Electrodeposition of Pd-Pt Nanocomposites on Porous GaN for Electrochemical Nitrite Sensing.

Rui Xi,Lu-Jia Wang,Chao Wang,Jing-Hui Yan,Long Zhang,Shao-Hui Zhang,Ge-Bo Pan

doi:10.3390/s19030606

Abstract

In recent years, nitrite pollution has become a subject of great concern for human lives, involving a number of fields, such as environment, food industry and biological process. However, the effective detection of nitrite is an instant demand as well as an unprecedented challenge. Here, a novel nitrite sensor was fabricated by electrochemical deposition of palladium and platinum (Pd-Pt) nanocomposites on porous gallium nitride (PGaN). The obtained Pd-Pt/PGaN sensor provides abundant electrocatalytic sites, endowing it with excellent performances for nitrite detection. The sensor also shows a low detection limit of 0.95 µM, superior linear ampere response and high sensitivity (150 µA/mM for 1 to 300 µM and 73 µA/mM for 300 to 3000 µM) for nitrite. In addition, the Pd-Pt/PGaN sensor was applied and evaluated in the determination of nitrite from the real environmental samples. The experimental results demonstrate that the sensor has good reproducibility and long-term stability. It provides a practical way for rapidly and effectively monitoring nitrite content in the practical application.

Highlights

As a typical inorganic pollutant, nitrite is closely related to pluralistic fields, such as environmental chemistry, food industry and biological process
palladium and platinum (Pd-Pt)/porous gallium nitride (PGaN): The synthesis electrodes was divided into two steps
DI water and dried with an Electrochemical nitrite detection: Nitrite detection was studied in a conventional three-electrode system using a Pd-Pt-modified PGaN (Pt/PGaN)

Summary

Introduction

As a typical inorganic pollutant, nitrite is closely related to pluralistic fields, such as environmental chemistry, food industry and biological process. Compared with other electrode materials, GaN can achieve a higher chemical and thermal stability These unique properties make it generate less noise, resulting in a low background signal. The correlation research indicated that it can be applied in some fields as an excellent electrode [19,20,21] Due to their excellent electrocatalytic activities, noble metal nanomaterials (NMs) have been applied to composite electrochemical sensors [22,23,24,25,26]. In comparison with other nanomaterials, NMs are considerably more stable under ambient conditions Their unique catalytic performances together with their decreased dimensions and high surface-to-volume ratio demonstrate enormous potentials in environmental and biological applications. The obtained Pd-Pt/PGaN sensor provided a wide linear range, lower detection limit, high selectivity and excellent stability for nitrite. The sensor exhibited a good recovery for nitrite determination in practical sample analysis

Experimental Section

Results and Discussion

Conclusion