The performance of perovskite solar cells is predominantly limited by non-radiative recombination, either through trap-assisted recombination in the absorber layer or via minority carrier recombination at the perovskite/transport layer interfaces. Here, we use transient and absolute photoluminescence imaging to visualize all non-radiative recombination pathways in planar pin-type perovskite solar cells with undoped organic charge transport layers. We find significant quasi-Fermi-level splitting losses (135 meV) in the perovskite bulk, whereas interfacial recombination results in an additional free energy loss of 80 meV at each individual interface, which limits the open-circuit voltage (V_OC) of the complete cell to ~1.12 V. Inserting ultrathin interlayers between the perovskite and transport layers leads to a substantial reduction of these interfacial losses at both the p and n contacts. Using this knowledge and approach, we demonstrate reproducible dopant-free 1 cm² perovskite solar cells surpassing 20% efficiency (19.83% certified) with stabilized power output, a high V_OC (1.17 V) and record fill factor (>81%).

钙钛矿太阳能电池的性能主要受到非辐射复合的限制，要么通过吸收层中的陷阱辅助复合，要么通过钙钛矿/传输层界面处的少数载流子复合。这里，我们使用瞬态和绝对光致发光成像来可视化在平面销所有的非辐射复合通道-型钙钛矿太阳能电池与未掺杂的有机电荷传输层。我们发现钙钛矿块中存在明显的准费米能级分裂损耗（135 meV），而界面复合会在每个单独的界面处造成80 meV的额外自由能损耗，从而限制了开路电压（V _OC），将整个电池的电导率降低到〜1.12V。在钙钛矿和传输层之间插入超薄中间层可显着降低p和n接触处的这些界面损耗。使用这种知识和方法，我们证明重现的自由掺杂剂1厘米^2个钙钛矿型太阳能电池超过20％的效率（19.83％认证）与稳定的功率输出，高V _OC（1.17 V）和记录填充因子（> 81％）。