An Ultra‐Sensitive Electrochemical Sensor for Nitrite Based on Green Synthesized Gold Nanoparticles Using Colocasia Esculenta Extract

Abstract Seeking to establish a novel, eco‐friendly and ultra‐ sensitive electrochemical nitrite sensor, we have fabricated fluorine doped tin oxide (FTO) electrode with green synthesized gold nanoparticles (AuNPs) from gold salt and taro plant (Colocasia esculenta) extract (Taro_AuNPs/FTO). Different morphological and elemental analysis were conducted to undermine morphological condition and shapes of AuNPs. Further, electrochemical studies were performed for enabling observation on the modification as well as interaction between nitrite ion and AuNPs on the modified FTO. Furthermore, the performance of Taro_AuNPs/FTO sensor was evaluated using DPV technique and the limit of detection (LOD) was 0.923 nmol L⁻¹ (S/N=3) having sensitivity of 0.00503 μA mM⁻¹ cm⁻² within 5–500 μmol L⁻¹. Additionally, an insightful mechanistic overview was highlighted about interacting nitrite on the modified electrode surface. Finally, interference test, stability, reproducibility and real sample analysis were conducted to establish the effectiveness of Taro_AuNPs/FTO electrochemical senor for environmental application.