Electronic and work function-based glucose sensors on graphene, silicene, and germanene sheets – DFT studies

Abstract

Diabetes is a chronic health condition caused due to a metabolic disorder that results in high blood sugar levels. Diabetes would be the seventh-prominent reason for mortality according to recent studies. There is a need for the improvement of selective and sensitive glucose detection in medicine, clinical diagnostics, and the food industry. We have studied a density functional theory (DFT) method of the adsorption of glucose on pure graphene, silicene, and germanene sheets. For the above-mentioned structures the optimized geometries adsorption energies have been calculated to analyze the suitability and efficiency for glucose sensing. The electronic properties such as charge transfer analysis, band gap, fermi energy, work function, and density of states have been studied into attention. Our result reveals that the interaction between glucose with pristine graphene sheet is strong chemisorption when compared to the case of pristine silicene and pure germanene which exhibits weak chemisorption suitable for sensors. However pristine germanene shows high bandgap variation when compared to silicene indicating that it can act as an electronic sensor. Tomodify the adsorption properties by improving its chemical reactivity and electronic structure, we suggest either doping with different atoms, preparing sheets with defects or chemical functionalization have to be applied.