Label-Free Electrochemical Detection of Dibenzofuran Using MnO₂ Nanofibres

Rapid industrialization is taking a huge toll on environment. Specifically,industrial sites engaged in combustion and carbonization processes of coal-based fuels and its derivative results in the discharge of Dibenzofuran (DBF). It is considered as one of the most hazardous organic pollutants of concern by global environmental protection agencies. DBF is a Persistent, Bioaccumulate and Toxic (PBT) chemical which causes significant damage to human and surrounding environment. In this study an electrochemical sensor with the potential to be integrated with current drinking water dispensing systems to warn individuals about the presence of DBF is developed. Nanofibrous manganese dioxide (α-MnO2) is employed as receptor for the detection of DBF, while the sensing performance has been probed using electrochemical impendence spectroscopy. An equivalent electrical circuit model was developed using the electrochemical impendence data in order to gain insights into the electron transfer kinetics involved. The impedance response shows a linear relationship with DBF concentration over a range from 10
^-2
nM - 10
⁶
nM. The limit of detection and sensitivity were calculated to be 1.22 nM and 0.58 kΩ/nM/mm
²
respectively. The shelf-life of the sensor was found to be around 45 days.