Work function based gas sensing with Cu-BTC metal-organic framework for selective aldehyde detection

Metal-organic frameworks (MOFs) are porous crystalline materials with a characteristic large surface area. These materials were mainly investigated for applications such as gas storage and separation and catalysis. The applicability of MOFs for gas sensing was already successfully demonstrated. MOFs show high potential for applications involving work function based gas sensing devices. In this work the Cu-BTC MOF was investigated as a selective aldehyde sensing material for work function read-out based gas sensors at ambient conditions. The cross sensitivity to humidity and the influence of oxygen on the gas reaction were proved. The possible reaction mechanism between gas and sensing layer is discussed. It is shown that Cu-BTC MOF sensing layers allow to distinguish hydrocarbon molecules with similar chemical properties but different lengths of the organic chain.