High-Performance Electron-Transport-Layer-Free Quantum Junction Solar Cells with Improved Efficiency Exceeding 10%

Abstract

Colloidal quantum dot solar cells (CQDSCs) are good candidates for low-cost power generators, due to their wide light-response range, high theoretical efficiency, and solution processability. Nevertheless, the generally used metal oxide electron transport layer (MOETL) induced various problems, blocking the performance enhancement of CQDSCs, such as band alignment mismatch, high-energy photon loss, and photoinduced interfacial degradation. In the work described herein, we constructed high-efficiency and air-stable MOETL-free solar cells based on quantum junction device structure, through manipulating the semiconductor and surface-trap properties of PbS CQDs by ligand engineering. A record power conversion efficiency of 10.5% was successfully achieved in our MOETL-free quantum junction solar cells (QJSCs). Increased photogenerated current density was obtained in MOETL-free QJSCs because of the ultraviolet and near-infrared photoresponse enhancement. These unencapsulated MOETL-free QJSCs show long-term air-storage stability (>4000 h). Our work successfully demonstrates the MOETL-free quantum junction as a high-efficiency and stable structure for solar cells, paving a way for application of CQDSCs in the full-spectrum, scalable-production, portable, and flexible photovoltaic technology.

Interfacial Transport Study of Ultra-Thin InN-Enhanced Quantum Dot Solar Cells

“…With the photovoltaic effect of this PN junction, Bell Laboratories prepared solar cells with 4.5% photovoltaic conversion efficiency, which was later increased to 6% [9]. In the following decades, the performance of solar cells has been continuously improved and the types of solar cells have been enriched [10]. Among them, silicon-based solar cells have the longest history of development and have achieved excellent results both in terms of high-efficiency devices and commercialized modules [11].…”

Current Status and Challenges of Solar Cells Based on Semiconductor Nanocrystals

“…Copyright 2018, Tsinghua University Press and Springer-Verlag GmbH Germany. Data in B, C, and D (top) are respectively reproduced from refs , , and. Copyright 2016, 2010, and 2021 American Chemical Society.…”

“…Results in Figure D (top panel) confirm that, without the HTL (0 nm ethanedithiol-coated PbS QDs), the device showed a low J sc , a minimum V oc , and a poor FF. In comparison, all of these parameters were continuously improved by applying different thicknesses of the HTL layer …”

“…In comparison, all of these parameters were continuously improved by applying different thicknesses of the HTL layer. 109…”

A Review on the Effects of ZnO Nanowire Morphology on the Performance of Interpenetrating Bulk Heterojunction Quantum Dot Solar Cells

“…Due to their remarkable multiple exciton generation [ 5 , 6 ], hot carrier effect [ 7 ], possible intermediate band cell structure [ 8 , 9 , 10 ], and multi-junction cell structure [ 11 , 12 ], QDSCs offer the real possibility of boosting energy conversion efficiency beyond the Schockley and Queisser (SQ) limit of 32% for traditional silicon-based SCs [ 13 ]. In the past few decades, QDs have been widely researched and integrated in various kinds of SCs, such as Schottky junction colloidal quantum dot (CQD) SCs [ 14 , 15 ], depleted heterojunction CQDSCs [ 16 , 17 , 18 ], quantum junction CQDSCs [ 19 , 20 , 21 ], and quantum dot-sensitized solar cells (QDSSCs) [ 22 , 23 , 24 ]. However, the PbS QDSCs that have been widely studied have only reached a record efficiency of 13.3% [ 25 ], which is far from the theoretical efficiency of 45% for a single-junction solar cell [ 26 ].…”