Merged interface construction toward ultra-low Voc loss in inverted two-dimensional Dion–Jacobson perovskite solar cells with efficiency over 18%

By introducing a pretreatment combined with a merged annealing method, a dual-function PC₆₁BM, which passivates interface defects and improves charge transport, was achieved to boost the PCE of 2D Dion–Jacobson perovskite solar cells to over 18%.