Tb post-functionalized La (III) metal organic framework hybrid probe for simple and highly sensitive detection of acetaldehyde

•A novel highly fluorescent hybrid (Tb@La-MOF) as a probe.•Selective detection of acetaldehyde with low detection limit, rapid response.•Resistance to water and wide pH value range (3.35–11.75).•A candidate for practical sensing of liquid acetaldehyde and acetaldehyde vapor. A novel highly fluorescent hybrid system called Tb@La-MOF (Tb@{[La(hisp)(Hhisp)(H2O)2]·2H2O}n) has been synthesized via post-synthetic modification of metal-organic framework centered on inert lanthanum ion. With excellent luminescent properties, Tb@La-MOF is developed as a fluorescent probe for acetaldehyde detection, notably, it can distinguish acetaldehyde specifically from a series of other organic molecules. More importantly, water-stable Tb@La-MOF exhibits advantages like low detection limit (0.00058% for water with acetaldehyde, volume fraction), rapid response, and resistance to decompose over a wide range of pH values (3.35–11.75). Therefore, it is expected to be a promising candidate for both practical sensing on liquid acetaldehyde and simple detection of acetaldehyde vapor. Besides, the possible sensing mechanism is discussed.