α-Fe2O3 derived from metal-organic frameworks as high performance sensing materials for acetone detection

High-performance gas sensors are critical for monitoring the environment, detecting health problems and ensuring safety. Metal-organic frameworks (MOFs) are considered promising gas-sensitive materials due to their elevated porosity, large specific surface area, and various morphologies. The conversion of MOFs into metal oxides can be achieved by oxidation and roasting processes, where the structure and surface chemical composition are significantly affected by the temperature at which the roasting is performed. The structures of α-Fe2O3 have been controlled by optimizing the heat treatment temperatures (350 °C, 400 °C, 450 °C and 500 °C) using MIL-100(Fe) as template which was synthesized using a hydrothermal method with reduced iron powder and 1,3,5-BTC as precursors. The gas sensitivity tests revealed that the α-Fe2O3 material obtained through annealing at 400 °C exhibited excellent sensitivity to acetone，which can be attributed to the combination of its porous structure and oxygen vacancy defects. Gas-sensitive materials, synthesized using MOFs as a template with meticulous tuning of the calcination temperature, exhibit exceptional properties. These materials hold great potential for advancing sensor materials in the field of gas sensor technology.