One-pot synthesis of plate-like CeO2 nanosheets for sensing NH3 gas at room temperature

Plate-like CeO2 nanosheets were fabricated through a one-pot polyvinylpyrrolidone-assisted polyol process using the cerium-glycolate complex as the precursor at a low reaction temperature, followed by calcination. The morphology, phase composition, crystalline structure, specific surface area, and pore size distributions of plate-like CeO2 nanosheets were analyzed by scanning electron microscopy coupled with energy-dispersive X-ray elemental mapping, X-ray diffractometry, and N-2 adsorption-desorption testing. The formation process of plate-like CeO2 nanosheets was discussed in detail. The mesoporous structure of plate-like CeO2 nanosheets synthesized at 50 degrees C resulted in larger specific surface area of 99.77 m(2)/g and more pore size of 20 angstrom than those of were synthesized at 190 degrees C, which was beneficial to the absorption of NH3 gas. The NH3 gas sensor that was fabricated using the plate-like CeO2 nanosheets synthesized at 50 degrees C showed a high response (11.8%) even at a low concentration of NH3 of 0.1 ppm, a low detection limit (50 ppb) and good linearity (R-2 = 0.9279) over the range of 0.1-100 ppm of NH3 gas at mom temperature.

Automated summary

Plate-like CeO2 nanosheets were successfully synthesized using a specific method, with nanosheets synthesized at different temperatures exhibiting different pore size distributions and specific surface areas, affecting the absorption of NH3 gas. The nanosheets synthesized at 50°C showed excellent gas sensing performance towards NH3.