Synthesis and Physical Characteristics of Undoped and Potassium-Doped Cubic Tungsten Trioxide Nanowires through Thermal Evaporation
We report an efficient method to synthesize undoped and K-doped rare cubic tungsten trioxide nanowires through the thermal evaporation of WO<sub>3</sub> powder without a catalyst. The WO<sub>3</sub> nanowires are reproducible and stable with a low-cost growth process. The the...
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MDPI AG
2023-03-01
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| Series: | Nanomaterials |
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| Online Access: | https://www.mdpi.com/2079-4991/13/7/1197 |
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| author | Po-Heng Sung Hsi-Kai Yen Shu-Meng Yang Kuo-Chang Lu |
| author_facet | Po-Heng Sung Hsi-Kai Yen Shu-Meng Yang Kuo-Chang Lu |
| author_sort | Po-Heng Sung |
| collection | DOAJ |
| description | We report an efficient method to synthesize undoped and K-doped rare cubic tungsten trioxide nanowires through the thermal evaporation of WO<sub>3</sub> powder without a catalyst. The WO<sub>3</sub> nanowires are reproducible and stable with a low-cost growth process. The thermal evaporation processing was conducted in a three-zone horizontal tube furnace over a temperature range of 550–850 °C, where multiple substrates were placed at different temperature zones. The processing parameters, including pressure, temperature, type of gas, and flow rate, were varied and studied in terms of their influence on the morphology, aspect ratio and density of the nanowires. The morphologies of the products were observed with scanning electron microscopy. High resolution transmission electron microscopy, X-ray photoelectron spectroscopy, and X-ray diffraction studies were conducted to further identify the chemical composition, crystal structure and growth direction of the nanostructures. Additionally, the growth mechanism has been proposed. Furthermore, we investigated the potassium doping effect on the physical properties of the nanostructures. Photoluminescence measurements show that there were shorter emission bands at 360 nm and 410 nm. Field emission measurements show that the doping effect significantly reduced the turn-on electric field and increased the enhancement factor. Furthermore, as compared with related previous research, the K-doped WO<sub>3</sub> nanowires synthesized in this study exhibited excellent field emission properties, including a superior field enhancement factor and turn-on electric field. The study reveals the potential of WO<sub>3</sub> nanowires in promising applications for sensors, field emitters and light-emitting diodes. |
| first_indexed | 2024-03-11T05:28:30Z |
| format | Article |
| id | doaj.art-2c843b65de7d46a2b4c0155699de9e91 |
| institution | Directory Open Access Journal |
| issn | 2079-4991 |
| language | English |
| last_indexed | 2024-03-11T05:28:30Z |
| publishDate | 2023-03-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Nanomaterials |
| spelling | doaj.art-2c843b65de7d46a2b4c0155699de9e912023-11-17T17:17:06ZengMDPI AGNanomaterials2079-49912023-03-01137119710.3390/nano13071197Synthesis and Physical Characteristics of Undoped and Potassium-Doped Cubic Tungsten Trioxide Nanowires through Thermal EvaporationPo-Heng Sung0Hsi-Kai Yen1Shu-Meng Yang2Kuo-Chang Lu3Department of Materials Science and Engineering, National Cheng Kung University, Tainan 701, TaiwanDepartment of Materials Science and Engineering, National Cheng Kung University, Tainan 701, TaiwanDepartment of Materials Science and Engineering, National Cheng Kung University, Tainan 701, TaiwanDepartment of Materials Science and Engineering, National Cheng Kung University, Tainan 701, TaiwanWe report an efficient method to synthesize undoped and K-doped rare cubic tungsten trioxide nanowires through the thermal evaporation of WO<sub>3</sub> powder without a catalyst. The WO<sub>3</sub> nanowires are reproducible and stable with a low-cost growth process. The thermal evaporation processing was conducted in a three-zone horizontal tube furnace over a temperature range of 550–850 °C, where multiple substrates were placed at different temperature zones. The processing parameters, including pressure, temperature, type of gas, and flow rate, were varied and studied in terms of their influence on the morphology, aspect ratio and density of the nanowires. The morphologies of the products were observed with scanning electron microscopy. High resolution transmission electron microscopy, X-ray photoelectron spectroscopy, and X-ray diffraction studies were conducted to further identify the chemical composition, crystal structure and growth direction of the nanostructures. Additionally, the growth mechanism has been proposed. Furthermore, we investigated the potassium doping effect on the physical properties of the nanostructures. Photoluminescence measurements show that there were shorter emission bands at 360 nm and 410 nm. Field emission measurements show that the doping effect significantly reduced the turn-on electric field and increased the enhancement factor. Furthermore, as compared with related previous research, the K-doped WO<sub>3</sub> nanowires synthesized in this study exhibited excellent field emission properties, including a superior field enhancement factor and turn-on electric field. The study reveals the potential of WO<sub>3</sub> nanowires in promising applications for sensors, field emitters and light-emitting diodes.https://www.mdpi.com/2079-4991/13/7/1197cubic tungsten oxidethermal evaporationnanowiresphotoluminescencedopingfield-emission |
| spellingShingle | Po-Heng Sung Hsi-Kai Yen Shu-Meng Yang Kuo-Chang Lu Synthesis and Physical Characteristics of Undoped and Potassium-Doped Cubic Tungsten Trioxide Nanowires through Thermal Evaporation Nanomaterials cubic tungsten oxide thermal evaporation nanowires photoluminescence doping field-emission |
| title | Synthesis and Physical Characteristics of Undoped and Potassium-Doped Cubic Tungsten Trioxide Nanowires through Thermal Evaporation |
| title_full | Synthesis and Physical Characteristics of Undoped and Potassium-Doped Cubic Tungsten Trioxide Nanowires through Thermal Evaporation |
| title_fullStr | Synthesis and Physical Characteristics of Undoped and Potassium-Doped Cubic Tungsten Trioxide Nanowires through Thermal Evaporation |
| title_full_unstemmed | Synthesis and Physical Characteristics of Undoped and Potassium-Doped Cubic Tungsten Trioxide Nanowires through Thermal Evaporation |
| title_short | Synthesis and Physical Characteristics of Undoped and Potassium-Doped Cubic Tungsten Trioxide Nanowires through Thermal Evaporation |
| title_sort | synthesis and physical characteristics of undoped and potassium doped cubic tungsten trioxide nanowires through thermal evaporation |
| topic | cubic tungsten oxide thermal evaporation nanowires photoluminescence doping field-emission |
| url | https://www.mdpi.com/2079-4991/13/7/1197 |
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