Hemispherical and columnar TiO2 array were produced by reactive pulsed laser deposition (PLD) using self‐assembled polystyrene (PS) monolayers as templates. The integration of PS
microspheres self‐assembly processes and PLD permits the creation of periodic arrays in hexagonal arrangement. The micro/nano array architecture demonstrates outstanding catalytic performance in the degradation of methylene blue dye in aqueous solution. The obtained
results suggest that besides other structural characteristics the large specific surface area plays an essential role in the improvement of photoactivity of oxide semiconductor catalyst.