Selective H Gas Sensing Using ZIF-71/In-SnO Bilayer Sensors: A Size-Selective Molecular Sieving Approach.

A universal method for creating selective hydrogen (H) gas sensors through the integration of microporous zeolitic imidazolate framework (ZIF) filter layers on metal oxide sensing layers is presented. The sensor design consists of an indium-modified tin oxide (In-SnO) layer as the gas-sensitive component, topped by a size-selective ZIF filter layer. The ZIF layer is generated by first depositing zinc oxide (ZnO) of variable thickness (20-48 nm) onto the In-SnO layer, followed by in situ conversion to either ZIF-8 or ZIF-71 through solvothermal methods.