fig4

Figure 4. Relationship between thickness of EDL and ion concentration and the relationship between conductance and ion concentration. (A) Relationship between thickness of EDL and the counterion density. PB is the result of the nonlinear Poisson-Boltzmann theory and LPB is the result of the linearized Poisson-Boltzmann theory. Figure reproduced with permission from Schoch and Renaud^[63] (Copyright © 2001 Elsevier). (B) Scatter line showing the change of the conductance of the nanochannels in different concentrations of KCl solution and straight line showing the conductance change of the bulk solution. Figure reproduced with permission from Wu et al.^[52] (Copyright © 2020 Elsevier). EDL: Electric double layer.