Iron(III) nitrate nonahydrate is widely utilized in research focused on:

• Analytical Chemistry: It serves as a reagent in various analytical procedures, particularly in the determination of trace metals and other compounds through spectrophotometric methods.
• Material Science: This compound is used in the synthesis of iron oxide nanoparticles, which have applications in catalysis, magnetic materials, and drug delivery systems.
• Agriculture: It acts as a nitrogen source in fertilizers, promoting plant growth and enhancing soil nutrient content, particularly in iron-deficient soils.
• Textile Industry: Iron(III) nitrate nonahydrate is employed as a mordant in dyeing processes, improving the color fastness of fabrics and enhancing the vibrancy of dyes.
• Environmental Science: It is used in wastewater treatment processes to remove phosphates and other contaminants, contributing to cleaner water systems.