High selective gas sensors based on surface modified polymer transistor.

Gas sensors based on organic field effect transistors have attracted great attentions and achieved much progress because of their inherent merits such as low-cost, room operating temperature, good portability and flexibility. However, high sensitivity and good selectivity are still challenging issues blocking their further development. Herein, we demonstrate a promising strategy for fabricating high selective organic gas sensors through introducing surface modification. Modified substrate with different self-assembling monolayers (SAMs), the sensing properties of polymer OFET gas sensors are varied with terminal group attached on the SAM. The bare device shows significant sensitive to NH 3 , while it becomes much more sensitive to NO 2 if a fluorine substituent SAM adopted. The NH 2 -terminal SAM and CH 3 -terminal SAM bring moderate sensitivity to gases like NH 3 and NO 2. Those various sensitivity and device parameter evolution are promising to generate a patterning recognition for different gases, which may provide a potential promising approach for improving selectivity of organic gas sensors. Image 1 • Polymer transistors with varied performance was achieved based on a series of SAM modification. • Gas sensitivities to several gases ranging from oxidative to reductive are critically dependent on the end group of SAM molecules. • Polymer transistor with F-SAM present a high sensitivity up to 780% to NO 2. • Multiple parameter variations based on the series of devices provide a potential pattern recognition to discriminate gases. [ABSTRACT FROM AUTHOR]