Effect of Poly-TPD: P3HT Blend on OFETs Performance and NO₂ Gas-Responsiveness

OFET devices with a single polymer sensitive layer have low responsiveness to NO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> gas. Therefore, the material poly [N,N ‘-bis (4-butylphenyl)-N, N’-bis (phenyl) benzidine] (poly-TPD) and polymer poly (3-hexylthiophen-2, 5-diyl) (P3HT) used as the hole transport layer were blended as the active layer. The electrical properties of the devices were measured by varying the blending ratio, and the gas response of the devices with different blending ratios was measured in NO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> atmosphere. AFM, UV-vis characterization methods were used to analyze the properties of thin films under different blending ratios, and the reasons for the changes in electrical properties of devices with different blending ratios were analyzed. It is found that phase separation occurs in the active layer thin film, and the interface between thin film and gas is increased, which improves the nitrogen dioxide gas responsiveness of OFETs devices.