Optical modes enhance solar water splitting in one-dimensional plasmonic particle grating

Solar energy conversion to green energy production via solar water splitting, imitates photoinduced charge transfer into water or an electrolyte using a photoelectrode. Bandgap limitation affects common semiconductors used as photoelectrodes. From that perspective, interband and nonradiative decay of plasmon resonance facilitates a plasmonic phenomenon with a more comprehensive spectrum performance. This work systematically studies photoelectrochemical current generation using plasmonic Gold Nanoparticles (GNPs) organized in a one-dimensional lattice. Such arrangement of plasmonic GNPs produced photonic effects such as guided mode resonance and grating-coupled surface plasmon resonance, which contributed to superior photoelectrochemical current production than metal bar grating, and random gold nanoparticles. Additionally, a semiconductor layer was deposited over the grating of plasmonic particles to enhance plasmonic charge collection and current generation and extended the UV-limited semiconductor's PEC spectral response bolstered by multiphotonic-plasmonic resonance phenomena. Our research offers a derived approach to enable light harvesting mechanisms for the production of green energy.