An　adaptive　Ni-based　catalyst　derived　from　soluble　nickel-bipyridine　[Ni(bpy)3]2+　exhibits　increased　active　sites,　and　yet　is　nearly　transparent　to　solar　light;　hence,　this　catalyst　on　nickel-sputtered　Si　exhibits　a　250　mV　negative　shift　of　overpotential　at　20　mA　cm−2　relative　to　the　pristine　Ni/Si　photoanode.　©　2025　The　Royal　Society　of　Chemistry.