Self-assembly of triptycene-based polymer on cadmium sulfide nanorod to construct core-shell nanostructure for efficient visible-light-driven photocatalytic H2 evolution

Triptycene covalent polymer (TCP) was fabricated with CdS nanorod to form a novel core-shell nanorod CdS@TCP via a facile in-situ synthesis. A 7 nm thick shell composed of amorphous TCP was homogeneously anchored on the surface of CdS-NR by a self-assembly process, yielding a one-dimensional heterostructure. Characterizations exhibit that CdS@TCP with high surface area can provide abundant surface active sites and intimate contact interfaces for absorbing H2O molecules. The CdS@TCP core-shell nanocomposite as a non-noble metal photocatalyst shows significantly enhanced photocatalytic H-2 production activity and excellent photo-stability. The CdS@TCP-4 indicates the highest photocatalytic H-2 evolution rate of 104.51 mmol h(-1) g(-1), which is approximately 16.2 times than that of pure CdS-NR. Besides, the photoelectrochemical performances of CdS@TCP are measured by using transient photocurrent response, EIS Nyquist plots, open circuit potential as well as Mott-Schottky plots. The improved visible light photocatalytic H-2 evolution performance of CdS@TCP is due to its large surface area, and the formation of intimate coaxial heterojunction with n-n type, which can broaden light absorption range, boost the transfer of photoexcited charge carriers, and suppress the photo-corrosion of CdS-NR.