Microwave-Assisted Synthesis and Gas-Sensing Performance of Hollow-Spherical WO₃ Nanocrystals

Abstract:

Hollow-spherical WO₃ nanocrystals were obtained by calcining an organic-inorganic W-C precursor containing C and W in a microwave oven or in a conventional muffle furnace, and the W-C precursor hybrid precursor was synthesized via a hydrothermal method. The samples were characterized by XRD, TG-DTA, FTIR and SEM. The morphologies of the WO₃ samples obtained by conventionally heating (C-WO₃) and microwave-assisted heating (M-WO₃) were compared. The average diameter and shell thickness of C-WO₃ hollow spheres is about 450 and 200 nm, respectively. The average diameter and shell thickness of M-WO₃ hollow spheres is about 500 and 50 nm, respectively. The M-WO₃ has a loose and multilayered shell, and their nanoparticles are smaller than those of C-WO₃. The improved structure of M-WO₃ is due to shorter heating time and the unique heating style in a microwave oven. The gas-sensing performances of the WO₃ sensors were investigated. The M-WO₃ sensor has better response to ethanol vapors than the C-WO₃.

• Periodical: Key Engineering Materials (Volumes 602-603)
• Pages: 46-50
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.602-603.46
• Online since: March 2014
• Authors: Li Yin, Gang Shao, Bing Bing Fan, De Liang Chen*, Rui Zhang
• Keywords: Gas-Sensing Materials, Hollow WO₃ Spheres, Hybrid Precursor, Microwave-Assisted Synthesis

References

[1] H. Zheng, Y. Tachibana, K. Kalantar-zadeh, Dye-Sensitized Solar Cells Based on WO3. Langmuir 26 (2010) 19148-19152.

DOI: 10.1021/la103692y

[2] C. Hammond, J. Straus, M. Righettoni, S. E. Pratsinis, I. Hermans, Nanoparticulate Tungsten Oxide for Catalytic Epoxidations. ACS Catal. 3 (2013) 321-327.

DOI: 10.1021/cs300826c

[3] L. You, Y. F. Sun, J. Ma, Y. Guan, J. M. Sun, Y. Du, G. Y. Lu, Highly Sensitive NO2 Sensor Based on Square-Like Tungsten Oxide Prepared with Hydrothermal Treatment. Sensor. Actuat. B-Chem. 157 (2011) 401-407.

DOI: 10.1016/j.snb.2011.04.071

[4] D. Chen, L. Gao, A. Yasumori, K. Kuroda, Y. Sugahara, Size- and Shape-Controlled Conversion of Tungstate-Based Inorganic-Organic Hybrid Belts to WO3 Nanoplates with High Specific Surface Areas. Small 4 (2008) 1813-1822.

DOI: 10.1002/smll.200800205

[5] B. B. Cao, J. J. Chen, X. J. Tang, W. L. Zhou, Growth of monoclinic WO3 nanowire array for highly sensitive NO2 detection. J. Mater. Chem. 19 (2009) 2323-2327.

DOI: 10.1039/b816646c

[6] N. Dahal, S. García, J. Zhou, S. M. Humphrey, Beneficial Effects of Microwave-Assisted Heating versus Conventional Heating in Noble Metal Nanoparticle Synthesis, ACS Nano 6 (2012) 9433-9446.

DOI: 10.1021/nn3038918

[7] I. Bilecka, P. Elser, M. Niederberger, Kinetic and Thermodynamic Aspects in the Microwave- Assisted Synthesis of ZnO Nanoparticles in Benzyl Alcohol, ACS Nano 3(2009) 467-477.

DOI: 10.1021/nn800842b

[8] Z. Ai, K. Deng, Q. Wan, L. Zhang, S. Lee, Facile Microwave-Assisted Synthesis and Magnetic and Gas Sensing Properties of Fe3O4 Nanoroses. J. Phys. Chem. C 114 (2010) 6237-6242.

DOI: 10.1021/jp910514f

[9] G. Qiu, S. Dharmarathna, Y. Zhang, N. Opembe, H. Huang, S. L. Suib, Facile Microwave-Assisted Hydrothermal Synthesis of CuO Nanomaterials and Their Catalytic and Electrochemical Properties. J. Phys. Chem. C 116 (2011) 468-477.

DOI: 10.1021/jp209911k

[10] D. Chen, L. Yin, L. Ge, B. Fan, R. Zhang, J. Sun, G. Shao, Low-Temperature and Highly Selective NO-Sensing Performance of WO3 Nanoplates Decorated with Silver Nanoparticles. Sensor. Actuat. B-Chem. 185 (2013) 445-455.

DOI: 10.1016/j.snb.2013.05.006