Efficient low-temperature detection of CO gas by various metalated porphyrinic-Al-based MOF (Cu and Co) materials

Abstract

A series of porphyrinic-Al-based metal–organic framework (MOF) nanomaterials were successfully fabricated via a simple solvothermal procedure and denoted as AlPMOF(M) (M = Cu, Co). The materials exhibited high surface areas with rectangular morphologies and the desired phases. Chemical composition studies demonstrated the presence of Cu and Co ions in the synthesized samples, while thermal studies showed the samples were stable up to 400 °C. CO gas-sensing studies revealed better CO sensing performances of both the AlPMOF(Cu) and AlPMOF(Co) gas sensors compared to the pristine sensor at room temperature. AlPMOF sensor showed responses of 1.06 and 1.05–10 ppm CO gas at 150 and 25ºC, respectively, with no selectivity to CO gas at 25ºC. AlPMOF (Co) sensor revealed responses of 1.11 and 1.06–10 ppm CO gas at 200 and 25ºC, respectively, with selectivity to CO gas at 25ºC. Also, AlPMOF (Cu) sensor revealed responses of 1.12 and 1.07–10 ppm CO gas at 150 and 25ºC, respectively, with selectivity to CO gas at 25ºC. In addition, the sensing mechanism and enhanced response to CO gas were elucidated. These findings demonstrate the capability of these novel sensing materials for CO gas sensing at low temperatures.