江部日南子助教 (山形大学理学部) と千葉貴之助教のエネルギー移動を利用したペロブスカイトナノ結晶LEDに関する論文がACS Applied Materials Interfaces (9.229) に掲載されました。本成果は、トロント大学Sargent研究室との国際共同研究であり、JSPS DC1、JSPS 科研費、NEDO若手研究者支援事業、JST COIプログラムの支援を受けて行われました。
Energy Transfer between Size-Controlled CsPbI3 Quantum Dots for Light-Emitting Diode Application
Hinako Ebe, Ya-Kun Wang, Narumi Shinotsuka, Yu-Hong Cheng, Mizuho Uwano, Rikuo Suzuki, Yitong Dong, Dongxin Ma, Seungjin Lee, Takayuki Chiba*, Edward H. Sargent, and Junji Kido*
https://pubs.acs.org/doi/full/10.1021/acsami.2c03971
Perovskite quantum dots (PQDs) are applicable in light-emitting diodes (LEDs) owing to their color tunability, high color purity, and excellent photoluminescence quantum yield (PLQY) in the solution state. However, the PQD film obtained through non-radiative recombination by concentration quenching and the formation of surface defects exhibited low PLQY. In this study, we focused on the energy transfer between PQDs with different energy gaps (Eg) to reduce non-radiative recombination in the film state and consequently achieve high device performance. We prepared size-controlled PQDs measuring 10.7 nm (large-size QD; LQD) and 7.9 nm (small-size QD; SQD) with different Eg and observed spectral overlap between SQD emission and LQD absorption. To investigate the FRET from SQD to LQD, we prepared SQD-LQD mixed QD (MQD). The MQD film enhanced LQD emission and exhibited a higher PLQY (52%) with a longer PL decay time (7.4 ns) than those exhibited by the neat LQD film (38% and 6.2 ns). This energy transfer was determined to FRET by photoluminescence excitation and PL decay times. Moreover, the external quantum efficiency of the MQD-based LED increased to 15%, indicating that the FRET process can enhance the PLQY of film and LED efficiency.
城戸・笹部・千葉研究室Webサイト: https://oled.yz.yamagata-u.ac.jp/view.cgi?p=404
https://pubs.acs.org/doi/full/10.1021/acsami.2c03971
Perovskite quantum dots (PQDs) are applicable in light-emitting diodes (LEDs) owing to their color tunability, high color purity, and excellent photoluminescence quantum yield (PLQY) in the solution state. However, the PQD film obtained through non-radiative recombination by concentration quenching and the formation of surface defects exhibited low PLQY. In this study, we focused on the energy transfer between PQDs with different energy gaps (Eg) to reduce non-radiative recombination in the film state and consequently achieve high device performance. We prepared size-controlled PQDs measuring 10.7 nm (large-size QD; LQD) and 7.9 nm (small-size QD; SQD) with different Eg and observed spectral overlap between SQD emission and LQD absorption. To investigate the FRET from SQD to LQD, we prepared SQD-LQD mixed QD (MQD). The MQD film enhanced LQD emission and exhibited a higher PLQY (52%) with a longer PL decay time (7.4 ns) than those exhibited by the neat LQD film (38% and 6.2 ns). This energy transfer was determined to FRET by photoluminescence excitation and PL decay times. Moreover, the external quantum efficiency of the MQD-based LED increased to 15%, indicating that the FRET process can enhance the PLQY of film and LED efficiency.
城戸・笹部・千葉研究室Webサイト: https://oled.yz.yamagata-u.ac.jp/view.cgi?p=404
