Organic p-type materials are potential candidates as solution processable hole transport materials (HTMs) for colloidal quantum dot solar cells (CQDSCs) because of their good hole accepting/electron blocking characteristics and synthetic versatility. However, organic HTMs have still demonstrated inferior performance compared to conventional p-type CQD HTMs. In this work, organic π-conjugated polymer (π-CP) based HTMs, which can achieve performance superior to that of state-of-the-art HTM, p-type CQDs, are developed. The molecular engineering of the π-CPs alters their optoelectronic properties, and the charge generation and collection in CQDSCs using them are substantially improved. A device using PBDTTPD-HT achieves power conversion efficiency (PCE) of 11.53% with decent air-storage stability. This is the highest reported PCE among CQDSCs using organic HTMs, and even higher than the reported best solid-state ligand exchange-free CQDSC using pCQD-HTM. From the viewpoint of device processing, device fabrication does not require any solid-state ligand exchange step or layer-by-layer deposition process, which is favorable for exploiting commercial processing techniques.
Bibliographical noteFunding Information:
M.A.M. and H.A. contributed equally to this work. The authors gratefully acknowledge support from the New and Renewable Energy Core Technology Program of the Korea Institute of Energy Technology Evaluation and Planning (KETEP), granted financial resources from the Ministry of Trade, Industry and Energy, Republic of Korea (No. 20163030013960), and the National Research Foundation (NRF) Grant funded by the Korean Government (MSIP, Grant Nos. 2016R1A5A1012966 and 2019R1A2C2087218). This work was also supported by the New Faculty Research Fund (1.190108.01) of UNIST (Ulsan National Institute of Science & Technology).
All Science Journal Classification (ASJC) codes
- Renewable Energy, Sustainability and the Environment
- Materials Science(all)