ひかり触媒しょくばい作用さようじゃありませんでした
hikarishokuba isayōja arimasendeshita

Noun
Desu Copula

The polite, past negative form of 光触媒作用

1. It wasn't photocatalytic action.; It wasn't a photocatalytic effect.

Past/Perfective
Negative
Polite
Terminal Form