Synergistic Energetic Realignment and Interfacial Passivation via Perovskite Nanocrystal-Doped Spiro-OMeTAD for Efficient Planar Perovskite Solar Cells
Year: 2026
Type: preprint
Abstract: Non-radiative recombination at the perovskite/hole transport layer (HTL) interface fundamentally constrains the open-circuit voltage (Voc) and charge-collection efficiency of planar perovskite solar cells. In this work, we report an effective interface engineering strategy of incorporating MAPb (IxBr1-x)3 nanocrystals (NC) into a Spiro-OMeTAD matrix which is used as HTL. Consequently, planar n-i-p devices incorporating the composite HTL deliver an enhanced power conversion efficiency of 20.31 %, highlighted by a surge in 𝑉𝑜𝑐 (up to 1.1 V) alongside stable photocurrent density of 24.62 mA cm −2 . Electrochemical impedance spectroscopy (EIS) reveals that NC incorporation results in reduced bulk resistance of the Spiro-OMeTAD layer. Furthermore, systematic analysis of the characteristic time constant extracted from EIS measurements provides evidence of halide-ion redistribution which modulate the interfacial energetics and enhance the built-in electric field, thereby contributing to the observed improvement in PCE. This work highlights the potential of nanocrystal-engineered HTLs as an effective approach for potential suppression of interfacial recombination and developing defectpassivated, high-voltage perovskite solar cells.
Source: ChemRxiv
Institution: Indian Institute of Science Bangalore
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7204845113