With respect to the neat (as prepared) films, in-plane line-cuts from exposed and redoped film GISAXS scattering patterns both displayed an increase in intensity of the scattering feature and a shift to higher q-vector (Figure ). The intensity increase due to exposure is ascribed to larger electron density contrast between the crystalline nanofibrillar domains and the inter-fibrillar voids/domains arising from inhomogeneous uptake of ions into the film (Figure ). From ex situ XRF, it is apparent that significant amount of charge balanced anion-cation pairs enters the film, which presumably reside in inter-fibrillar voids/domains. Additionally, ex situ XRF revealed that excess anions also enter the film, (as the equilibrium degree of doping in pH neutral electrolyte is higher than as prepared), and these dopant anions are expected to reside within the nanofibrils to compensate the enhanced hole density. Thus we tentatively interprets the shift to higher q-vector as reflecting a shrinking of the inter-fibrillar voids/domains as the crystalline nanofibrils expand.