2D MoSe₂ sheets embedded over a high surface graphene hybrid for the amperometric detection of NADH

Delaminated 2D sheets of MoSe₂ were prepared by liquid phase exfoliation and were embedded over high surface area hydrogen exfoliated graphene (HEG) by a simple technique. The MoSe₂/HEG hybrid composite exhibits fast heterogeneous electron-transfer (HET) and a high electrochemically active surface area compared to only HEG. When employed for detection of NADH, it exhibits electrooxidation at a low potential of 150 mV (vs. Ag/AgCl) with high sensitivity of 0.0814 µA⋅µM^-1⋅cm² over a wide linear range (1-280 μM), good selectivity, and a low limit of detection (1 μM). The good performance of the composite is due to the homogeneously dispersed 2D sheets of MoSe₂ over large-surface area HEG, which retain its electrochemical activity, prevents restacking, and acts as an electron transfer channel. On the basis of the above analytical requirements and its easy synthesis, the hybrid composite represents a robust material for electrochemical sensing. Graphical abstract Schematic of the 2D MoSe₂/HEG composite for electrochemical detection of NADH.