Mace-like TTF-TCNQ/HKUST-1 composite structures for rapid NO₂ detection: Synergistically induced ultrahigh sensitivity and outstanding selectivity

Integration and synergy of the unique functions of different components have been developed into one of the most convenient and effective ways to construct the composite advanced materials with collective properties and improved performances. In this work, the mace-like tetrathiafulvalene-tetracyanoquinodimethane (TTF-TCNQ)/HKUST-1 composite structures with single single-crystalline TTF-TCNQ submicrorods covered by ordered HKUST-1 nanosheet arrays were successfully constructed by an efficient TTF-TCNQ seed-mediated growth approach. Impressively, thanks to the synergetic and complementary effects between TTF-TCNQ and HKUST-1, the sensors based on such mace-like TTF-TCNQ/HKUST-1 composite structures not only displayed an experimental detection limit of 10 part per billion (ppb) for NO₂ detection, but also exhibited outstanding selectivity even if the concentration of the interfering gases was 10 times that of NO₂. Meanwhile, good reproducibility and rapid response were also achieved. This work opens the avenue for creation of novel high-performance sensing materials for application in gas sensing.