Enhanced NO2 gas-sensing performance at room temperature using exfoliated MoS2 nanosheets
材料科学
化学工程
纳米技术
光电子学
工程类
作者
Ho Huu Hau,Truong Tien Hoang Duong,Nguyen Khac Man,Tran Thi Viet Nga,C.T.A. Xuan,Dang Thi Thanh Le,Nguyễn Văn Toàn,Chu Manh Hung,Nguyễn Văn Duy,Nguyễn Văn Hiếu,Nguyễn Đức Hòa
• Simple liquid-phase exfoliated method to fabricate few-layered MoS 2 nanosheets. • Significant NO 2 sensing performance of the sensor based on exfoliated MoS 2 compared to that based on bulk MoS 2 . • The sensor based on the exfoliated MoS 2 nanosheets indicates the highest response of about 8 times to 5 ppm at RT. • The exfoliated MoS 2 nanosheet sensor shows good NO 2 selectivity, ultra-low detection limit, good short- and long-term stability. Gas sensors based on the bulk MoS 2 and exfoliated MoS 2 nanosheets, were fabricated by the probe ultrasonic vibration followed by the drop-casting method. The sensing performance of the sensor based on the exfoliated MoS 2 was much higher than that based on the bulk MoS 2 . The exfoliated MoS 2 sensor showed highest gas response of approximately eight times to 5 ppm NO 2 at room temperature. This fabricated sensor showed a good NO 2 selectivity, ultra-low detection limit, and good short- and long-term stability. Features such as surface-to-volume ratio, sensitive surface, and bandgap vary with the number of material layers of semiconductor two-dimensional transition metal dichalcogenides with superior responsivity at room temperature (RT) and their possible application as flexible electronic devices. Herein, a significant enhancement of NO 2 gas sensing properties of few-layered MoS 2 nanosheets exfoliated from bulk MoS 2 through a simple sonication probe was reported. The gas responses of the sensor based on the exfoliated MoS 2 nanosheets to 0.5–5 ppm NO 2 at RT were as high as 5.3–8 times. At RT, the humidity effect to the performance of the exfoliated MoS 2 sensor was insignificant. The exfoliated MoS 2 sensor also exhibited an ultra-low detection limit of 27 ppb, excellent selectivity, and reliable long-term stability within 8 weeks, which are crucial for future application of the sensor in practical devices. The NO 2 sensing mechanism of the exfoliated MoS 2 nanosheets was discussed in detail.