The recombination of photo-induced charges is one of the main issues to limit the large-scale applications in photocatalysis and photoelectrocatalysis. To improve the charge separation, we fabricate a novel type II 2D ultrathin TiO2/WO3 center dot H2O heterostructures with the assistance of supercritical CO2 (SC CO2) in this work. The as-fabricated heterostructures possess high photocatalytic activity for the degradation of methyl orange(MO) and high photocurrent response under simulated solar light (AM 1.5). For the TiO2/WO3 center dot H2O heterostructures, the MO solution could be degraded by 95.5% in 150 min, and the photocurrent density reaches to 6.5 mu A cm(-2), exhibiting a significant enhancement compared with pure TiO2 and WO3 center dot H2O nanosheets. (C) 2017 Elsevier B.V. All rights reserved.