Novel hierarchical molybdenum-polydopamine nanocarriers (SMPDA) for hosting the inhibitors in the redesigned molybdenum-polydopamine-Zn2+ (SMPDA@Zn) form were utilized in the epoxy-based (EP) coating formulation to reinforce the barrier / self-healing functions. In the present study advanced FTIR, Raman, XRD, FESEM-EDS, MAP, TEM, BET, ICP-OES, EIS, PDP, OCP, salt spray, cathodic delamination, and pull-off appraisals techniques were employed to assess the influence of hierarchical nanocarriers in the solution and active / passive properties of epoxy coatings. The conspicuous impermeable hybrid films composed of Fe2+/3+-MoO42−, Fe2+/3+-polydopamine, Fe2+/3+-MoO42−-polydopamine and ZnO / Zn(OH)2 on active sites of mild steel in a saline solution comprising the SMPDA@Zn and SMPDA extract would supply %80 and %57 inhibition efficiency, respectively. Active corrosion protection in reference to Rtotal (Rct + Rf) 44463.1, 41879.3, and 9176.3 KΩ cm2 after 72 h immersion for composite and conventional EP coatings by plugging the polymeric film pores as well as healing the defects, intentionally created on the surface were enhanced interestingly up to 4.8 and 4.5 times. The superiority of the incorporated coatings was also obvious in the pull-off and cathodic disbanding tests so a delamination area reduction of %73 was recorded in the presence of the hierarchical nanocarriers. The present study illuminated new horizons in materials science and engineering on the potential usage of durable self-healing primer epoxy-based EPSZ and EPSM coatings in assorted industries like oil and gas pipelines, marine, and offshore infrastructure industries, refineries, petrochemical plants, non-renewable power plants, sheet metal working of shipbuilding, and subsea equipment.