Regulation NO and NH₃ Sensing of Organic Transistors via Synergy of Bias-Stress Effect and Photoexcitation

Bias-stress effect causing undesirable charge trapping and performance degradation are considered huge obstacles for high-performance organic transistors. Besides the extra effort to suppress it, it is innovative to use the synergy of bias-stress effect and photoexcitation to pre-regulate traps and effectively regulate the response and selectivity of organic transistor to NO and NH ₃ . The transistor-type chemical sensor with bias-stress instability and photo response was fabricated based on a low-crystallinity polymer semiconductor, indacenodithiophene-benzothiadiazole (IDTBT), and unmodified SiO ₂ dielectric layer. Sensors operated in pre-stressed dark conditions have more hole traps and improve the response to oxidizing NO, which enhanced 2 times than that under light conditions. Under light conditions, the removal of hole traps via photoexcitation facilitates the regeneration of hole trap by reducing NH ₃ , the corresponding response is 1.4 times that of the pre-stressed dark condition.