TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Composition: The transition metal oxide includes ( alpha )-iron(III) oxide, ( gamma )-iron(III) oxide, iron oxide (Fe3O4), molybdenum trioxide, nickel oxide, copper oxide or cobalt oxide (Co3O4), preferably iron oxide (Fe3O4), molybdenum trioxide, nickel oxide, copper oxide or cobalt oxide (Co3O4). The transition metal ion-containing compound is iron(II) acetate, iron(III) nitrate, iron(III) acetylacetonate, iron(III) chloride or iron(II) oxalate, preferably iron (II) acetate, iron (II) oxalate, iron (III) acetylacetonate, iron chloride, molybdophosphoric acid, ammonium molybdate, nickel acetate, nickel nitrate, nickel chloride, copper acetate, copper nitrate, copper chloride, cobalt acetate, cobalt nitrate or cobalt chloride. The mesoporous nanostructured transition metal oxide particles comprise transition metal oxide crystal. The transition metal oxide crystal is ( alpha )-iron(III) oxide rhombohedral crystal, ( gamma )-iron(III) oxide cubic spinel crystal and/or iron oxide (Fe3O4) cubic spinel crystal. Preferred Properties: The mesoporous nanostructured transition metal oxide particles have particle size of 3-200 nm and pore size of 3-30 nm. Preferred Process: During preparation of mesoporous nanostructured transition metal oxide particles, the nanostructured transition metal oxide powder is calcined at 100-800 degrees C (preferably, 400-550 degrees C) for 1-6 hours, to obtain mesoporous nanostructured transition metal oxide particles. The pH of the transition metal ion-containing mixture is optionally adjusted to 7-11, preferably 8-10.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Composition: The soft-template compound is dodecyltrimethylammonium bromide, cetyltrimethylammonium bromide, octadecyltrimethylammonium bromide, tetradecyltrimethylammonium bromide, decyltrimethylammonium bromide, octyltrimethylammonium bromide or Pluronic F-127 (RTM: poloxamer), preferably octyl trimethylammonium bromide, dodecyltrimethylammonium bromide or cetyltrimethylammonium bromide. The solvent is mixture of ethanol and water. The weight ratio of ethanol and water in solvent is 1:1-4:1, preferably 1:1-3:1.