About this Abstract |
Meeting |
2021 TMS Annual Meeting & Exhibition
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Symposium
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Functional Nanomaterials: Functional Low-dimensional Materials (0D, 1D, 2D) Driving Innovations in Electronics, Energy, Sensors, and Environmental Engineering and Science 2021
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Presentation Title |
Direct Backbone Attachment of Polyesters on Grain Boundaries Enhances Chemical Stability and Suppressing Ion Migration in CH3NH3PbI3 Hybrid Perovskite Solar Cells |
Author(s) |
Chang-Yong Nam |
On-Site Speaker (Planned) |
Chang-Yong Nam |
Abstract Scope |
Here, we have identified a new polar polymer, polycaprolactone (PCL), to passivate grain boundaries (GBs) of methylammonium lead triiodide (MAPbI3) perovskites with only 1 – 2 polymer monolayers via direct backbone attachment. The solar cell with passivated MAPbI3 exhibited improved power conversion efficiencies up to 20.1 %, with 90 % of the initial PCE being preserved after 400-h ambient storage, and 80 % even after 100-h, 85 C aging. The improved stability indicates critical roles of PCL GB passivation in retarding moisture-induced decomposition and suppressing ion migration within perovskites. Time-of-flight secondary ion mass spectrometry revealed that I- ions could actively migrate into electrode, hole transport layer, and their interface in non-passivated device, even without externally applied electric field, while such migrations were significantly mitigated in PCL-passivated devices. This effective GB passivation by PCL suggests an important potential of polymer additives towards the development of stable high-performance perovskite solar cells. |
Proceedings Inclusion? |
Planned: |