Anthracene-decorated TiO thin films with the enhanced photoelectrochemical performance.

New insight of introducing new organic compounds for the efficient photogenerated charge separation is vitally important for the current solar energy conversion. Herein, (2Z,2'Z)-4,4'-(anthracene-2,6-diylbis(azanediyl))bis(4-oxobut-2-enoic acid) (ADA)/TiO composite thin film is fabricated through the wet-impregnation strategy, which exhibits excellent photoelectrochemical performance (PEC). A combined study of ultraviolet-visible absorption spectra, scanning Kelvin probe maps, electrochemical and photoelectrochemical measurements reveals that the ADA/TiO composite with narrow bandgap of 2.42 eV extends the photo response to the visible light region. The photocurrent generated by the optimal ADA/TiO is 2.5 times higher than that of the pristine TiO. The result is attributed to the broader light absorption range and the separation of photoelectrons and holes prompted by ADA. Moreover, the high stability of the ADA/TiO composite favors the practical application. The present work may offer a promising strategy for the low-cost PEC cell in the clean solar hydrogen production.