Sorption of inorganic nanoparticles in woven cellulose fabrics

Titanium dioxide was deposited from aqueous suspension onto cellulosic surfaces. Titania was sourced from Degussa (P25™, 70:30 anatase:rutile). Dry uptake of particles was shown to be rapid and dominant with one-third of the deposition occurring in less than 30 s and over one-half in the first minute. Isotherms were recorded to compare the rate of titanium deposition on dry and pre-wetted cotton. In the dry case uptake reached a maximum in 30 min whereas in the pre-wetted case the uptake was seen to continue beyond 180 min. A broad trend of higher deposition occurring at lower pH was seen, corresponding to the region where surface charges were opposite and thus attractive. Dry pickup was less significant at high pH. The response to varying ionic strength was complex and was attributed to the combined effect of charge screening, particle aggregation and consequent particle entrapment or occlusion. Titania deposition into the interstices of woven cotton sheets resulted in the formation of inorganic, nanoparticulate skeletons which could be isolated by controlled combustion of the cellulose and thus cotton was suggested to have potential for the templated synthesis of high surface area semiconductor materials.