“…Thinking outside the box strategies, such as ultrasound and magnetic field-assisted water splitting, are promising in the OER field. , In Nature, cyanobacteria, algae, and plants utilize a similar oxygen-evolving complex (OEC). − This biocatalyst is situated in Photosystem II, a membrane-protein complex that functions as a light-driven water oxidase in oxygenic photosynthesis. − The biological OEC, an Mn–Ca cluster, oxidizes water with a notably low overpotential (20 mV) and a high turnover frequency, releasing 25–90 molecules of O 2 per second. , According to a mechanism widely accepted by Kok, OEC can exist in five states (S 0 to S 4 ) postcharge accumulation based on Mn(III)/Mn(IV). The system progresses from the most reduced state, S 0 , to the most oxidized state, S 4 , as photons are captured by photosystem II. , The unstable S 4 state reacts with water to produce O 2 .…”