TY - JOUR
T1 - Cd doped ZnO nanorods for efficient room temperature NH3 sensing
AU - Brahma, Sanjaya
AU - Huang, P. C.
AU - Mwakikunga, B. W.
AU - Saasa, V.
AU - Akande, A. A.
AU - Huang, Jow Lay
AU - Liu, Chuan Pu
N1 - Funding Information:
This work was financially supported by the Hierarchical Green-Energy Materials (Hi-GEM) Research Center , from The Featured Areas Research Center Program within the framework of the Higher Education Sprout Project by the Ministry of Education (MOE) and the Ministry of Science and Technology ( MOST 111-2634-F-006-008 ) in Taiwan.
Publisher Copyright:
© 2022 Elsevier B.V.
PY - 2023/1/15
Y1 - 2023/1/15
N2 - We demonstrate room temperature (25 °C) and low temperature (≦100 °C) NH3 gas sensing properties of Cd-doped ZnO nanorods (NRs) synthesized by a low temperature (90 °C) hydrothermal method. Although, the Cd concentration in the growth solution was varied over a large range from 0 to 80 mol %, the maximum estimated Cd doping concentration in ZnO NRs was 0.5 at % (80 mol %). Structural analysis confirmed the successful doping of Cd in ZnO and microstructure investigation revealed the presence of single nanorod and flower like nanorods in the same ensemble whose dimensions reduced with the Cd doping concentration. Photoluminescence and Raman spectra analyses confirmed the increase of defect concentrations in ZnO NRs by Cd doping thereby enhancing the overall gas sensing. In response to NH3, the nanostructure sensors exhibited a gradual increase in the sensitivity with the Cd doping concentration where the 0.5 at % Cd-doped ZnO NRs showed the highest sensitivity with an enhancement of ∼9% (at 60 ppm NH3) as compared to the un-doped ZnO. The sensitivity continued to rise with the increase of temperature from 110% (25 °C), 120% (50 °C), 170% (75 °C) to 243% (100 °C) indicating a gigantic enhancement of ∼133% at 100 °C from 25 °C. The Cd-doped ZnO NRs also revealed superior specificity of detecting NH3 over NO2, and H2S even at room temperature.
AB - We demonstrate room temperature (25 °C) and low temperature (≦100 °C) NH3 gas sensing properties of Cd-doped ZnO nanorods (NRs) synthesized by a low temperature (90 °C) hydrothermal method. Although, the Cd concentration in the growth solution was varied over a large range from 0 to 80 mol %, the maximum estimated Cd doping concentration in ZnO NRs was 0.5 at % (80 mol %). Structural analysis confirmed the successful doping of Cd in ZnO and microstructure investigation revealed the presence of single nanorod and flower like nanorods in the same ensemble whose dimensions reduced with the Cd doping concentration. Photoluminescence and Raman spectra analyses confirmed the increase of defect concentrations in ZnO NRs by Cd doping thereby enhancing the overall gas sensing. In response to NH3, the nanostructure sensors exhibited a gradual increase in the sensitivity with the Cd doping concentration where the 0.5 at % Cd-doped ZnO NRs showed the highest sensitivity with an enhancement of ∼9% (at 60 ppm NH3) as compared to the un-doped ZnO. The sensitivity continued to rise with the increase of temperature from 110% (25 °C), 120% (50 °C), 170% (75 °C) to 243% (100 °C) indicating a gigantic enhancement of ∼133% at 100 °C from 25 °C. The Cd-doped ZnO NRs also revealed superior specificity of detecting NH3 over NO2, and H2S even at room temperature.
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U2 - 10.1016/j.matchemphys.2022.127053
DO - 10.1016/j.matchemphys.2022.127053
M3 - Article
AN - SCOPUS:85142395859
SN - 0254-0584
VL - 294
JO - Materials Chemistry and Physics
JF - Materials Chemistry and Physics
M1 - 127053
ER -