Biodegradable Metallic Glass for Stretchable Transient Electronics

Abstract

Biodegradable electronics are disposable green devices whose constituents decompose into harmless byproducts, leaving no residual waste and minimally invasive medical implants requiring no removal surgery. Stretchable and flexible form factors are essential in biointegrated electronic applications for conformal integration with soft and expandable skins, tissues, and organs. Here a fully biodegradable MgZnCa metallic glass (MG) film is proposed for intrinsically stretchable electrodes with a high yield limit exploiting the advantages of amorphous phases with no crystalline defects. The irregular dissolution behavior of this amorphous alloy regarding electrical conductivity and morphology is investigated in aqueous solutions with different ion species. The MgZnCa MG nanofilm shows high elastic strain (≈2.6% in the nano-tensile test) and offers enhanced stretchability (≈115% when combined with serpentine geometry). The fatigue resistance in repeatable stretching also improves owing to the wide range of the elastic strain limit. Electronic components including the capacitor, inductor, diode, and transistor using the MgZnCa MG electrode support its integrability to transient electronic devices. The biodegradable triboelectric nanogenerator of MgZnCa MG operates stably over 50 000 cycles and its fatigue resistant applications in mechanical energy harvesting are verified. In vitro cell toxicity and in vivo inflammation tests demonstrate the biocompatibility in biointegrated use.

Advances in Biodegradable Electronic Skin: Material Progress and Recent Applications in Sensing, Robotics, and Human–Machine Interfaces

“…layer in fully biodegradable MgZnCa metallic glass (MG) film for application in intrinsically stretchable electrodes. [262] The PCL is another candidate that can be used in the biodegradable encapsulation of biodegradable magnesium/iron batteries. The use of PCL encapsulation minimized the volume of electrochemical cells and provided higher discharge rates and longer discharge lifetimes.…”

Laser Direct Activation of Polyimide for Selective Electroless Plating of Flexible Conductive Patterns

“…Flexible conductive circuits with special deformability and conductivity are in essential demand for applications in wearable electronic devices, 1−3 medical implants, 4,5 and electromagnetic interference materials. 6,7 To fulfill the requirements of these applications, stable conductivity under various types of deformation or external stress conditions is highly desired, so a stable conductive network on a flexible polymeric insulating material as a substrate is the key.…”

“…Flexible conductive circuits with special deformability and conductivity are in essential demand for applications in wearable electronic devices, − medical implants, , and electromagnetic interference materials. , To fulfill the requirements of these applications, stable conductivity under various types of deformation or external stress conditions is highly desired, so a stable conductive network on a flexible polymeric insulating material as a substrate is the key. Therefore, various techniques, such as inkjet printing, , screen printing, ligand-induced electroless plating, and meniscus-limited electrodeposition, have been investigated in the past for the construction of high-quality flexible conductive circuits.…”

A Composite Microfiber for Biodegradable Stretchable Electronics

“…Recently, stretchable electronic materials that can be integrated seamlessly with deformable, dynamic, and irregular surfaces, particularly on the human body, have presented new opportunities for wearable applications [ 1 , 2 , 3 , 4 , 5 , 6 ]. In addition to stretchable electronics, transient electronics built with biodegradable materials are of increasing interest for future wearable and implantable applications [ 2 , 6 , 7 , 8 , 9 , 10 ].…”

“…Recently, stretchable electronic materials that can be integrated seamlessly with deformable, dynamic, and irregular surfaces, particularly on the human body, have presented new opportunities for wearable applications [ 1 , 2 , 3 , 4 , 5 , 6 ]. In addition to stretchable electronics, transient electronics built with biodegradable materials are of increasing interest for future wearable and implantable applications [ 2 , 6 , 7 , 8 , 9 , 10 ]. Furthermore, a range of biodegradable devices could attain a high level of functionality by introducing stretchability and the thoughtful merging of soft-to-hard materials [ 11 ].…”