Highly sensitive temperature probe fabricated by high aspect ratio Eu-BTC nanowire

Metal-organic frameworks (MOFs) have shown great potential as a new platform for developing solid-state light-emitting temperature probes. Herein, we synthesized Eu-BTC (MOFs) with controllable nanowire and nanorod morphologies by changing solvents. Eu-BTC Nanowire was produced from DMF with a size of 15 µm and a 21.5 % photoluminescence quantum yield (PLQY), while the nanorods from H₂O yielded with a size of 200 nm (PLQY=17.4 %). The Eu-BTC materials exhibited highly variable temperature properties depending on the morphology. Eu-BTC Nanowire from DMF presented better temperature dependence as a highly sensitive temperature probe owing to its higher linearity and more excellent temperature-dependent reversibility, which further demonstrated its potential for application as a temperature probe. While, the Eu-BTC nanorod from H₂O showed a non-linear relationship with temperature and low temperature-dependent reversibility, making it unsuitable as a temperature probe. The morphologies-dependent luminescence sensing mechanism of Eu-BTCs and the heat conduction induced by surface defects mechanism were proposed. This work provides theoretical guidance for developing highly sensitive and non-contact temperature probes, especially for the morphology-dependent temperature probes.