Interface Engineering and Modulation of Nickel Oxide for High Air‐Stable p‐Type Crystalline Silicon Solar Cells

Abstract Dopant‐free passivating contact crystalline silicon solar cells hold the potential of higher efficiency and cost down. In the hole‐transport terminal, one still faces the challenge of trade‐off between efficiency and stability. In this work, a H‐Al 2 O 3 /NiO x /Ni stacked hole‐transport layer is proposed, where the H‐Al 2 O 3 standing for H‐rich Al 2 O 3 film can effectively reduce the interfacial defects and the high work function Ni metal results in a low contact resistance of 47.12 mΩ cm 2 . Consequently, the solar cell achieves an efficiency of 20.51%, with a fill factor of 84.83%, demonstrating satisfactory stability. This work provides a strategy for reducing interfacial defects and highlights the potential of stacked structure design for enhancing passivated contact solar cell performance.