Stable CsPb1-xZnxI3 Colloidal Quantum Dots with Ultralow Density of Trap States for High-Performance Solar Cells
Author(s): Bi, CH (Bi, Chenghao); Sun, XJ (Sun, Xuejiao); Huang, X (Huang, Xin); Wang, SX (Wang, Shixun); Yuan, JF (Yuan, Jifeng); Wang, JX (Wang, Jun Xi); Pullerits, T (Pullerits, Tonu); Tian, JJ (Tian, Jianjun)
Source: CHEMISTRY OF MATERIALS Volume: 32 Issue: 14 Pages: 6105-6113 DOI: 10.1021/acs.chemmater.0c01750 Published: JUL 28 2020
Abstract: All inorganic halide perovskites in the form of colloidal quantum dots (QDs) have come into people's view as one of the potential materials for the high-efficiency solar cells; nevertheless, the high surface trap density and poor stability of QDs restrict the performance improvement and application. Here, we obtain colloidal inorganic perovskite CsPb1-xZnxI3 QDs by the hot-injection synthesis process with the addition of ZnCl2. Synchrotron-based X-ray absorption fine structures demonstrate that the guest Zn2+ ions are doped into the CsPbI3 structure to improve the local ordering of the lattice of the perovskite, reducing the octahedral distortions. The increase of the Goldschmidt tolerance factor and the Pb-I bond energy also enhance the stability of the perovskite structure. Furthermore, the Cl- ions from ZnCl2 occupy the iodide vacancies of the perovskite to decrease the nonradiative recombination. The synergistic effect of doping and defect passivation makes for stable colloidal CsPb0.97Zn0.03I3 QDs with ultralow density of trap states. The champion solar cell based on the QDs shows a power conversion efficiency of 14.8% and a largely improved stability under ambient conditions.
Accession Number: WOS:000557753300019
Author Identifiers:
Author Web of Science ResearcherID ORCID Number
Pullerits, Tonu A-5603-2010 0000-0003-1428-5564
ISSN: 0897-4756
eISSN: 1520-5002
Full Text: https://pubs.acs.org/doi/10.1021/acs.chemmater.0c01750