Photoelectrochemical sensor based on carboxylated graphdiyne co-sensitized TiO2 for sensitive detection of dopamine

Abstract

As a new type of carbon material, graphdiyne (GDY) has wide application prospects in the fields of photocatalysts and photoelectrochemical detection due to its suitable energy bandwidth and high electronic conductivity. However, the highly conjugated and stable macrocyclic structure of GDY makes it difficult to be isomerized and modified on other materials. In this work, click chemistry was used to successfully carboxylate GDY so that it can be stably combined with other optoelectronic materials and some small biological molecules through chemical bonds. A composite optoelectronic material of carboxylated GDY and TiO2 was synthesized and successfully applied in the field of photoelectrochemical detection, a stable and sensitive dopamine sensor was obtained. Based on multiple signal amplification strategy, a wide linear detection range from 0.0005 mM to 1.05 mM with a low detection limit (1.36 × 10−4 mM) was obtained.