Ag nanorods assembled with ZnO nanowalls for near-linear high-response UV photodetectors

• Published in: Journal of alloys and compounds 2020-07, Vol.830, p.154652, Article 154652
• Main Authors: Li, Chun, Yu, Lingmin, Yuan, Xiong, Li, Yuan, Ning, Nan, Cui, Le, Ma, Shuai, Kang, Weigang, Fan, Xinhui
• Format: Article
• Language: English
• Subjects: Ag nanorods; Doppler effect; Heterojunctions; Heterostructures; Nanorods; Near-liner; Photometers; Red shift; Silver; UV photodetectors; Zinc oxide; ZnO nanowalls; ZnO/Ag heterostructure
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2020.154652

We developed a simple method of sonication combined with annealing treatment method to construct ZnO/Ag heterostructures from Ag nanorods assembled in-situ with ZnO nanowalls, which were then characterized by FESEM, EDS, XRD, XPS, PL, UV-vis spectra. A perfect heterojunction was formed by Ag nanorods inserted into the holes of 3D ZnO nanowalls. Compared with pure ZnO nanowalls, the ZnO/Ag heterostructures have more vacancy defects and a red shift in absorption. The effects of the working temperature on sensors fabricated with ZnO/Ag heterojunction were investigated. The photodetector demonstrated higher photo response activity as well as a faster response speed and excellent environmental stability compared to pristine ZnO nanowalls, and the photoresponse exhibited a better linear relationship at 10 °C ∼70 °C. The mechanism of UV photo sensing for the ZnO/Ag heterojunction was discussed. The results indicated that ZnO/Ag heterojunction could act as an interesting material for UV photodetectors with near-linear responses in outdoor temperatures. [Display omitted] •A new approach of Ag nanorods in-situ assembled with ZnO nanowalls was established.•ANear-linearhigh response UV photodetectorin outdoor temperature was constructed.•The mechanism of UV photo sensing for ZnO/Ag heterojunctionwas discussed.