Abstract
Herein, we report a chemi-resistive sensing method for the detection of formaldehyde (HCHO) gas. For this, alpha-MnO2 nanowires were synthesized hydrothermally and examined for ascertaining their chemical composition, crystal phase, morphology, purity, and vibrational properties. The XRD pattern confirmed the high crystallinity and purity of the alpha-MnO2 nanowires. FESEM images confirmed a random orientation and smooth-surfaced wire-shaped morphologies for as-synthesized alpha-MnO2 nanowires. Further, the synthesized nanowires with rounded tips had a uniform diameter throughout the length of the nanowires. The average diameter of the alpha-MnO2 nanowires was found to be 62.18 nm and the average length was similar to 2.0 mu m. Further, at an optimized temperature of 300 degrees C, the fabricated HCHO sensor based on alpha-MnO2 nanowires demonstrated gas response, response, and recovery times of 19.37, 18, and 30 s, respectively.