Computational simulation of graphene/h-BN nanopores for single-molecule herbicide sensing

The growing world population and climate change are key drivers for the increasing pursuit of more efficient and environmentally-safe food production. In this scenario, the large scale use of herbicides demands the development of new technologies to control and monitor the application of these compounds, due to their severe environmental and health-related problems. Motivated by these issues, in this work, a hybrid graphene/boron nitride nanopore is explored to detect/identify herbicide molecules (Glyphosate, aminomethylphosphonic acid, Diuron, and 2,4D). Solid-state nanopores based on 2D materials have been widely explored as novel generation sensors capable of single-molecule resolution. The present investigation combines density functional theory (DFT) and the non-equilibrium Green's function method to assess the interaction of each herbicide with the nanopore and how its interaction modulates the device's electronic transport properties. The device's sensitivity spreads from 9.0% up to 27.0% when probed at different gate voltages. Overall, the proposed device seems to be sensitive and selective to be considered as a promising single-molecule herbicide sensor.