Hydroiodic Acid Additive Enhanced the Performance and Stability of PbS-QDs Solar Cells via Suppressing Hydroxyl Ligand

• Published in: Nano-micro letters Vol. 12; no. 1; pp. 37 - 12
• Main Authors: Yang, Xiaokun, Yang, Ji, Khan, Jahangeer, Deng, Hui, Yuan, Shengjie, Zhang, Jian, Xia, Yong, Deng, Feng, Zhou, Xue, Umar, Farooq, Jin, Zhixin, Song, Haisheng, Cheng, Chun, Sabry, Mohamed, Tang, Jiang
• Format: Journal Article
• Language: English
• Published: Singapore Springer Singapore 24.01.2020; Springer Nature B.V; SpringerOpen
• Subjects: Carrier mobility; Control equipment; Energy conversion efficiency; Engineering; HI additive; Hydroxyl ligand; Iodine; Ligands; Nanoscale Science and Technology; Nanotechnology; Nanotechnology and Microengineering; Optoelectronic devices; Performance enhancement; Photovoltaic cells; Quantum dots; Quantum dots ink; Solar cells; Strategy; Surface passivation; Solar cells; Quantum dots ink; HI additive; Surface passivation; Hydroxyl ligand
• ISSN: 2311-6706; 2150-5551; 2150-5551
• DOI: 10.1007/s40820-020-0372-z

Highlights The hydroiodic acid was explored systematically to modify PbS quantum dots (QDs) ink process, which could remove trap states by hydroxyl ligand and improve iodine passivation on the PbS-QDs surface. This strategy solved the essential question of PbS-QDs ink process and showed the favorable application prospects in QDs technology. The recent emerging progress of quantum dot ink (QD-ink) has overcome the complexity of multiple-step colloidal QD (CQD) film preparation and pronouncedly promoted the device performance. However, the detrimental hydroxyl (OH) ligands induced from synthesis procedure have not been completely removed. Here, a halide ligand additive strategy was devised to optimize QD-ink process. It simultaneously reduced sub-bandgap states and converted them into iodide-passivated surface, which increase carrier mobility of the QDs films and achieve thicker absorber with improved performances. The corresponding power conversion efficiency of this optimized device reached 10.78%. (The control device was 9.56%.) Therefore, this stratege can support as a candidate strategy to solve the QD original limitation caused by hydroxyl ligands, which is also compatible with other CQD-based optoelectronic devices.