Synthesis and gas-sensing properties of ZnO nanoflowers for hydrogen sulphide (H2S) detection

Herein, we report the synthesis, characterization, and gas sensing properties of zinc oxide (ZnO) nanoflowers grown by facile simple solution process. The synthesized ZnO nanoflowers were examined by various techniques to explore their structural, morphological, optical, compositional and gas sensing properties. The details morphological and structural characterizations revealed that the synthesized material possessed flower-shaped morphologies in the nanoscale range with a wurtzite hexagonal crystal structure of ZnO. The high-intense peaks of the synthesized ZnO nanoflowers confirmed high crystallinity. Furthermore, the synthesized ZnO nanoflowers were used as an electrode material to fabricate a facile and low-cost gas sensor to detect hydrogen sulphide (H2S). At an ideal working temperature of 150 °C, the ZnO nanoflowers electrode-based gas sensor displayed remarkable selectivity, good response (48 s), and recovery (97 s) time. Moreover, the fabricated gas sensor exhibited a maximum gas response of 139 (Rg/Ra) towards 50 ppm hydrogen sulphide gas at 150 °C. The unique performance of the ZnO nanoflowers-based gas sensor was attributed to the large surface area of the ZnO nanoflowers, which enabled the fabricated sensor to be a contender for the detection of H2S gas among the wide variety of reported sensors.