Abstract: The exceptional adsorption performance of rice husk charcoal (RHC) has attracted attention across various fields. However, its practical applications are greatly hindered by inherent limitations such as structural collapse of the pore network and poor mechanical properties. Therefore, the development of structurally robust and functional RHC through advanced technologies is of considerable significance. In this paper, rare earth elements with characteristic f-orbitals were employed as pore wall strengthening units, and RHC possessing advantages such as high porosity and high adsorptivity was adopted as the precursor material. A novel alkali-activated rice husk charcoal (ARHC) with a “beam-column structure” was then synthesized via hydrothermal alkali activation. By incorporating lanthanum（La） as the strengthening unit, a lanthanum-based biomass porous carbon material (ARHC@La) was fabricated through high-temperature hydrothermal in situ hybridization. A series of characterizations were employed for material and structural analysis to elucidate the ultrastructure of the novel ARHC@La. The results revealed that ARHC obtained a stable “beam-column” architecture where La played a crucial role in maintaining the structural integrity of the overall RHC. Currently, the elimination of excess carcinogenic malachite green (MG) from water is of critical importance to prevent water quality deterioration. Therefore, based on the novel ARHC@La, cobalt (Co) was introduced, and lanthanum-cobalt bimetallic bimetallic-doped modified RHC (ARHC@Co-La) was successfully prepared via hydrothermal alkali activation. Experimental results demonstrated that ARHC@Co-La exhibited the outstanding adsorption performance for MG, achieving an adsorption capacity of 225.331 mg·g^-1 within 30 minutes, which was of rapid-adsorption characteristic. Even after 20 consecutive adsorption-desorption cycles, the removal rate of MG retained over 80%, demonstrating its excellent regenerative stability. Batch adsorption studies indicated that the adsorption process of MG conformed to a pseudo-second-order kinetic model and the Freundlich model. Thermodynamic analysis further revealed that the adsorption process of MG was a spontaneous, exothermic, and entropy-reducing.