In Situ Fabrication of Three-Dimensional Graphene Films on Gold Substrates with Controllable Pore Structures for High-Performance Electrochemical Sensing

hydrothermal reduction (HR), [ 13–15 ] electrochemical reduction, [ 16–18 ] and chemical vapor deposition. [ 19,20 ] Among these approaches, the HR is considered as one of the most attractive techniques, because of its simplicity, low cost, and especially the green reduction without generating any contamination, due to the simultaneous process of self-assembly and reduction of graphene oxide (GO) sheets. However, two potential problems are accompanied with the HR technique, which would limit the extensive applications of the obtained 3D graphene. One is concerned on that the pore dimensions in the framework of the proposed 3D graphene were usually around several micrometers and few hierarchical pore structures were observed, which signifi cantly restricted their surface area and impaired the availability of the surface. Another involved is that the HR approach is now confi ned in the preparation of porous graphene monolith, while the in situ fabrication of graphene fi lms on the supporting substrates is stimulated by the enormous demand in the applications of micro/nano devices, smart membranes and electrochemical sensors. [ 21–24 ] Therefore, it has remained a great challenge to fabricate novel desired 3D graphene fi lms using the HR technique. Electrochemical aptasensors have found many signifi cant applications on account of their distinctive properties of high affi nity and specifi city toward extensive targets, for example, small molecules, biological proteins and cells. [ 25–27 ] The development of promising electrode materials with novel 3D structures is considered as a critical strategy to construct an excellent electrochemical biosensor. [ 28–32 ] The huge surface area of 3D structures would improve immobilization sites for the biological molecules, provide more interfacial reaction positions and make the molecules easily accessible to electrode surface, In Situ Fabrication of Three-Dimensional Graphene Films on Gold Substrates with Controllable Pore Structures for High-Performance Electrochemical Sensing