▎ 摘　　要

NOVELTY - Preparing self-calibrating current ratio type pH sensor involves taking carbon electrode as substrate, self- assembling the carbon nano-material on the surface of the carbon electrode, polymerizing the o- phenylenediamine on the surface of the modified electrode by in-situ electrochemistry to obtain the pH sensor. The carbon electrode is glassy carbon electrode carbon fiber electrode carbon paste electrode or screen printing electrode the carbon nano material is carbon nano tube carboxylated carbon nano tube aminated carbon nano tube graphene oxide or graphene. USE - Method for preparing self-calibrating current ratio type pH sensor. ADVANTAGE - The sensor exhibits good selectivity repeatability reproducibility stability and reversibility, has good application prospect for the actual sample in situ pH measurement.