Photocatalytic activity of Er3+, Yb3+ doped Bi5O7I

► Er3+, Yb3+ as upconversion(UC) agents were doped into the Bi5O7I photocatalyst. ► The Er3+, Yb3+ doped Bi5O7I has better activity than the undoped sample. ► The UC agent doping into the photocatalyst is a feasible strategy in photocatalysis.