Газовий датчик на основі нанорозмірних напівпровідникових гетероструктур ZnS/CdS, що працює при кімнатній температурі

• Date: 2017
• Main Authors: Prokopenko, S. L., Gunya, G. M., Makhno, S. M., Gorbyk, P. P.
• Format: Article
• Language: English
• Published: Chuiko Institute of Surface Chemistry National Academy of Sciences of Ukraine 2017
• Subjects: датчик; ZnS/CdS гетероструктури; NH3; ацетон; нанострижні
• Online Access: https://www.cpts.com.ua/index.php/cpts/article/view/446
• Journal Title: Chemistry, Physics and Technology of Surface

Nanoscale heterostructures ZnS/CdS have been synthesized in order to put into effect those gas sensors, which work at room temperature. Synthesis was carried out in two stages. The first stage is the formation of CdS nanorods. The second stage is solvothermal approach, it leads to deposition and growth of a ZnS particles on CdS nanoparticles. A number of samples with different molar ratio Zn/Cd were synthesized.The XRD method shows appearance of the cubic phase of ZnS on hexagonal CdS. The size of the synthesized ZnS/CdS nanorods is an average length of 150–200 nm and a thickness approximately of 20 nm. Optical spectra for all the synthesized samples were recorded in the wavelength ranging of 350–800 nm at room temperature. The band gap of the synthesized CdS nanorods is 2.40 eV, those of the heterostructures 0.75 ZnS/CdS and 1.0 ZnS/CdS are 2.38 and 2.35 eV respectively.The dynamic response characteristics of sensors was measured in air and in the presence of acetone or ammonia gas. The measurement was performed at room temperature. Each exposure/recovery cycle was carried out for an exposure interval of 200–250 s followed by a recovery interval of 200 s in air. With an increase of amount of the ZnS on the CdS surface, the response of the sensor increases respectively. All the investigated sensors based on ZnS/CdS heterostructures have better sensitivity for NH3 atmosphere (for 0.75 ZnS/CdS about 1.4 times higher) in comparison with acetone atmosphere.