Ionic imprinting polymer as a “suit of armor” to boost photostability of CdS in photocatalytic overall water splitting

Photocorrosion significantly undermines the efficiency of CdS-based photocatalysts in photocatalytic applications. This research introduces a pioneering solution by encapsulating CdS nanorods with an ion-imprinted polymer (IIP) layer, serving as a "suit of armor" to inhibit its photocorrosion in photocatalytic overall water splitting. This innovative IIP coating not only shields the CdS from direct exposure to oxygen and water, thereby substantially reducing photocorrosion and enhancing stability, but also augments the separation efficiency of photogenerated charge carriers. It is found that, without any sacrificial agent, CdS-IIP sample exhibits superior photo responsiveness and durability compared to untreated CdS, and both H2 gas and H2O2 are detected during the overall water splitting process. Impressively, after approximately 80 h of exposure to simulated sunlight, CdS-IIP still maintains robust photocatalytic activity, achieving an average hydrogen production rate of 69.84 µmol g-1h−1, approximately 15 times higher than that of pure CdS. These findings offer valuable insights into enhancing the stability and efficiency of CdS-based photocatalysts.