1. Selective H2S-sensing performance of Si nanowires through the formation of ZnO shells with Au functionalization
- Author
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Wansik Oum, Jae Hoon Bang, Sang Sub Kim, Yong Jung Kwon, Sun Woo Choi, Ali Mirzaei, Myung Sik Choi, Hyoun Woo Kim, and Jae-Hun Kim
- Subjects
Materials science ,Thin layer ,Metals and Alloys ,Nanowire ,Nanoparticle ,Heterojunction ,02 engineering and technology ,engineering.material ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Chemical engineering ,Coating ,Materials Chemistry ,engineering ,Surface modification ,Oxidation process ,Electrical and Electronic Engineering ,0210 nano-technology ,Selectivity ,Instrumentation - Abstract
A novel gas sensor fabricated from ZnO-shelled Si nanowires (SiNWs) is presented. After coating a thin layer of Au on the surfaces of Si NWs, ZnO layers were formed on the surfaces of p-SiNWs by thermal evaporation of Zn powders and a subsequent oxidation process. Microscopic analysis confirmed the successful formation of ZnO-Si core-shell NWs with Au nanoparticles present on the shell surface. The gas sensing performance of the gas sensor fabricated using the p-Si/n-ZnO core-shell NWs was evaluated for various gases. The sensor exhibited outstanding response and selectivity to H2S gas. The gas sensing mechanism was evaluated in detail and attributed to various factors, including the formation of ZnO/Si and Au/ZnO heterojunctions and the chemical attraction between ZnO and Au. The results demonstrate a new sensing material for H2S detection in various fields that can be easily incorporated into Si-based devices.
- Published
- 2019
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