Manufacture of titanium dioxide structures

A method for manufacturing a structure of a titanium compound selected from the group consisting of sheets, wires and tubes, the method comprising the steps of:

• performing one of:
• i) the consecutive steps a) and b) or
• ii) the step ab),
• before performing the consecutive steps c), d), and e),
• a) providing at least one titanic acid with the general formula [TiOx(OH)4-2x]n and dissolving it in an aqueous solution comprising at least one compound selected from the group consisting of TiOCl2, TiCl4, and HCl so that a clear solution is obtained, wherein the pH of the clear solution is lower than 1 after dissolution,
• b) increasing the temperature of the clear solution until reaching a temperature in the interval 68-85° C. where precipitation starts to occur, adding at least one acidic stabilizer before the precipitation starts to occur, and holding that temperature during at least 1 minute during stirring to obtain a dispersion of particles comprising TiO2 as an intermediate product,
• ab) providing a dispersion of particles comprising TiO2, wherein the average diameter of the particles in the dispersion is 3-20 nm, preferably 4-15 nm, more preferably, 4.5-7 nm, and wherein the dispersion comprises at least one alpha hydroxy acid as acidic stabilizer,
• c) adjusting the concentration of hydroxide ions in the dispersion from step b) to at least 8 M by adding an alkali metal hydroxide MOH,
• d) treating the dispersion from step c) at a temperature in the interval 90-170° C. during 6-72 hours to obtain a plurality of first structures comprising alkali metal titanate, and
• e) treating the plurality of first structures comprising alkali metal titanate to exchange at least a part of the alkali metal ions M+ with H+ to obtain a plurality of second structures comprising protonated titanate.