Magnetic Field-Assisted Photoelectrochemical Water Splitting: The Photoelectrodes Have Weaker Nonradiative Recombination of Carrier

The manipulation of photoelectrodes’ electron–hole pairs toward low recombination is the fundamental strategy to achieve high solar-to-hydrogen conversion efficiency in photoelectrochemical (PEC) water splitting cells. Herein, we demonstrate that a magnet placed parallel to a photoelectrode can improve the water splitting activity of typical BiVO4 and α-Fe2O3 photoanodes as well as Cu2O/CuO and p-Si(111) photocathodes by restraining the nonradiative recombination of their carrier. Our investigations indicate that magnetic field-assisted PEC water splitting is a more effective approach than the conventional PEC water splitting. Magnetic field assistance provides a new, effective, and general strategy to improve the activity of photoelectrodes for solar water splitting and the other PEC reactions.