Colloidal quantum dot-based surface acoustic wave sensors for NO2-sensing behavior

SENSORS AND ACTUATORS B-CHEMICAL

卷:287

Article

Li, Min^1,2  Kan, Hao^1,2  Che, Shutian³  Feng, Xiaoying¹  Li, Hui¹  Li, Chong¹  Fu, Chen¹  Quan, Aojie¹  Sun, Huibin¹  Luo, Jingting¹  Liu, Xueli⁴  Wang, Wen⁴  Liu, Huan⁵  Wei, Qiuping⁶  Fu, Yongqing⁷ 

[1] Shenzhen Univ, Coll Phys & Energy, Shenzhen Key Lab Adv Thin Films & Applicat, Shenzhen 518060, Peoples R China

[2] Shenzhen Univ, Key Lab Optoelect Devices & Syst, Minist Educ & Guangdong Prov, Coll Optoelect Engn, Shenzhen 518060, Peoples R China

[3] Nanjing Inst Technol, Sch Mat Sci & Engn, Nanjing 211167, Jiangsu, Peoples R China

[4] Chinese Acad Sci, Inst Acoust, Beijing 100190, Peoples R China

[5] Huazhong Univ Sci & Technol, Sch Opt & Elect Informat, 1037 Luoyu Rd, Wuhan 430074, Hubei, Peoples R China

[6] Cent S Univ, Sch Mat Sci & Engn, State Key Lab Powder Met, Changsha 410083, Hunan, Peoples R China

[7] Northumbria Univ, Fac Engn & Environm, Newcastle Upon Tyne NE1 8ST, Tyne & Wear, England

关键词: Surface acoustic wave;    Gas sensor;    Colloidal quantum dots;    Nitrogen oxide;    Lead sulfide;   

DOI  :  10.1016/j.snb.2019.02.042

来源: Elsevier

【 摘 要 】

Surface acoustic wave (SAW) sensors have great advantages in real-time and in-situ gas detection due to their wireless and passive characteristics. Using nanostructured sensing materials to enhance the SAW sensor's responses has become a research focus in recent years. In this paper, solution-processed PbS colloidal quantum dots (CQDs) were integrated into quartz SAW devices for enhancing the performance of NO2 detection operated at room temperature. The PbS CQDs were directly spin-coated onto ST-cut quartz SAW delay lines, followed by a ligand exchange treatment using Pb(NO3)(2). Upon exposure to 10 ppm of NO2 gas, the sensor coated with untreated PbS CQDs showed response and recovery times of 487 s and 302 s, and a negative frequency shift of -2.2 kHz, mainly due to the mass loading effect caused by the absorption of NO2 gas on the surface of the dense CQD film. Whereas the Pb(NO3)(2)-treated sensor showed fast response and recovery times of 45 s and 58 s, and a large positive frequency shift of 9.8 kHz, which might be attributed to the trapping of NO2 molecules in the porous structure and thus making the film stiffer. Moreover, the Pb(NO3)(2)-treated sensor showed good stability and selectivity at room temperature.

【 授权许可】

Free