Green hydrothermal synthesis of Ga doping derived 3D ZnO nanosatellites for high sensitive gas sensors

A green hydrothermal synthesis methodology is employed for the synthesis of Ga3+ doped ZnO 3D nanosatellite structures. XRD technique exposed the hexagonal wurtzite type crystal structure of the 3D Ga3+ doped ZnO nanostructures. Ga3+ induced 3D morphology evolution in accordance to Ga doping concentration is realized via. the FESEM images. The FESEM images indicated one sided capped rod like structures (50-250 nm) in pristine ZnO, whereas 3D satellite kind of morphology (>500 nm) was observed in 5% Ga3+ doped ZnO structures. TEM images revealed physical specifications of 3D nanosatellite structures exposing the central rod of 500 nm length & 250 nm in width and the branch rods grown vertical to the central rod of length 300 nm and width of 50 nm. Further, optical absorbance and photoluminescence spectra confirmed the electron rich state of ZnO with Ga3+ doping. The gas sensing performance has shown selectivity toward CO gas at a working temperature of 250 degrees C. High CO sensing was recorded for 5% Ga3+ doped ZnO 3D nanosatellites with attractive sensing characteristics such as good response, fast response time & fast recovery time.

Automated summary

A green hydrothermal synthesis method was used to synthesize Ga3+ doped ZnO 3D nanosatellite structures. XRD analysis revealed the crystal structure of the nanostructures to be hexagonal wurtzite type. FESEM images showed the evolution of 3D morphology in accordance with Ga doping concentration. TEM images provided physical specifications of the 3D nanosatellite structures. Optical absorbance and photoluminescence spectra confirmed the electron rich state of Ga3+ doped ZnO. Gas sensing performance of the nanosatellites showed selectivity towards CO gas at a working temperature of 250 degrees C, with 5% Ga3+ doped ZnO exhibiting high CO sensing and attractive sensing characteristics.