<p>Reducing Na₂O in alumina from the Bayer process remarkably improves the performance of alumina-bearing materials and efficiency of aluminum electrolysis. In this work, a novel approach of significantly reducing soda content of gibbsite with high precipitation efficiency was provided. High density of H and O and adsorption energy on (001) and (100) planes favored their preferential nucleation and growth in the seeded precipitation. High temperature reduced soda content of gibbsite, and 57% precipitation efficiency was achieved at 75&#xa0;°C. In addition to reduce ultrafine flaky particles, elevating initial temperature and high precipitation efficiency promoted growth of (101) and (112) planes but restrained exposures of (001) planes. Furthermore, the atomic ratio of Na/Al on the (100), (110), (101), and (001) planes was greater than that on (112) plane of gibbsite. High soda content on (001), (100), and (110) planes and the minimal soda content on (112) were then found. Furthermore, high Na/Al ratio also occurred at defects of kink, step, growth hillock, and the ultrafine particles. Therefore, high precipitation efficiency, high diffusion coefficient, oriented growth of gibbsite planes, and reducing defects of gibbsite were collectively adopted to reduce soda content of gibbsite. A 0.14 wt.% Na₂O in the coarse gibbsite was, thus, achieved with 56% precipitation efficiency at the initial temperature of 85&#xa0;°C for 48&#xa0;h. The results provide a promising approach to reducing soda content in alumina with high productivity.</p> Graphical Abstract <p></p>