Sea-Urchin-Like Bi2S3 Microstructures Decorated with Graphitic Carbon Nitride Nanosheets for Use in Food Preservation

Although nitrite (NO2–) is listed as a poisonous inorganic pollutant that is dangerous to humans and other creatures, it is widely used in food preservatives and agricultural products. It is frequently detected in many foods, water, environmental systems, and biological samples. In recent times, many techniques for detecting and monitoring NO2– have been proposed. Among them, the electrochemical method has been receiving particular attention due to its ease of operation. At the same time, nanocrystals of metal sulfide materials have gained the attention of researchers due to a wide range of materials with efficiently tunable properties. This article presents a rational hydrothermal approach to the synthesis of size- and morphology-controlled hierarchically grown bismuth sulfide (Bi2S3) nanorods. Changes are made to the prime parameter; temperature yields the g-C3N4 nanosheets covered on the sea-urchin-like structure of Bi2S3 nanorods. The textural characteristics, surface morphology, and chemical compositions of g-C3N4/Bi2S3 have been studied using a selection of spectroscopic methods. Accordingly, the produced catalysts were examined to detect the electrochemically active NO2–. The g-C3N4/Bi2S3-modified electrode attained a broad linear range (0.001–385.4 μM) and a higher sensitivity with a lower detection limit (0.4 nM). Therefore, g-C3N4/Bi2S3 hierarchically grown through the hydrothermal route could be a promising sensing platform to determine NO2– in real-time.