Bio-inspired three-dimensional micro-nanoporous graphene for constructing Schottky junction and remarkably enhanced electrochemical detection

A facile and one-step transformation towards graphene using nickel foams as the substrate into a contact between semiconducting graphene (SG) and metal is developed for fabricating a SG/Ni Schottky junction. Graphene quantum dots were cut away via the electrochemical redox method and porous three-dimensional graphene with a bandgap was generated due to the abundant defects and dangling bonds . The constructed Schottky junction is the inner drives of accelerating charge transfer and thus results in significantly enhanced electrocatalytic effect. Bio-inspired porous graphene integrates micro-nano pores and functional groups, which greatly benefits to molecules separation and specific electrocatalysis . Macroscopic pores and numerous nanopores serve as “highways” for the rapid mass transport. Massive defects and rich dangling bonds act as “perceptrons” to reflect the charge distribution change. As a successful demonstration, the fabricated SG/Ni Schottky junction exhibits appreciable electro-oxidation towards H 2 O 2 with an ultrahigh sensitivity of 4838 μA mM −1  cm -2 and an ultralow detection limit of 20 nM. This study puts forward an easy and practicable strategy to construct a Schottky junction, which is promisingly applied in other electrochemical research.