Turn-on type sensing of methanol vapor by a luminescent platinum(II) dichloride complex with 21-dibenzoarsacrown-7.

The development of turn-on detection sensors for methanol vapor remains challenging in materials science. Methanol sensing materials are generally based on vapor-triggered color changes or are turn-off types. Additionally, in general, the selectivity for methanol is limited, and the recyclability is low. Turn-on type sensing, high selectivity, rapid response time, and recyclability are favorable for achieving real-time detection systems. Herein, platinum(ii) dihalide (PtX2, X = Cl, Br, and I) complexes with 21-dibenzoarsacrown-7 were synthesized and their structures were characterized by single-crystal diffraction analysis. The PtCl2 complex showed intense emission when capturing methanol molecules in the crystalline matrix. In addition, this sensing system possessed high selectivity for methanol vapor and required facile recycling procedures.