| abstract |
The invention discloses an ultralow concentration electrochemical formaldehyde sensor which can detect low concentration of 10 ppb, and comprises at least a working electrode, a compensating electrode and a counter electrode, wherein the compensating electrode and the working electrode are positioned on the same working surface and isolated in different spaces, and the space where the compensating electrode is positioned comprises a compensating electrode filter layer for selectively removing formaldehyde. Provided with the parallel compensating electrode which is unlimitedly consistent with the working electrode in characteristic, the formaldehyde sensor eliminates the influence of interference gas and also eliminates a formaldehyde detection error caused by environmental temperature or humidity change, and thereby overcoming the difficulty of low resolving capability caused by too many interference factors when a traditional electrochemical sensor detects low concentration formaldehyde and having low detectability and high selectivity. The sensor also overcomes the defects of complicated operation and incapability of continuous measurement of existing products in markets. |