review on the synthesis of doped tio2 nanomaterials by sol-gel method and description of experimental techniques

Tio2-based nanomaterials are very effective for water and air purification and act as good antibacterialagents due to their unique physicochemical properties. tio2 is a promising nanocatalyst because of itsnon-toxicity, chemical stability, and low cost. the wide band gap and rapid electron-hole recombinationlimit its performance which can be overcome by doping with metals and non-metal ions. metal dopingimproves the trapping of electrons to inhibit electron-hole recombination and non-metal doping reducesthe bandgap of tio2. these doped tio2 materials can be synthesized by different routes like the sol-gelmethod, hydrothermal method, precipitation method, impregnation method, etc. among these, the solgelmethod is reported as the best and most accurate for the synthesis of tio2 particles in the nano scalerange. because it allows the incorporation of dopant ions at the molecular level with homogeneity and highchemical purity. the structural, morphological, and optical properties of as-synthesized tio2 nanocatalystscan be well characterized by xrd, sem, edx, ft-ir, uv vis-drs, tem, bet, and pl. in this review article,we would like to discuss the advantage of the sol-gel method over other preparative methods of tio2nanomaterials and experimental techniques related to their characterization.