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Lately novel strategies to enhance the sensing properties on iron oxide have been proposed to achieve high performance gas sensors for acetone detection. In this working report, the synthesis of iron-glycerate (Fe-Gly) using glycerol to combine with Fe3+ is first presented. Depending on the thermal treatment, this compound can evolve into γ-Fe2O3, α/γ-Fe2O3 and α-Fe2O3. α/γ-Fe2O3 shows better sensing performance as far as acetone detection is concerned. Using the dual phases of α/γ-Fe2O3 as a fundamental building block, their sensing properties were further improved using Ni doping and Ru nanoparticles functionalization. The high response and selectivity to acetone detection was ascribed to the synergistic effects of unique nanosheets, mixed phases, rich oxygen vacancies and excellent catalytic activity of Ru nanoparticles. [ABSTRACT FROM AUTHOR]

NiFe 2 O 4 is a promising sensing material for acetone detection, in which synthesizing 1D nanostructure and modulating the chemical composition are efficient strategies to enhance the sensing properties for multiple applications in reality. Herein, 1D precursor is hydrothermally synthesized using nitrilotriacetic acid (NTA) to chelate Fe3+ and Ni2+ ions. After thermal annealing, nanoparticles assembled 1D NiFe 2 O 4 nanorods with mesoporous structures are prepared. The porous 1D structure yields a large surface area (197.1 m2/g), exposes more active sites as well as offers a suitable backbone for Pt nanoparticles functionalization, facilitating acetone detection. The gas sensor based on Pt functionalized NiFe 2 O 4 nanorods exhibits high response of 48.2–100 ppm acetone at 160 °C with a rapid response and recovery time (10 s/26 s), low limits of detection (1 ppm), good selectivity, outstanding repeatability and reliable long-term durability (30 days). In addition, a good linearity of the response as a function of the acetone concentration from 1 to 200 ppm is fitted. These results may open a novel avenue to fabricate mesoporous 1D NiFe 2 O 4 that is an extremely promising candidate for acetone detection. [Display omitted] • Mesoporous 1D NiFe 2 O 4 nanorods were synthesized using nitrilotriacetic acid followed by thermal treatment. • The NiFe 2 O 4 nanorods are assembled by nanoparticles, exhibiting a surface area of 197.1 m2/g. • The NTA contents exert influence on the morphologies and the sensing properties of NiFe 2 O 4. • The sensing performance of mesoporous NiFe 2 O 4 nanorods is enhanced by Pt functionalization. [ABSTRACT FROM AUTHOR]

Crystalline iron oxide (Fe 2 O 3) shows great potential for acetone detection in multiple applications such as monitoring air pollution and diagnosing diabetes. α-Fe 2 O 3 or γ-Fe 2 O 3 are generally used as sensing materials. Here, we report a sol-gel method followed by a thermal treatment to control the phases formation of mesoporous iron oxide. We have found that mixed α/γ-Fe 2 O 3 phases exhibit enhanced sensing performances toward acetone. Moreover, as α/γ-Fe 2 O 3 is coupled with 2D materials of MXene (Ti 3 C 2 T x), the agglomeration of Fe 2 O 3 nanoparticles is prevented and the number of active sites for chemical absorption increased. Furthermore, the p-n heterojunctions lead to the enhancement of their response up to 148 towards 200 ppm of acetone at 200 °C. Additionally, Pt nanoparticles were be easily incorporated in between α/γ-Fe 2 O 3 and MXene to reduce the operating temperature down to 160 °C, while maintaining a very high response (307 towards 200 ppm) and lowering the detection limit to 0.5 ppm, thanks to the catalytic properties Pt nanoparticles. [ABSTRACT FROM AUTHOR]