SYNTHESIS AND CHARACTERISATION OF HYBRID NANO FE-NPK FERTILIZER FOR ENHANCED NUTRIENT UPTAKE IN PLANTS

Abstract

Nanotechnology offers innovative solutions to the limitations of conventional fertilizers, particularly regarding nutrient availability and uptake efficiency. This study presents the synthesis and characterization of a hybrid nano Fe-NPK fertilizer designed to address iron deficiency and enhance nutrient absorption. The fertilizer was prepared by thermally reacting calcium phosphate, potassium chloride, and urea, combined with nano-iron synthesized via chemical reduction of iron(III) tetraoxosulfate heptahydrate using sodium borohydride. The final formulation achieved an optimized nutrient ratio of 1:2:1:2 (N:P:K:Fe). Characterization techniques including AAS, EDS, XRD, FTIR, UV-Vis, and SEM were employed to verify composition and structure. AAS confirmed elemental presence, while EDS revealed uniform iron distribution. XRD patterns showed peaks at 2θ = 26°, 37°, and 48°, indicating iron oxide phases. FTIR peaks at 1429.20 cm⁻¹ and 3481.60 cm⁻¹ suggested carbonyl and amine functional groups, and UV-Vis absorption at 210 nm and 350 nm further validated the presence of iron and amine species. SEM imaging revealed a core-shell morphology typical of nanostructured materials. The successful synthesis and structural integrity of the nano Fe-NPK fertilizer highlight its potential for improving iron bioavailability and nutrient uptake in crops, representing a step forward in sustainable metallo-agriculture.