Defective MWCNT Enabled Dual Interface Coupling for Carbon-Based Perovskite Solar Cells with Efficiency Exceeding 22

摘要

Suffering from sluggish charge transfer kinetics, carbon-based perovskitesolar cells (C-PSCs) lag far behind the Ag/Au-based normal PSCs in powerconversion efficiency (PCE). Herein, the use of defective multi-walled CNT(D-MWCNT) is demonstrated to tune the charge transfer kinetics regardinghole transport layer (HTL) and the interface between HTL and carbon electrode.Benefiting from the electrostatic dipole moment interaction between theterminal oxygen-containing groups of D-MWCNT and 2,2′,7,7′-tetrakis(N,Ndi-p-methoxyphenylamine)-9,9′-spirobifluorene, an interface coupling atmolecular level is established and in turn, allows rapid charge transfer byedge effect induced electron redistribution and 1D hyper-channels. Meanwhile,a seamless connection between HTL and carbon electrode is achievedin a novel modular C-PSCs due to D-MWCNT induced interface coupling withgraphene at nanometer scale. Based on this strategy, high PCEs up to 22.07(with a certified record PCE of 21.9 to date for C-PSCs) and excellent operationalstability have been achieved.