One-Step Hydrothermal Synthesis of Fe2(Moo4)3 Functionalized Α-Moo3 Nanoplates with Enhanced Gas Sensing Properties

Abstract

The synthesis method for heterojunctions is usually a two-step method, typically involving the synthesis of a support first, followed by the loading of metal oxides or metal molybdates. In this study, we propose a simple one-step hydrothermal method for preparing two-dimensional (2D) Fe2(MoO4)3-functionalized α-MoO3 nanoplates in the presence of lactic acid, without the need to add surfactants or templates. To examine the microstructure, morphology, and chemical compositions of the Fe2(MoO4)3/α-MoO3 heterostructures, a variety of techniques were utilized. The experimental results confirm that the Fe2(MoO4)3/α-MoO3 heterojunctions are successfully obtained, and the Fe2(MoO4)3 nanoparticles display uniform distribution over the α-MoO3 surface as the loading amount is appropriate. Gas sensing tests for several typical organic gases demonstrated that the Fe2(MoO4)3/α-MoO3-based sensor had significantly higher responses to ethanol and acetone than the pure α-MoO3-based sensor. Moreover, it also showed rapid response - recovery speeds, as well as good reproducibility and stability, suggesting its potential in gas sensing applications. The outstanding gas sensing performance might be attributed to the existence of α-MoO3-Fe2(MoO4)3 heterojunctions and the catalytic effect of Fe2(MoO4)3 nanoparticles.

Keywords: α-MoO3 nanoplates, Fe2(MoO4)3, Heterojunction, Sensor, VOCs detection