Reduced graphene oxide conjugated Cu2O nanowire mesocrystals for high-performance NO2 gas sensor
Reduced graphene oxide (rGO)-conjugated Cu2O nanowire mesocrystals were formed by nonclassical crystallization in the presence of GO and o-anisidine under hydrothermal conditions. The resultant mesocrystals are comprised of highly anisotropic nanowires as building blocks and possess a distinct octah...
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sg-ntu-dr.10356-977552020-06-01T10:21:24Z Reduced graphene oxide conjugated Cu2O nanowire mesocrystals for high-performance NO2 gas sensor Mhaisalkar, Subodh Gautam Olivo, Malini Sayle, Dean C. Deng, Suzi Tjoa, Verawati Fan, Hai Ming Tan, Hui Ru Wei, Jun Sow, Chorng Haur School of Materials Science & Engineering A*STAR SIMTech Reduced graphene oxide (rGO)-conjugated Cu2O nanowire mesocrystals were formed by nonclassical crystallization in the presence of GO and o-anisidine under hydrothermal conditions. The resultant mesocrystals are comprised of highly anisotropic nanowires as building blocks and possess a distinct octahedral morphology with eight {111} equivalent crystal faces. The mechanisms underlying the sequential formation of the mesocrystals are as follows: first, GO-promoted agglomeration of amorphous spherical Cu2O nanoparticles at the initial stage, leading to the transition of growth mechanism from conventional ion-by-ion growth to particle-mediated crystallization; second, the evolution of the amorphous microspheres into hierarchical structure, and finally to nanowire mesocrystals through mesoscale transformation, where Ostwald ripening is responsible for the growth of the nanowire building blocks; third, large-scale self-organization of the mesocrystals and the reduction of GO (at high GO concentration) occur simultaneously, resulting in an integrated hybrid architecture where porous three-dimensional (3D) framework structures interspersed among two-dimensional (2D) rGO sheets. Interestingly, “super-mesocrystals” formed by 3D oriented attachment of mesocrystals are also formed judging from the voided Sierpinski polyhedrons observed. Furthermore, the interior nanowire architecture of these mesocrystals can be kinetically controlled by careful variation of growth conditions. Owing to high specific surface area and improved conductivity, the rGO-Cu2O mesocrystals achieved a higher sensitivity toward NO2 at room temperature, surpassing the performance of standalone systems of Cu2O nanowires networks and rGO sheets. The unique characteristics of rGO-Cu2O mesocrystal point to its promising applications in ultrasensitive environmental sensors. 2013-07-11T08:10:38Z 2019-12-06T19:46:09Z 2013-07-11T08:10:38Z 2019-12-06T19:46:09Z 2012 2012 Journal Article Deng, S., Tjoa, V., Fan, H. M., Tan, H. R., Sayle, D. C., Olivo, M., et al. (2012). Reduced Graphene Oxide Conjugated Cu 2 O Nanowire Mesocrystals for High-Performance NO 2 Gas Sensor . Journal of the American Chemical Society, 134(10), 4905-4917. https://hdl.handle.net/10356/97755 http://hdl.handle.net/10220/11233 10.1021/ja211683m en Journal of the American chemical society © 2012 American Chemical Society. |
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Reduced graphene oxide (rGO)-conjugated Cu2O nanowire mesocrystals were formed by nonclassical crystallization in the presence of GO and o-anisidine under hydrothermal conditions. The resultant mesocrystals are comprised of highly anisotropic nanowires as building blocks and possess a distinct octahedral morphology with eight {111} equivalent crystal faces. The mechanisms underlying the sequential formation of the mesocrystals are as follows: first, GO-promoted agglomeration of amorphous spherical Cu2O nanoparticles at the initial stage, leading to the transition of growth mechanism from conventional ion-by-ion growth to particle-mediated crystallization; second, the evolution of the amorphous microspheres into hierarchical structure, and finally to nanowire mesocrystals through mesoscale transformation, where Ostwald ripening is responsible for the growth of the nanowire building blocks; third, large-scale self-organization of the mesocrystals and the reduction of GO (at high GO concentration) occur simultaneously, resulting in an integrated hybrid architecture where porous three-dimensional (3D) framework structures interspersed among two-dimensional (2D) rGO sheets. Interestingly, “super-mesocrystals” formed by 3D oriented attachment of mesocrystals are also formed judging from the voided Sierpinski polyhedrons observed. Furthermore, the interior nanowire architecture of these mesocrystals can be kinetically controlled by careful variation of growth conditions. Owing to high specific surface area and improved conductivity, the rGO-Cu2O mesocrystals achieved a higher sensitivity toward NO2 at room temperature, surpassing the performance of standalone systems of Cu2O nanowires networks and rGO sheets. The unique characteristics of rGO-Cu2O mesocrystal point to its promising applications in ultrasensitive environmental sensors. |
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School of Materials Science & Engineering |
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School of Materials Science & Engineering Mhaisalkar, Subodh Gautam Olivo, Malini Sayle, Dean C. Deng, Suzi Tjoa, Verawati Fan, Hai Ming Tan, Hui Ru Wei, Jun Sow, Chorng Haur |
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Mhaisalkar, Subodh Gautam Olivo, Malini Sayle, Dean C. Deng, Suzi Tjoa, Verawati Fan, Hai Ming Tan, Hui Ru Wei, Jun Sow, Chorng Haur |
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Mhaisalkar, Subodh Gautam Olivo, Malini Sayle, Dean C. Deng, Suzi Tjoa, Verawati Fan, Hai Ming Tan, Hui Ru Wei, Jun Sow, Chorng Haur Reduced graphene oxide conjugated Cu2O nanowire mesocrystals for high-performance NO2 gas sensor |
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Mhaisalkar, Subodh Gautam |
title |
Reduced graphene oxide conjugated Cu2O nanowire mesocrystals for high-performance NO2 gas sensor |
title_short |
Reduced graphene oxide conjugated Cu2O nanowire mesocrystals for high-performance NO2 gas sensor |
title_full |
Reduced graphene oxide conjugated Cu2O nanowire mesocrystals for high-performance NO2 gas sensor |
title_fullStr |
Reduced graphene oxide conjugated Cu2O nanowire mesocrystals for high-performance NO2 gas sensor |
title_full_unstemmed |
Reduced graphene oxide conjugated Cu2O nanowire mesocrystals for high-performance NO2 gas sensor |
title_sort |
reduced graphene oxide conjugated cu2o nanowire mesocrystals for high-performance no2 gas sensor |
publishDate |
2013 |
url |
https://hdl.handle.net/10356/97755 http://hdl.handle.net/10220/11233 |
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