A cadmium ion-selective electrode based on carbon nanotubes and polypyrene composites

Cadmium ion (Cd 2+ ) is a highly toxic and non-degradable heavy metal ion that is widely found in nature and undermines human health at a fundamental level. In this paper, an all-solid-state cadmium ion-selective electrode is developed based on multi-walled carbon nanotubes (MWCNT) and polypyrrole (PPY) composites as an intermediate layer. This electrode was applied to detect Cd 2+ , and the detection results indicate that it shows excellent Nernst response in the concentration range of 10 −7 ∼10 −3 M, the response sensitivity is 29.3 mV/decade, the detection threshold can be up to 1.0 × 10 −7 M, the response time is short (<10 s), and it has an excellent anti-interference ability for common ions (such as Na + , K + , Ca 2+ , Mg 2+ , etc.).