Highly Emissive Blue Quantum Dots with Superior Thermal Stability via In Situ Surface Reconstruction of Mixed CsPbBr3–Cs4PbBr6 Nanocrystals
Abstract Although metal halide perovskites are candidate high‐performance light‐emitting diode (LED) materials, blue perovskite LEDs are problematic: mixed‐halide materials are susceptible to phase segregation and bromide‐based perovskite quantum dots (QDs) have low stability. Herein, a novel strate...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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Wiley
2022-02-01
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| Series: | Advanced Science |
| Subjects: | |
| Online Access: | https://doi.org/10.1002/advs.202104660 |
| _version_ | 1818330464013778944 |
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| author | Hyeonjung Kim Jong Hyun Park Kangyong Kim Dongryeol Lee Myoung Hoon Song Jongnam Park |
| author_facet | Hyeonjung Kim Jong Hyun Park Kangyong Kim Dongryeol Lee Myoung Hoon Song Jongnam Park |
| author_sort | Hyeonjung Kim |
| collection | DOAJ |
| description | Abstract Although metal halide perovskites are candidate high‐performance light‐emitting diode (LED) materials, blue perovskite LEDs are problematic: mixed‐halide materials are susceptible to phase segregation and bromide‐based perovskite quantum dots (QDs) have low stability. Herein, a novel strategy for highly efficient, stable cesium lead bromide (CsPbBr3) QDs via in situ surface reconstruction of CsPbBr3–Cs4PbBr6 nanocrystals (NCs) is reported. By controlling precursor reactivity, the ratio of CsPbBr3 to Cs4PbBr6 NCs is successfully modulated. A high photoluminescence quantum yield (PLQY) of >90% at 470 nm is obtained because octahedron CsPbBr3 QD surface defects are removed by the Cs4PbBr6 NCs. The defect‐engineered QDs exhibit high colloidal stability, retaining >90% of their initial PLQY after >120 days of ambient storage. Furthermore, thermal stability is demonstrated by a lack of heat‐induced aggregation at 120 °C. Blue LEDs fabricated from CsPbBr3 QDs with reconstructed surfaces exhibit a maximum external quantum efficiency of 4.65% at 480 nm and excellent spectral stability. |
| first_indexed | 2024-12-13T13:04:22Z |
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| id | doaj.art-55d60b8034b04d91b95398d7c907a6b3 |
| institution | Directory Open Access Journal |
| issn | 2198-3844 |
| language | English |
| last_indexed | 2024-12-13T13:04:22Z |
| publishDate | 2022-02-01 |
| publisher | Wiley |
| record_format | Article |
| series | Advanced Science |
| spelling | doaj.art-55d60b8034b04d91b95398d7c907a6b32022-12-21T23:44:53ZengWileyAdvanced Science2198-38442022-02-0195n/an/a10.1002/advs.202104660Highly Emissive Blue Quantum Dots with Superior Thermal Stability via In Situ Surface Reconstruction of Mixed CsPbBr3–Cs4PbBr6 NanocrystalsHyeonjung Kim0Jong Hyun Park1Kangyong Kim2Dongryeol Lee3Myoung Hoon Song4Jongnam Park5School of Energy and Chemical Engineering Ulsan National Institute of Science and Technology (UNIST) UNIST‐gil 50 Ulsan 44919 Republic of KoreaDepartment of Materials Science and Engineering Ulsan National Institute of Science and Technology (UNIST) UNIST‐gil 50 Ulsan 44919 Republic of KoreaSchool of Energy and Chemical Engineering Ulsan National Institute of Science and Technology (UNIST) UNIST‐gil 50 Ulsan 44919 Republic of KoreaDepartment of Materials Science and Engineering Ulsan National Institute of Science and Technology (UNIST) UNIST‐gil 50 Ulsan 44919 Republic of KoreaDepartment of Materials Science and Engineering Ulsan National Institute of Science and Technology (UNIST) UNIST‐gil 50 Ulsan 44919 Republic of KoreaSchool of Energy and Chemical Engineering Ulsan National Institute of Science and Technology (UNIST) UNIST‐gil 50 Ulsan 44919 Republic of KoreaAbstract Although metal halide perovskites are candidate high‐performance light‐emitting diode (LED) materials, blue perovskite LEDs are problematic: mixed‐halide materials are susceptible to phase segregation and bromide‐based perovskite quantum dots (QDs) have low stability. Herein, a novel strategy for highly efficient, stable cesium lead bromide (CsPbBr3) QDs via in situ surface reconstruction of CsPbBr3–Cs4PbBr6 nanocrystals (NCs) is reported. By controlling precursor reactivity, the ratio of CsPbBr3 to Cs4PbBr6 NCs is successfully modulated. A high photoluminescence quantum yield (PLQY) of >90% at 470 nm is obtained because octahedron CsPbBr3 QD surface defects are removed by the Cs4PbBr6 NCs. The defect‐engineered QDs exhibit high colloidal stability, retaining >90% of their initial PLQY after >120 days of ambient storage. Furthermore, thermal stability is demonstrated by a lack of heat‐induced aggregation at 120 °C. Blue LEDs fabricated from CsPbBr3 QDs with reconstructed surfaces exhibit a maximum external quantum efficiency of 4.65% at 480 nm and excellent spectral stability.https://doi.org/10.1002/advs.202104660blue quantum dotslight‐emitting diodesperovskitessurface reconstructionthermal stability |
| spellingShingle | Hyeonjung Kim Jong Hyun Park Kangyong Kim Dongryeol Lee Myoung Hoon Song Jongnam Park Highly Emissive Blue Quantum Dots with Superior Thermal Stability via In Situ Surface Reconstruction of Mixed CsPbBr3–Cs4PbBr6 Nanocrystals Advanced Science blue quantum dots light‐emitting diodes perovskites surface reconstruction thermal stability |
| title | Highly Emissive Blue Quantum Dots with Superior Thermal Stability via In Situ Surface Reconstruction of Mixed CsPbBr3–Cs4PbBr6 Nanocrystals |
| title_full | Highly Emissive Blue Quantum Dots with Superior Thermal Stability via In Situ Surface Reconstruction of Mixed CsPbBr3–Cs4PbBr6 Nanocrystals |
| title_fullStr | Highly Emissive Blue Quantum Dots with Superior Thermal Stability via In Situ Surface Reconstruction of Mixed CsPbBr3–Cs4PbBr6 Nanocrystals |
| title_full_unstemmed | Highly Emissive Blue Quantum Dots with Superior Thermal Stability via In Situ Surface Reconstruction of Mixed CsPbBr3–Cs4PbBr6 Nanocrystals |
| title_short | Highly Emissive Blue Quantum Dots with Superior Thermal Stability via In Situ Surface Reconstruction of Mixed CsPbBr3–Cs4PbBr6 Nanocrystals |
| title_sort | highly emissive blue quantum dots with superior thermal stability via in situ surface reconstruction of mixed cspbbr3 cs4pbbr6 nanocrystals |
| topic | blue quantum dots light‐emitting diodes perovskites surface reconstruction thermal stability |
| url | https://doi.org/10.1002/advs.202104660 |
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