Excellent Conductivity Stability Research Articles

Flexible MWCNT/Silk fibroin film decorated with Pt NPs for electrochemical glucose sensors

Flexible glucose sensor has become a research focus of continuous blood glucose detection methods because it can easily and quickly detect the glucose content in human body fluids. We prepare a multi-walled carbon nanotube (MWCNT)/Silk Fibroin (SF) flexible film, decorated with platinum nanoparticles (Pt NPs) and loaded with glucose oxidase (GOx) to construct a Pt-MWCNT/SF glucose sensor. A flexible conductive film with an electrical conductivity of 8.5 × 10−5 S/m is prepared by controlling the content of MWCNT. The maximum breaking strength and elongation at the break of MWCNT/SF film are 19.12 MPa and 192%. The Pt-MWCNT/SF glucose sensor has excellent conductivity stability under mechanical deformation and accurately detects glucose in the presence of other biomolecules. The linear range of glucose response is 0.1 to 3.75 mM, and the sensitivity is 8.09 μA/mM·cm2. The biological electrode constructed based on MWCNT/SF film has excellent flexibility, which is expected to be integrated with other electronic devices for monitoring and managing human health.

Highly Stretchable Conductor by Self-Assembling and Mechanical Sintering of a 2D Liquid Metal on a 3D Polydopamine-Modified Polyurethane Sponge.

A highly stretchable conductor was fabricated through dip-coating a new liquid metal (LM) electric ink on a polydopamine (PDA)-modified three-dimensional (3D) polyurethane sponge (PUS) followed by mechanical sintering. The LM was first sonicated to nanodroplets to reduce the consumption of LM and then modified by 3-mercaptopropionic acid (LMNPS-MPA) to improve the interfacial adhesion between LM and PUS. The denser and even distribution of LMNPS-MPA self-assembling on PDA-treated PUS (PUS-PDA) was successfully prepared via hydrogen bonding interactions. Mechanical sintering of 3D PUS-PDA coated by a two-dimensional (2D) LM layer was then conducted to obtain a continuous conductive network. Comparing with those of the reported 3D conductors, the resulting PUS-PDA-LM composite conductor shows both high electrical conductivity (478 S cm-1) under a low LM consumption of 10 vol% and excellent conductivity stability with the relative resistance change, ΔR/R0, of 2% at 50% strain under stretching deformation. The as-prepared PUS-PDA-LM composites were then successfully applied as flexible and stretchable light-emitting diode (LED) arrays with excellent conductivity and conductivity stability at different deformations. We believe that the 3D stretchable PUS-PDA-LM conductor has many potential applications in flexible sensors, flexible circuits, rollable displays, etc.