Enhanced photocatalytic H2O2 production using BiOCl nanosheets decorated with Pd nanoparticles and polyethyleneimine

The photocatalytic conversion of endless solar energy into storable and usable chemical energy, such as photocatalytic hydrogen peroxide production, is promising and attractive. However, a satisfactory hydrogen peroxide yield has not been achieved using photocatalysts due to the rapid recombination of photoexcited carriers and the rapid decomposition of H2O2. Herein, a polymer polyethyleneimine (PEI)-assisted Pd metal loading BiOCl nanosheet photocatalyst (Pd/PEI/BOC) is designed to achieve higher photocatalytic activity. Experimental results show that compared to the Pd/BOC catalyst with a Pd loading of only 0.26 wt%, the Pd/PEI/BOC catalyst can achieve a higher Pd loading of 0.45 wt%, which is due to the obvious shifting of the isoelectric point (IEP) of BiOCl from the pH value of 4.1 to 8.4 in the presence of PEI, leading to enhanced immobilization. Furthermore, H2O2 decomposed more slowly for the Pd/BOC catalyst modified by PEI. In addition, Pd can significantly enhance the separation of electrons–holes and light absorption range, especially for visible light. Therefore, under simulated sunlight, this Pd/PEI/BOC catalyst displayed a higher H2O2 production ability of 3700.23 μmol g−1 h−1.