A Bi7.38Cr0.62O12+x crystal as a novel visible-light-active photocatalyst up to ∼650 nm

A new type of Bi-based p-type semiconductor, Bi_7.38Cr_0.62O_12+x, has a strong photoelectric response until 647.4 nm and an excellent photocatalytic activity for decomposition and O₂ production.