TiO@SnO nanorods vertically aligned on carbon fiber papers for enhanced photoelectrochemical performance.

Semiconductor heterostructures are regarded as an efficient way to improve the photocurrent in photoelectrochemical cell-type (PEC) photodetectors. To better utilize solar energy, TiO@SnO arrays vertically aligned on carbon fiber papers were synthesized a hydrothermal route with a two-step method and used as photoanodes in a self-powered photoelectrochemical cell-type (PEC) photodetector under visible light. TiO@SnO heterostructures exhibit a stable photocurrent of 180 μA, which is a 4-fold increase with respect to that of the SnO nanoflakes on carbon paper, and a two-order increase with respect to that of the TiO NRs arrays. The evolution of hydrogen according to the photo-catalytic water-splitting process showed that SnO/TiO heterostructures have a good photocatalytic hydrogen evolution activity with the rate of 5.23 μmol h, which is significantly larger than that of SnO nanoflakes (0.40 μmol h) and TiO nanorods (1.13 μmol h). Furthermore, the mechanism behind this was discussed. The detector has reproducible and flexible properties, as well as an enhanced photosensitive performance.