Herein, a facile and effective dilution polymerization route was adopted to prepare microscale hierarchical PANI@BN nanohybrids with a surface textured similar to that of the aloe vera leaf. Synthesized samples were characterized by FTIR, XRD, FESEM, HRTEM, UV-visible absorption, and TGA/DTG. The hydrophobic nanohybrids with extremely rough surface offered a high barrier for moisture and corrosive environments. Potentiodynamic polarization measurement of PANI@BN/PVA coated steel showed the large shifting in corrosion potential to the anodic region with respect to PANI/PVA. The corrosion inhibition efficiency (IE%) of PANT@ BN/PVA coating on mild steel in 3.5 wt % of NaCl, 1 M HCl, and 1 M H2SO4 was calculated from the respective Tafel plots. The mechanistic investigation of anticorrosion performance was carried out through EIS analysis. The higher IE% of the synthesized nanohybrids with PVA coating formulation indicated that the superior anticorrosion performance on mild steel was due to synergetic effect between PANI and BN nanoparticles.