3D Porous Graphene\nArchitecture Integrated with Cu<sub>2</sub>O for Enhanced Electrochemical\nSensing Performance

Construction and functionalization of a 3D graphene architecture\nare crucial to harness and extend the unique features of graphene\nand thus essential for its numerous conventional and novel applications.\nHerein, a 3D honeycomb-patterned porous graphene architecture is constructed\nthrough a facile and low-cost self-assembly process and then integrated\nwith Cu<sub>2</sub>O nanoparticles via a simple electrodeposition\nprocedure. The 3D porous graphene structure is prepared by the breath\nfigure method using a graphene oxide (GO)-based complex in which GO\nis modified by a surfactant as the casting material. Benefiting from\nthe intercalation of the surfactant between the GO nanosheets and\nthe fabrication of a 3D porous structure, the aggregation inhibition\nof GO nanosheets and increases in accessible surface area are realized\nat both nano- and microscales, resulting in good electrochemical performance.\nMoreover, the deposition of Cu<sub>2</sub>O nanoparticles can further\nimprove the electrochemical sensing performance of the porous reduced\ngraphene oxide (rGO) structure. Extremely low detection limit (30.72\nnM) with a linear range of 0 μM to 30 μM, excellent anti-interference,\nrepeatability, reproducibility, stability, and high accuracy for actual\nsample testing are shown when the 3D porous Cu<sub>2</sub>O/rGO film\nis applied as an electrochemical sensor for DA detection. This work\nprovides not only a superior electrochemical biosensor but also a\nsimple, yet effective and general strategy for the construction and\nfunctionalization of a 3D graphene structure.