Smart sensing device for formaldehyde that based on uniform lanthanide CPs microsphere

•A stable, highly selective and sensitive lanthanide sensor towards toxic pollutant of formaldehyde is designed.•The sensor was fabricated into uniform microspheres, and further molded into smart detection device of test paper for naked eye detection of formaldehyde.•The sensing mechanism is revealed by luminescence lifetimes comparison. Formaldehyde is toxic to human body and animals, thus sensing of low concention of formaldehyde is urgent. A new uniform luminescent and stable lanthanide microsphere of europium complex sensor (Eu-MTFBA) towards formaldehyde in water is developed. Single crystal analysis shows the microsphere has a one dimensional (1D) coordination polymer structure. The sensor was further molded into smart detection device of test paper, which is applied to detect formaldehyde through naked eyes. Furthermore, the sensing mechanism is also revealed by luminescence lifetimes measurement. A stable, highly selective and sensitive lanthanide sensor towards toxic pollutant of formaldehyde is designed. The sensor was fabricated into uniform microspheres, and further molded into smart detection device of test paper for naked eye detection of formaldehyde. The sensing mechanism is revealed by luminescence lifetimes comparison. [Display omitted]