Self‐Assembly of Hybrid Oxidant POM@Cu‐BTC for Enhanced Efficiency and Long‐Term Stability of Perovskite Solar Cells

Abstract The controllable oxidation of spiro‐OMeTAD and improving the stability of hole‐transport materials (HTMs) layer are crucial for good performance and stability of perovskite solar cells (PSCs). Herein, we report an efficient hybrid polyoxometalate@metal–organic framework (POM@MOF) material, [Cu 2 (BTC) 4/3 (H 2 O) 2 ] 6 [H 3 PMo 12 O 40 ] 2 or POM@Cu‐BTC, for the oxidation of spiro‐OMeTAD with Li‐TFSI and TBP. When POM@Cu‐BTC is introduced to the HTM layer as a dopant, the PSCs achieve a superior fill factor of 0.80 and enhanced power conversion efficiency 21.44 %, as well as improved long‐term stability in an ambient atmosphere without encapsulation. The enhanced performance is attributed to the oxidation activity of POM anions and solid‐state nanoparticles. Therefore, this research presents a facile way by using hybrid porous materials to accelerate oxidation of spiro‐OMeTAD, further improving the efficiency and stability of PSCs.