SQUID magnetometry combined with in situ cyclic voltammetry: A case study of tunable magnetism of γ-Fe2O3 nanoparticles

► SQUID magnetometry is combined with in situ cyclic voltammetry. ► A three-electrode chemical cell is designed for operation in a SQUID magnetometer. ► Variations of magnetism can be directly related to electrochemical processes. ► Reversible variations of the magnetic moment of maghemite nanoparticles up to 4.2%. ► For nanocrystalline maghemite charging effects strongly depend on voltage regime.