Construction of electrochemical sensing interface towards Cd(II) based on activated g-CN nanosheets: considering the effects of exfoliation and protonation treatment.

There is an urgent need to construct highly selective low-cost sensors for fast detection of toxic metal ions such as cadmium. When compared with 3D bulk materials, 2D layered materials after activation treatments show superior performances for electrochemical metal ion detection. The bulk graphitic carbon nitride (hereafter b-g-CN) was prepared by thermal polymerization with urea as a precursor; it was then activated through ultrasonic liquid exfoliation and protonation which resulted in successful fabrication of activated ultrathin g-CN nanosheets (hereafter a-g-CN).