This Triple-Layer Sunlight Catalyst Supercharges Green Hydrogen by 800%

The new material has eight times better performance than pure cubic silicon carbide

Nowhere is it stated how efficient either material is, other than to say that the researchers are 5-10 years away from a material that's 10% efficient. So they must have an efficiency of less than that I guess.

From the paper, the closest I can see is:

The applied bias photon-to-current efficiency (ABPE) of the Ni(OH)2/Co3O4/3C-SiC photoanode reached 0.47% at 0.65 V vs RHE, which is 15.6 and 1.8 times higher than that of the 3C-SiC and Co3O4/3C-SiC photoanodes, respectively (Figure 4b)

I don't know how representative that measurement is though.