Green‐Synthesized Titanium Dioxide Nanoparticles: Current Status, Technological Advances, and Sustainable Applications

Rapid industrialization and urbanization have intensified environmental pollution, including persistent organic contaminants and toxic metals that threaten ecosystems and human health. Green‐synthesized titanium dioxide (TiO 2 ) nanoparticles (NPs) are gaining attention for their lower‐hazard reagents, reduced energy inputs, and competitive performance relative to conventional routes. This review consolidates current green synthesis strategies for TiO 2 NPs and the accompanying structure–property relationships derived from standard characterization (e.g., XRD, TEM, DLS, FTIR, UV–Vis, and BET). Applications are surveyed across three domains: (i) environmental remediation, highlighting photocatalytic degradation of pharmaceutical residues and dyes in water and the adsorption/photocatalytic removal of heavy‐metal ions; (ii) pharmaceuticals, where TiO 2 NPs act as formulation components or nanocarriers that modulate stability, release, and targeting of active ingredients; and (iii) medicine, encompassing antimicrobial surface coatings, wound‐care and implant interfaces, imaging/theranostic platforms, and photoactivated antimicrobial/anticancer interventions. This review summarizes recent advances, performance benchmarks under realistic conditions (pH, ionic strength, and real effluents), and safety/regulatory considerations related to particle size, crystal phase, dopants, and surface modification. Finally, this review identifies key gaps in scalable green synthesis with tight batch control, standardized testing in complex matrices, and life‐cycle assessment and outlines research directions to enable reproducible, safe, and application‐ready TiO 2 nanotechnology.