Lithium and Silver Co-Doped Nickel Oxide Hole-Transporting Layer Boosting the Efficiency and Stability of Inverted...

In this work, a lithium and silver co-doping strategy has been successfully implied to prepare NiO _x films for high performance inverted planar perovskite solar cells (PSCs). Compared to the pristine and single-doped NiO _x, the Li and Ag co-doping approach exhibits the synergistic effect and can endow NiO _x films with higher electrical conductivity, higher hole mobility and better interface energy band alignment with perovskite active layers. Moreover, the perovskite film with enhanced crystallinity can be obtained induced by the Li,Ag:NiO _x film. The PSC with Li,Ag:NiO _x HTL shows a high power conversion efficiency (PCE) up to 19.24% and less hysteresis effect, which outperforms the devices with the pristine NiO _x or single-doped NiO _x HTLs. Meanwhile, the Li,Ag:NiO _x device can retain 95% of its initial PCE after storage at the relative humidity of 30 ± 2% in 30 days without encapsulation. Our work demonstrates that lithium and silver co-doping is a promising route for realizing efficient p-type NiO _x HTL, which provides a simple way to boost the efficient and stable of inverted planar PSCs.