Rational implementation of auxiliary voltage in heterojunction structures to improve charge separation efficiency is an effective method to enhance photoelectrode performances. This work reported a novel p-n type heterojunction structure photoelectrode, constructed with nitrogen-doped bis-rare-earth metal–organic frameworks (NH2-La/Ce MOFs) and titanium dioxide nanoflowers (NTFs) on porous titanium foams (Ds-NH2-La/Ce MOFs/NTFs/Ti).The application in treating water pollution demonstrated that the Photoelectrocatalytic degradation of ibuprofen (IBP) at an auxiliary bias voltage of 1.5 V for 120 min reached 98.3 %. The density Functional Theory (DFT) calculations revealed that nitrogen-doped bis-rare-earth MOFs effectively reduce the bandgap and establish an internal electric field, which facilitated carrier separation and transport. The double-coupled n-n heterojunction structure designed herein share a good tactic to develop MOFs-based new photoelectrodes for future.