The photogalvanic effect (PGE) has been demonstrated to induce pure spin current in low-dimensional spintronic devices possessing spatial inversion symmetry, independent of photon energy (E_ph) or incident light polarization/phase angles (θ/φ). The electronic properties of one-dimensional systems can be effectively modulated through edge passivation, rendering them more suitable for generating pure spin current. This study employs first-principles calculations based on density functional theory combined with the non-equilibrium Green’s function method to systematically investigate zigzag graphene and silicene nanoribbons asymmetrically passivated at their edges with hydrogen and halogen atoms (F, Cl, Br). Calculations of the band structure, density of states, and magnetic moment reveal that four structures-F-2H 6ZCNR, F-2H 6ZSiNR, Cl-2H 6ZSiNR, and Br-2H 6ZSiNR-exhibit two strongly localized, fully spin-polarized (100% spin polarization) states with opposite spin orientations near the Fermi level, classifying them as bipolar spin semiconductors. Based on these structures, optoelectronic devices with spatial inversion symmetry are designed. The study shows that when the central region of the device is irradiated with linearly polarized light (LPL) or elliptically polarized light (EPL) at varying photon energies (E_ph) and incidence angles (θ/φ), photocurrents arise in both spin channels with equal magnitude but opposite directions, provided the photon energy exceeds the spin band gap. Consequently, the total charge current remains zero while a finite spin current persists, confirming the successful generation of pure spin current. Notably, this pure spin current is independent of the light polarization type, E_ph, and θ/φ. Further analysis of the spin density distribution, band structure, and spatial inversion symmetry elucidates the physical mechanism responsible for pure spin current generation. The robustness of this effect stems from the intrinsic bipolar spin states and the spatial inversion symmetry of the device. These findings not only provide a theoretical foundation for achieving pure spin current in one-dimensional graphene and silicene nanoribbons but also offer a promising strategy for advancing next-generation spintronic devices, quantum computing, and nanosensing technologies.