Naslov
Spontaneous Formation of Nanocrystals in Amorphous Matrix: Alternative Pathway to Bright Emission in Quasi-2D Perovskites

Autori
Liu, Fangzhou ; Chan, Christopher Chang Sing ; Ma, Chao ; Tam, Ho Won ; Leung, Tik Lun ; Lin, Jingyang ; Djurišić, Aleksandra B. ; Wong, Kam Sing ; Popović, Jasminka ; Ng, Alan Man Ching ; Chan, Wai Kin ; Chen, Wei ; He, Zhubing ; Adesina, Ayotunde Emmanuel ; Foo, Yishu ; Zapien, Juan Antonio

Izvornik
Advanced optical materials (2195-1071) 7 (2019), 19; 1900269, 4

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
Quasi‐2D ; Perovskites

Sažetak
Significant enhancement of the light emission in Ruddlesden–Popper organic–inorganic halide perovskites is obtained by antisolvent induced spontaneous formation of nanocrystals in an amorphous matrix. This morphology change results in the passivation of defects and significant enhancement of light emission and 16 times higher photoluminescence quantum yield (PLQY), and it is applicable to different spacer cations. The use of trioctylphosphine oxide results in further defect passivation leading to an increase in PLQY (≈2.3 times), the suppression of lower energy emission in low temperature photoluminescence spectra, the dominance of radiative recombination, and the disappearance of thermal quenching of the luminescence. The proposed method offers a reproducible, controllable, and antisolvent‐ insensitive alternative to energy landscape engineering to utilize energy funneling phenomenon to achieve bright emission. Instead of facilitating fast energy transfer from lower to higher number of perovskite sheets to prevent nonradiative losses, it is demonstrated that defects can be effectively passivated via morphology control and the use of a passivating agent, so that bright emission can be obtained from single phase nanocrystals embedded in amorphous matrix, resulting in light emitting diodes with a maximum external quantum efficiency of 2.25%.

Izvorni jezik
Engleski

Znanstvena područja
Fizika, Kemija

POVEZANOST RADA