Ultrathin, stretchable, and 3D-printable nanotube composites can defend electronics from each electromagnetic interference (EMI) and neutron radiation in excessive environments.
Examine: Ultrathin, Stretchable, and 3D-Printable Complementary Nanotubes–Polymer Composites for Multimodal Radiation Shielding in Excessive Environments. Picture Credit score: Wanut Sawangwong/Shutterstock.com
In a examine revealed in Superior Supplies, researchers mixed single-walled carbon nanotubes (SWCNTs) with boron nitride nanotubes (BNNTs) to create a light-weight shielding system with two complementary roles: SWCNTs suppress electromagnetic interference, whereas BNNTs soak up neutrons.
The group first demonstrated the idea in ultrathin hybrid nanotube movies, then prolonged it right into a stretchable, 3D-printable polymer composite. The work factors to a promising route for shielding supplies in aerospace, nuclear, medical, and protection applied sciences, the place typical safety is usually too heavy or inflexible.
Saving this for later? Obtain a PDF right here.
Digital programs working in house, nuclear services, medical radiation settings, and protection environments face two persistent threats: electromagnetic interference and high-energy neutron radiation. Each can disrupt or injury delicate elements, lowering reliability in situations the place failure could also be pricey or harmful.
Conventional shielding supplies, together with metals and concrete, can present efficient safety, however they’re heavy, rigid, and poorly suited to light-weight or deformable electronics. That has turn out to be a rising drawback as units turn out to be smaller, lighter, and extra adaptable, significantly in versatile electronics and wearable programs.
Two Nanotubes, Two Jobs
The fabric system is constructed round two nanotube varieties with completely different strengths. SWCNTs are electrically conductive and efficient at attenuating electromagnetic waves. BNNTs, in the meantime, comprise boron atoms with a excessive neutron absorption cross-section, making them well-suited to neutron shielding.
Earlier research had largely examined these supplies individually. Right here, the researchers mixed them right into a single multifunctional system designed to deal with each challenges directly.
Creating the Materials
The group first dispersed SWCNTs and BNNTs in answer utilizing surfactants to supply secure suspensions and uniform mixing. Free-standing hybrid movies had been then made by vacuum filtration, yielding buildings usually 10 to twenty µm thick.
Microscopy confirmed a coaxial structure during which SWCNT bundles wrapped round BNNT cores. Raman spectroscopy and Fourier-transform infrared spectroscopy indicated pressure interactions between the 2 nanotube programs, whereas elemental mapping confirmed the distribution of boron, nitrogen and carbon all through the hybrid construction.
To make printable composites, the researchers then integrated the nanotube community right into a polydimethylsiloxane (PDMS) elastomer matrix. The ensuing ink was processed by direct ink writing, an extrusion-based 3D-printing technique that allows layer-by-layer fabrication of complicated geometries. Rheological testing confirmed that the ink had the viscoelastic properties wanted for printing.
Additional measurements, together with conductivity exams, thermogravimetric evaluation, and neutron attenuation experiments, had been used to judge electrical, thermal, and mechanical efficiency.
Examine Outcomes
The hybrid nanotube movies fashioned a dense, interconnected community with sturdy interfacial contact and steady conductive pathways. That construction supported cost transport and underpinned the fabric’s electromagnetic shielding efficiency.
Within the X-band frequency vary, the neat hybrid movies achieved EMI shielding effectiveness above 50 dB at micrometer-scale thicknesses. The shielding was primarily absorption-dominated somewhat than reflection-dominated: vitality was dissipated primarily by ohmic losses in conductive SWCNT pathways, with interfacial polarization taking part in a secondary function.
The examine additionally discovered that percolated SWCNT networks persevered throughout a variety of compositions, serving to protect EMI shielding even when BNNT content material was excessive.
For neutron shielding, a composite with an SWCNT:BNNT ratio of two:8 achieved a neutron attenuation coefficient of about 1.27 mm-1, akin to roughly 72 % attenuation at a thickness of 1 mm. That efficiency was pushed primarily by boron atoms within the BNNT construction.
Skinny Movies and Printable Composites
When the nanotube community was embedded in PDMS, the fabric turned stretchable and printable whereas retaining helpful shielding efficiency. Mechanical exams confirmed fracture strains above 125 %, and EMI shielding remained secure by repeated deformation cycles. Thermal testing confirmed structural stability from cryogenic temperatures close to −196 °C to elevated temperatures round 250 °C.
On this polymer-composite kind, EMI shielding effectiveness reached as much as about 23 dB at sub-millimeter thicknesses. That’s decrease than the efficiency reported for the neat nanotube movies, however nonetheless important for versatile purposes the place printability and mechanical compliance matter.
Structure Additionally Modifications Efficiency
The examine suggests shielding relies upon not solely on composition but additionally construction. Utilizing direct ink writing, the group produced geometrically tunable designs, together with honeycomb lattices. These architectures elevated electromagnetic attenuation by selling a number of inner reflections.
The authors current this as an encouraging early outcome somewhat than a remaining optimisation, nevertheless it reveals how additive manufacturing could possibly be used to tune shielding efficiency by geometry in addition to materials chemistry.
The Larger Image
Taken collectively, the findings define a sensible technique for multifunctional shielding in harsh environments. The neat hybrid movies delivered the strongest mixed EMI and neutron shielding, whereas the 3D-printable PDMS composites provided a extra versatile and application-oriented model of the identical idea.
The broader significance lies in combining low weight, mechanical sturdiness, thermal resilience, and twin shielding in a single platform. That would make the strategy helpful for future digital programs that want dependable safety in demanding working situations.
Journal Reference
Flandy, Kim, Okay., et al. (2026). Ultrathin, Stretchable, and 3D-Printable Nanotubes-Polymer Composites for Multimodal Radiation Shielding in Excessive Environments. Superior Supplies, e13805. DOI: 10.1002/adma.202513805