The photovoltaic performance of the dye-sensitized solar cell is enhanced remarkably through using magnetic counter electrode. This kind of counter electrode catalyst is a core-shell structured paramagnetic carbon sphere using carbon as shell and paramagnetic Fe3O4 as core. After analyzing the catalytic behaviors of carbon sphere, Fe3O4, and paramagnetic carbon sphere on nonmagnetic and magnetic substrates toward the cobalt complex redox couple, it is proved that the internal magnetic field is conducive to both charge transfer and the mass transport processes in the electrode/electrolyte interfaces. The dye-sensitized solar cell using the magnetic carbon sphere counter electrode on magnetic substrate yields a power conversion efficiency of 10.71%, much higher than those using magnetic carbon sphere counter electrode on conductive glass (8.74%), carbon sphere counter electrode on magnetic substrate (8.50%), and Fe3O4 counter electrode on magnetic substrate (6.86%). (C) 2018 Elsevier Ltd. All rights reserved.