Researchers prepared pure MoO₃ and three Ni-doped compositions by a hydrothermal route, corresponding to Ni/Mo molar ratios of 0, 2.5, 5.0 and 7.5 mol%. They characterized the resulting materials using X-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy with energy-dispersive spectroscopy, X-ray photoelectron spectroscopy, and nitrogen adsorption–desorption analysis. These methods allowed the team to relate the samples’ crystal structures, morphologies, surface chemical states and porosity to their gas-sensing behavior.

Among the four compositions evaluated, the 5.0 mol% Ni-doped material delivered the strongest overall performance. It also showed what the researchers described as superior selectivity under the reported test conditions. Its short response time and longer recovery time mean that the signal rose rapidly and then returned to baseline more gradually.

The supplied abstract does not specify the individual replicate counts or uncertainty intervals for every measurement, although it reports that operation varied by less than 5% over the 10-day stability assessment. The authors attributed the improvement to the combined influence of the nanohollow architecture and nickel incorporation. The hollow, porous spheres were associated with a larger specific surface area, while the Ni-containing material showed an increase in surface species related to oxygen vacancies.

The authors also linked the sensing enhancement to catalytic and spillover effects introduced by nickel. In the source’s interpretation, these features jointly contributed to the higher response, lower optimum operating temperature, rapid sensing and resistance to humidity interference. The study does not establish how each contribution would behave independently, and the available evidence is limited to laboratory characterization and sensor measurements performed on the synthesized materials.

Within that experimental scope, the results show that a moderate nickel concentration of 5.0 mol% can improve the acetone-sensing performance of MoO₃ nanohollow spheres while allowing operation at a lower temperature.

Subject of Research: Laboratory evaluation of nickel-doped MoO₃ nanohollow spheres for acetone gas sensing.

Article Title: Synthesis of Ni-doped MoO3 nanohollow spheres and investigation of gas-sensing performance to acetone

Article References: Cao, H., Li, X., Zhang, H., Jia, X., Jia, J., Ma, K., Zhou, C., & Liu, S. (2026). Synthesis of Ni-doped MoO3 nanohollow spheres and investigation of gas-sensing performance to acetone. Journal of Materials Science, 61(40), 30651-30664. https://doi.org/10.1007/s10853-026-13659-y

Image Credits: AI Generated

DOI: 10.1007/s10853-026-13659-y

Keywords: nickel-doped MoO₃, acetone sensing, nanohollow spheres, metal-oxide sensors, hydrothermal synthesis, surface chemistry, oxygen vacancies, gas selectivity, humidity resistance, operating temperature, Synthesis, Ni-doped