Precious metal nanomaterial-modified electrochemical sensors for nitrite detection

Nitrite exists in the natural environment widely and is often used in human daily life. It causes varying degrees of harm to the water ecosystem and human health when the nitrite concentration exceeds the standard. Therefore, it is necessary to develop reliable nitrite detection methods. Compared with others, the electrochemical method for detecting nitrite has a series of advantages such as easier, lower cost, and faster analysis. The present research on the detection of nitrite by electrochemical methods focuses on the modification of electrodes. Numerous studies have shown that the addition of precious metals can increase the electronic transfer rate and the electrocatalytic active sites of the electrode, significantly improving the catalytic oxidation ability of the modified electrode for nitrite. This article reviews the research progress of precious metals (Au, Pd, Ag, Pt) in the preparation of nitrite electrochemical sensors in the past 10 years, including the application of single metal nanomaterials and bimetal or alloy materials. The performance and advantages of precious metal nanomaterials in the development of nitrite electrochemical sensors are discussed in detail. The challenges and application prospects of precious metal nanomaterials applied to nitrite electrochemical sensing platforms are proposed.Graphical abstract