Thanks. Tantalizingly, some plain efficiency measurements seem to be contained in articles supplementary material.

> "Online O2 detection also confirmed quantitative OER Faradaic efficiency with and without the presence of a magnetic field (Supplementary Fig. 17)."

But it looks to me like this effect is demonstrated as really significant already, for all the catalysts bar one. Application of it cant be far away. A bit like sticking a magnet on an engine block and getting loads more horsepower !