Quantum Dot Bridges Enabling Highly Efficient Carbon‐Based Hole Transport Material‐Free Perovskite Solar Cells

Abstract

Realization of improved charge transport with suppressed recombination at the interface of perovskite and carbon electrode is the main key for remarkably increasing the power conversion efficiency of carbon‐based hole transport material (HTM)‐free perovskite solar cells (PSCs). Here, we demonstrate a strategy that builds a perovskite quantum dot (PQD) interlayer, for the first time, to bridge the perovskite absorber and carbon electrode for solving the interface issue in HTM‐free PSCs. It is found that the introduced PQD interlayer concurrently functions as a morphology changer, a defect passivator and a photogenerated hole extractor. Compared with the pristine perovskite film, the PQD‐modified perovskite absorber shows increased contact area and high compatibility with carbon electrode, prolonged carrier lifetime, deduced defect density as well as suppressed recombination. These positive effects, combined with a heterostructure created by perovskite bulks and PQDs facilitating hole transport at the interface, enable an improvement in device efficiency from 16.71% to 17.93%.This article is protected by copyright. All rights reserved.

Sustainable Planar Hole-Transporting Material-Free Carbon Electrode-Based Perovskite Solar Cells: Stability Beyond Two Years

“…These results confirm that the carbon films can serve dual functions as both HTL and electrodes. The efficiency of HTM-free C-PSCs is slightly lower (around 20%) than that of Spiro-OMeTAD C-PSCs due to the dominant charge transfer mechanism within a working device. , As shown in Figure d, the integrated photocurrent densities obtained ( J int ) from the EQE spectra of HTM-free and Spiro-OMeTAD C-PSC devices closely matched those from the J – V curves. These J int values were well-aligned with the J sc values obtained through J – V measurements under AM 1.5G conditions.…”

SnS Quantum Dots Enhancing Carbon-Based Hole Transport Layer-Free Visible Photodetectors

“…In the past two decades, reports on quantum dot interface passivators have emerged in various fields [ 23 , 24 ]. In recent years, Yang et al [ 25 ] investigated the interfacial challenges in carbon-based HTL-free perovskite photodetectors by implementing a perovskite quantum dot interlayer to bridge the perovskite active layer and the carbon electrode. The incorporation of perovskite QDs into the perovskite film led to an increased contact area between the film and the carbon electrode, enhanced carrier lifetime, diminished defect density, and inhibited non-radiative recombination.…”