Relationship between in-situ analysis of surface ion concentration at the photoelectrode and hydrogen production during photoelectrocatalytic reactions

Hydrogen energy is a renewable clean energy source with strong potential, which comes from a wide range of sources and produces no pollutants during the combustion process. Photoelectrocatalytic (PEC) hydrogen production utilizes solar energy as the main energy for photoelectrochemical reaction to produce hydrogen, which is green and environmentally friendly. Most of performance tests of PEC hydrogen production systems still remain on the overall performance test, neglecting the influence of microscopic particles with different positions and different concentrations on the surface of the photocatalytic membrane on the hydrogen production performance. Here, we use surface plasmon resonance tilted fiber Bragg grating (SPR-TFBG) sensors, fiber Bragg grating hydrogen (H-FBG) sensors, and fiber Bragg grating temperature (T-FBG) sensors for real-time in-situ monitoring of surface ion concentrations, hydrogen concentrations, and temperatures at different locations on the surface of the photoelectrode of a PEC hydrogen production system. A positive correlation was found between the ion concentration on the photoelectrode surface and the amount of hydrogen production, which indicates that real-time monitoring of the ion concentration on the surface of the photo-electrode can effectively reflect the performance of hydrogen production at different locations on the surface of the photoelectrode.