Superconductivity emerging from an electronic phase separation in the charge ordered phase of RbFe2As2

As-75, Rb-87, and Rb-85 nuclear quadrupole resonance (NQR) and Rb-87 nuclear magnetic resonance measurements in a RbFe2As2 iron-based superconductor are presented. We observe a marked broadening of the As-75 NQR spectrum below T-0 similar or equal to 140 K which is associated with the onset of a charge order in the FeAs planes. Below T-0 we observe a power-law decrease in the As-75 nuclear spin-lattice relaxation rate down to T* similar or equal to 20 K. Below T* the nuclei start to probe different dynamics owing to the different local electronic configurations induced by the charge order. A fraction of the nuclei probes spin dynamics associated with electrons approaching a localization while another fraction probes activated dynamics possibly associated with a pseudogap. These different trends are discussed in light of an orbital selective behavior expected for the electronic correlations.