Formaldehyde detection based on tannin carbon dots

With the acceleration of industrialization, formaldehyde detection is becoming increasingly important. Numerous challenges persist about sensitivity and safety in the field of formaldehyde detection. This paper developed a formaldehyde detection material based on carbon dots, and effectively improved the sensitivity, safety and convenience of detection. Specifically, tannin acid (TA) was utilized as the carbon source and urea as the nitrogen source to prepare tannin/urea carbon dots (TA-CDs) with excellent performance. The fluorescence intensity of the carbon dot solution gradually decreased with increasing formaldehyde concentration. A significant linear relationship (R² = 0.99462) was observed in the range of 0.00015–0.035 mmol/L, with a practical formaldehyde detection limit of 0.296 μmol/L. This paper utilizes natural poly-phenol compound TA as the raw material, which boasts unique characteristics and low cost. TA-CDs prepared from it are abundant in surface defects and active sites, exhibiting significant advantages in formaldehyde detection and possessing immense application potential.