Biodegradable Molybdenum/Polybutylene Adipate Terephthalate Conductive Paste for Flexible and Stretchable Transient Electronics

Biodegradable or eco-degradable electronics is an emerging field of technology capable of reducing the excessively increasing electronic waste originating from the rapid development of personalized and bio-integrated devices and skin adhesive patches. Through an advantageous solution process, biodegradable conductive pastes can be employed in various applications of soft and flexible devices. Herein a biodegradable conductive paste composed of molybdenum (Mo) microparticles and polybutylene adipate terephthalate (PBAT) exhibiting excellent mechanical flexibility and stretchability is reported, while also demonstrating substantially superior mechanical and conductive properties compared with previously reported biodegradable polymer matrices such as poly butanedithiol 1,3,5-triallyl-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione pentenoic anhydride (PBTPA) and Candelilla wax (CW) owing to the significant elongation of PBAT. Moderate dissolution in phosphate buffer saline (PBS) accomplishes its full biodegradability and programmable lifecycle. Tetraglycol (TG) enhances elongation and conductivity performance by acting as a lubricant and improving the dispersion of microparticles. The practical implications of the Mo/PBAT pastes are demonstrated in numerous biodegradable electronic applications such as electrodes, strain and temperature sensors, joule heaters, interconnectors, and freestanding radiofrequency (RF) coils.