Room Temperature Flexible Gas Sensor Based on MOF-Derived Porous Carbon Skeletons Loaded with ZnO Nanoparticles and DMF Detection
Xiaoli Xu, Guorong Sun, Mengyu Wang, Hongtao Jiang, Wei Ma, Wangwang Liu, Zhihong Jin, Jiamin Zhu, Guoqing Chang, S.Y. Ma
Abstract
Overcoming the persistent challenges of high operating temperatures and poor selectivity in metal oxide semiconductor (MOS) gas sensors, this work enhances defect sites in the sensing material through heterostructure construction and builds mesoporous architectures using MOF-derived carbon skeletons as templates. The synergistic effects of multiple mechanisms significantly improve gas-sensing performance, successfully fabricating a ZnO/PCS flexible room-temperature gas sensor with exceptional room-temperature DMF detection capabilities. The nitrogen-containing porous carbon skeletons (PCSs) template shows a stable mesoporous microstructure with large pore volume. Further gas-sensitive investigations show that the ZnO/PCS flexible sensor presents high sensitivity (100 ppm of DMF, 68.06%), reduced response/recovery time (44 s/45 s), and low limit of detection (15.74 ppb) at room temperature (RT). In addition, the response decreases by only 5.65% after 200 bends, which proves the good flexible stability of the sensor. It is worth noting that hydrophobic PCSs also contribute to the good moisture resistance of the ZnO/PCS FRT sensor. The composite of ZnO and PCS porous carbon skeleton forms heterogeneous interfaces. The resulting ZnO/PCS heterostructure achieves remarkable characteristics: an ultrahigh specific surface area (214.86 m 2 g –1 ), abundant oxygen vacancies (66.06%), and nitrogen-facilitated electron transfer-collectively enabling superior surface redox activity upon gas exposure. This work verifies a possible and facile strategy for the realization of FRT sensing metal oxide semiconductors by using MOF-derived PCSs, which may have great application potential in the field of flexible RT sensors.