Electrostatic self-assembly of structurally tailored LDH-isopolyoxomolybdate nanohybrids for rapid detection of SO2 at room temperature

초록

The sluggish response and incomplete recovery of layered double hydroxides (LDHs) at room temperature limit their application in next-generation gas sensors. In this work, nanohybrids composed of two-dimensional zinc chromium layered double hydroxide (ZnCr-LDH) nanosheets and zero-dimensional isopolyoxomolybdate (iPOM) nanoclusters, hereafter referred to as ZCiM (ZnCr-LDH/iPOM), were synthesized via electrostatic self-assembly for efficient SO2 detection at room temperature. The 2D-0D integration modulates the interfacial and surface properties of ZnCr-LDH, resulting in notable enhanced sensing performance. The optimized ZCiM-2 sensor exhibits a high response of 84.45%, a rapid response time of 14 s, and an ultra-low detection limit of 14 ppb, together with excellent repeatability, selectivity, and humidity tolerance. These improvements originate from increased active sites, ultrathin morphology, and efficient interfacial charge transfer. The results demonstrate the potential of ZCiM nanohybrids for practical room-temperature SO2 sensing.

키워드