Three brands of zero-valent iron nanoparticles (Fe degrees NPs) were biologically/chemically fabricated, and sorption capacities thereof in crystal violet (CV) water remediation were compared and contrasted. Meanwhile, the beta-Cyclodextrin (beta CD) amounts effects on the size and structure of Fe degrees NPs were evaluated via field emission scanning electron microscopy, elemental mapping, X-ray diffraction, transmission electron microscopy, Brunauer-Emmett-Teller, and zeta potential analyses. Separated spherical ultra-small Fe degrees NPs (6.1 nm) with a narrower size distribution could be produced at higher dosages of beta CD. The green synthesized Fe NPs showed better performance than those produced chemically in CV removal (39.5% vs. 14.7%, respectively) because of their higher surface area (46.68 m(2)/g vs. 34.38 m(2)/g, respectively). beta CD functionalized Fe degrees NPs could double nanoadsorbent proficiency in CV removal (99.8%), possibly because of simultaneous decrement in the nano particles sizes and increment in the active sorption sites of nanoadsorbent. The effects of nanoadsorbent amount, pH, contact time, temperature, and initial concentration on the sorption were all scrutinized. The adsorption kinetics were found to be finely fitted with the pseudo-second-order model. Adsorption capacity calculated by Langmuir model was 454.5 mg/g (20 degrees C, at pH 9.0). The current green, reusable, and low-cost nanoadsorbent could be utilized proficiently for practical water remediation.