▎ 摘　　要

NOVELTY - Graphene transistor ion sensor comprises a substrate and a gate. A source electrode and a drain electrode provided on the substrate. A graphene channel is provided between the source electrode and the drain electrode. A carbon point is fixed on the surface of the grid. USE - The sensor useful for detecting the copper ion (claimed). ADVANTAGE - The sensor: is very high sensitivity; the operating voltage is lower than 1 V and can reaches the minimum detection limit of copper ions about 1014 M; and instantly changes the current of the sensor after changing the copper ion concentration. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing the graphene transistor ion sensor comprising preparing the gate, the source electrode and the drain electrode on the surface of the substrate and making a channel exist between the source electrode and the drain electrode, (ii) tiling graphene on the channel between the source electrode and drain electrode to obtain a graphene transistor and (iii) fixing the carbon point on the gate surface of the graphene transistor obtained in the step (ii).