Abstract: The highly ordered porous anodic alumina ( AAO) membrane was synthesized , and using it as
template , the WO 3 ·H 2O nanowire arrays with good orientation were prepared by the sol 2 gel method. The
product s are characterized by X2ray Diff raction and XPS , Scanning Elect ron Microscopy and Specific Surface Area Inst rument . And the result s show that WO 3 ·H 2O nanowires are uniformly dist ributed , and the diameters are consistent with the pores of the AAO template , about 26 nm in diameter and 1. 1μm in length. Compared with the WO 3·H 2O film on fiberglass cloth as carrier , the WO 3 ·H 2O nanowires have a smaller crystallite size , less density and larger specific surface area. Photocatalytic activities of the WO 3 ·H 2O/ AAO and WO 3 ·H 2O/fiberglass cloth were measured by degradation of gaseous formaldehyde respectively , and the rate constant of photocatalytic reaction is about 3. 4 times that of the WO 3·H 2O/ fiberglass cloth film. It is indicated that the WO 3 ·H 2O nanowires arrays synthesized as AAO template have higher photocatalytic activity.