanoparticle inks, advantages of corrosion resistance, biocompatibility, improved stability, and versatility can be potentially unlocked for their integration to numerous applications.…”

Formulation and Aerosol Jet Printing of Nickel Nanoparticle Ink for High-Temperature Microelectronic Applications and Patterned Graphene Growth

“…Aerosol jet printing (AJP) is an additive manufacturing alternative to traditional subtractive sensor fabrication techniques . Known for its flexibility of design, this computer-aided design (CAD) driven process directly writes nanoparticle inks onto the surface of various substrates including sapphire, piezoelectric materials, and steel . AJP is a low-temperature fabrication technique often used to print onto flexible polymer substrates like Kapton .…”

Spray‐Coated, Magnetically Connectable Free‐Standing Epidermal Electrodes for High Quality Biopotential Recordings

“…Spray-coating has already been used to deposit PEDOT:PSS for the fabrication of thin films and electrodes, [31,32] functionalized fabrics, [33] solar cells, [34] and organic electronics devices, sensors and transistors, [35][36][37] while, recently, an aerosol jet printing technique has been proposed for the patterning of superparamagnetic features, thus confirming the possibility of conveniently depositing magnetite nanoparticles in an efficient way. [38] However, the jet printing technique is not suitable for large-area applications, being more convenient for the development of high-resolution features on small areas. Interestingly, the approach presented in this work is, to our knowledge, the first example of an up-scalable, large area method for the fabrication of free-standing PEDOT:PSS/PVA-based epidermal electrodes that ensure both surface and vertical conductivity and can be contacted from the back-side using magnetic connectors, thanks to a combination of (biocompatible) materials and a low-cost, large-area spray coating layer-by-layer technique, here employed to obtain functional free-standing films (rather than as a method to simply transfer a certain material onto a substrate).…”