Fig. 5
Proton-assisted control of oxygen vacancy formation during cyclic voltammetry. Cyclic voltammograms at scan rates: a 50 mV s-1. b 300 mV s-1. c 1000 mV s-1. d 3000 mV s-1. e–h Corresponding XPS Ce 3d spectra. i–l Corresponding XPS O 1s spectra
