Cuprous oxide single-crystal film assisted highly efficient solar hydrogen production on large ships for long-term energy storage and zero-emission power generation

Designing and manufacturing green ships and achieving zero emissions is one of the important trends in modern society for energy conservation and emission reduction. This article explores a novel combined technology of photovoltaic and photoelectrocatalysis to achieve efficient solar hydrogen production, in which the onset voltage for solar water splitting moved from 1.23 V forward to 0.59 V under the assistance of p-Cu₂O single-crystal film. After implementing on a 110-m barge for the first time, a solar to hydrogen conversion efficiency of 9.79% has been achieved, which is state-of-the-art in large practical projects, producing 63 Nm³ of hydrogen every day accompanied with an outstanding Faraday efficiency higher than 98.2%. The hydrogen has been purified and compressed for storage, then generates 96 kWh of electricity on demand through the fuel cell stack (43% efficiency). The hydrogen-powered ship can reduce 6.1 tons of diesel consumption and 18.9 tons of carbon dioxide emissions each year.