Polymer Acceptor Based on BN Units with Enhanced Electron Mobility for Efficient All-Polymer Solar Cells

We demonstrate that polymer electron acceptors with excellent all-polymer solar-cell (all-PSC) device performance can be developed from polymer electron donors by using BN units. By alleviating the steric hindrance effect of the bulky pendant moieties on the conjugated polymers that contain BN units, the - stacking distance of polymer backbones is decreased and the electron mobility is consequently enhanced by nearly two orders of magnitude. As a result, the power conversion efficiency of all-PSCs with the polymer acting as the electron acceptor is greatly improved from 0.12% to 5.04%. This PCE value is comparable to that of the best all-PSCs with state-of-the-art polymer acceptors.