Sp2-rich dendrite-like carbon nanowalls as effective electrode for environmental monitoring of explosive nitroaromatic

Abstract

Nitroaromatic compounds are commonly used explosive materials that pose a risk to human health and ecosystems due to their acute toxicity and carcinogenicity. Nitroaromatics have numerous pathways into the environment via discarded munitions (e.g. into the Baltic Sea after World War II), after use in mining operations, and in industrial run-off from factories producing these compounds (which are produced across the world to date). The current detection method relies on chromatography and mass spectrometry methods, which are time-consuming, expensive, and require specialist equipment and training. Carbon-based electrochemical sensors offer a low-cost, fast, and easy on-site method for the detection of a variety of compounds. This study demonstrates an efficient approach for rapid electrochemical sensing of Tetryl (N-methyl-N-2,4,6-tetranitroaniline) through the use of boron-doped sp2-rich carbon structures. These structures, known as dendrite-like carbon nanowalls (D:CNW), were fabricated in one-step deposition and extensively characterized to understand the structure and surface chemistry. Electrodes were used to detect a range of nitroaromatic compounds, most notably tetryl in both laboratory and real environmental samples, with an excellent sensitivity of 153.0 µA cm−2 ppm−1 and a detection limit of 17 ppb. The analytical and electrochemical capabilities of D:CNW electrodes indicate their suitability for extensive environmental monitoring.