Fig. 6: Various applications of electrical double layers on graphene.
a–c Energy harvesting by generating a drawing potential at electrolyte-graphene interfaces. a Schematic diagram of an energy harvester composed of an electrolyte droplet sandwiched by graphene and a SiO2/Si wafer. b Formation of pseudocapacitors on graphene under static (upper) and dynamic (bottom) conditions. c Electricity generation, which is proportional to the velocity of electrolyte droplets58. d, e Flow rate and ionic concentration sensor of a six-channel graphene FET in ionic solution. d Schematic illustration of the varied ionic distribution in channels A and B due to streaming potential entrained by liquid flow. e Streaming potential difference between channels A and B as a function of flow rate and ionic concentration. f, g Biomolecule sensors based on solution-gated graphene transistors64. f Schematic diagram of the electrochemical reaction between dopamine and graphene, resulting in changes in the EDL potential distribution. g Source/drain current measurement as a function of dopamine concentration. Note that only 1 nM dopamine is sufficient for generating a different channel response65. a–c Republished with permission of Springer Nature from Yin et al.58, permission conveyed through the Copyright Clearance Center, Inc. d, e Reprinted (adapted) with permission from Newaz et al.64, Copyright (2012) from the American Chemical Society64. f, g Republished with permission of John Wiley and Sons from Zhang et al.65, permission conveyed through the Copyright Clearance Center, Inc.
