PEDOT:PSS, the highly stretchable and conductive polymer, can enhances the stretchability of Ag NW electrodes when mixed with Ag NW. Because PEDOT:PSS is still connected to the disconnected Ag NWs, the electrode has enhanced stretchability.

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Herein, snake‐skin‐patterned electrodes, with high versatility and excellent biocompatibility, are developed by combining the Kirigami structure and biomimicry. The snake‐skin electrode has excellent stretchability owing to the integration of the Kirigami structure and patterning. The snake skin patterns are optimized through finite element analysis (FEA) simulations to determine the most stretchable pattern structure. Based on the FEA results, we fabricated the optimal pattern on a polyurethane (PU) substrate by sputtering the AgPdCu alloy target. Even at high strains of 30% and 50%, the electrode exhibits much better stretchability compared with the electrode without the snake skin pattern. The best stretchable electrode exhibits a resistance change (ΔR) of less than 1.5 when it is severely stretched at up to 50% strain. Additionally, the dynamic stretching fatigue test, reveals that it exhibits stable conductivity, thus proving the effectiveness of using snake‐skin pattern for stretchable electrodes. The bending, rolling, folding and twisting tests confirm that the electrode has outstanding flexibility, too. A wearable temperature sensor with a snake‐skin‐patterned electrode exhibits stable and highly sensitive temperature sensing properties. In addition, light emitting diodes connected to the stretchable electrode exhibits stable brightness despite severe deformation of the electrodes.

Despite the excellent performance of MXene−Ag nanowire (MA) composite transparent conductive electrodes (TCEs), they rapidly and severely degrade in ambient and humid environments. To address this critical issue, we developed conformal polytetrafluoroethylene (PTFE) passivation thin films prepared using magnetron sputtering at room temperature. Compared to the PTFE passivated electrode, the nonpassivated bare MA-composite electrode exhibited a considerably increased sheet resistance, and the electrode flexibility and electromagnetic interference (EMI) shielding efficiency (SE) degraded rapidly over time because the moisture and impurities severely oxidized the MXene layer in the harsh testing environment. However, the MA-composite electrode with PTFE passivation shows constant sheet resistance, transmittance, flexibility, and EMI SE, even after the 85 °C−85% relative humidity (RH) test. Compared to the nonpassivated MA-electrode-based thin film heaters (TFHs), the PTFE-passivated MA-composite electrode-based TFHs exhibited improved stability and reliability, indicating that the sputtered PTFE film effectively prevented the moisture and impurity penetration of the MA-composite electrodes.

Transparent and flexible polytetrafluoroethylene (PTFE) thin film passivation for ITO/AgPdCu (APC)/ITO (IAI) electrodes is developed to prevent severe degradation and maintain the reliable performance of the flexible IAI electrodes. Also, oxygen ion beam treatment (IBT) on the surface of the IAI electrode improves the adhesion between the top ITO and PTFE passivation layer, as well as the performance of the passivation layer. The IAI electrode with PTFE passivation exhibits constant sheet resistance, transmittance, and flexibility, even after the 85 °C and 85% RH test. However, the bare IAI electrode shows a significant increase in sheet resistance and a decrease in transmittance and flexibility, owing to the incorporation of moisture and impurities into the IAI layer, and agglomeration of the APC layer. To demonstrate the feasibility of PTFE passivation, the performance of flexible and transparent thin film heaters (TFHs) with the bare IAI and PTEF/IAI samples are compared. The better stability and reliability of the PTFE/IAI‐based TFHs than the bare IAI‐based TFHs indicate that the PTFE film effectively prevents the introduction of moisture and impurities. The performance of the TFH with PTFE/IAI electrode implies that sputtered PTFE film is a promising transparent and flexible thin film passivation for high‐quality oxide‐metal‐oxide multilayer electrodes.