Highly Efficient Photocatalytic Hydrogen Evolution Using a Self-Assembled Octupolar Molecular System

A highly efficient photocatalytic hydrogen evolution system was prepared by using an octupolar molecule as a building block of self-assembled nanoparticles. The photocatalytic system showed an enhanced hydrogen evolution reaction (HER) rate upon the addition of halide ions, which was attributed to an external heavy atom effect enhancing intersystem crossing. The HER rate of the photocatalytic system was proportional to the atomic weight and concentration of halide ion additives, and its maximum HER rate reached 460 mmol/g.h in the presence of iodide ions and a metal co-catalyst. Further, the photocatalytic system without any halide ion additives generated hydrogen gas utilizing seawater and stimulated sunlight with remarkable efficiency (apparent quantum yield similar to 3.8%).

Automated summary

A highly efficient photocatalytic system for hydrogen evolution was developed using self-assembled nanoparticles based on an octupolar molecule. The addition of halide ions improved the rate of hydrogen evolution reaction due to the external heavy atom effect enhancing intersystem crossing. The highest hydrogen evolution rate of the system reached 460 mmol/g.h with the presence of iodide ions and a metal co-catalyst. Moreover, the photocatalytic system without any halide ion additives showed remarkable efficiency in hydrogen generation from seawater using stimulated sunlight (apparent quantum yield of about 3.8%).