Fig. 18.

Typical paradigms concerning graphene combined with polymers to enhance the sensing performance of piezoresistive devices. a Schematic illustration of the mechanism for the formation of PVDF fibers coated by RGO nanosheets, followed by electrostatic interactions. b Top view of the metal letters “C,” “A” and “S” positioned over the pressure sensor array and the current map of pressure distributions. c Photograph of the device loaded on two wrists for testing blood pressure through near-surface arteries. Reproduced with permission from Ref. [128]. Copyright 2016 Elsevier Ltd. d The multifunctional E-skins attached on a hand, wrist and throat to monitor biosignals. Reproduced with permission from Ref. [50]. Copyright 2017 Elsevier Ltd.