Selectively detecting toluene and benzaldehyde by two stable lanthanide–organic frameworks as luminescent probes

Abstract

Benzene derivatives are seriously harmful to environment and human health, and sensitively detecting these compounds is of great significance but is a challenge. Hence, we designed and synthesized two luminescent lanthanide–organic frameworks, [{Ln(SIP)(H₂O)₄}]_n, [Ln = Tb (1), Eu (2)], with high solvent and pH stability, which can be used as luminescent probes to detect toluene and benzaldehyde among various reagents, and the detection limit can reach up to 10⁻⁷ mol L⁻¹ for toluene, and 10⁻⁶ mol L⁻¹ for benzaldehyde. Regenerated experimental results indicate that both 1 and 2 can be used for at least five cycles with high precision. To the best of our knowledge, this is the first example of the two-dimensional regenerable luminescent sensor for toluene and benzaldehyde through luminescent quenching.