Hierarchical self-assembly of double structured Prussian blue film for highly sensitive biosensors

The morphology of a functional film, especially in the microscale or nanoscale, has been found to be critical for the performance of sensor materials. In this report, two shapes of PB crystals, microcubes and nanomastoids, were simultaneously formed using a self-assembly approach, induced by a weak electric field. This architecture exhibited an ultra-sensitive response in H₂O₂ detection (1922.3 mA M^-1 cm^-2). By consideration of the experimental results, a synergistic transmitting mechanism is provided to account for this high sensitivity, or the microcubes can fulfil the role of electron accumulation in electrocatalysis, and nanomastoids will fulfil the role of the main transport of electrons from the film to the Pt surface.