Phase Stable and Less-Defect Perovskite Quantum Dots: Optical Property, Photoexcited Hot Carrier Dynamics, Charge Transfer and Application to Optoelectronic Devices

Author(s):  
Qing Shen ◽  
Feng Liu ◽  
Chao Ding ◽  
Yaohong Zhang ◽  
Taro Toyoda ◽  
...  
Crystals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 419
Author(s):  
Saradh Prasad ◽  
Mamduh J. Aljaafreh ◽  
Mohamad S. AlSalhi ◽  
Abeer Alshammari

The notable photophysical characteristics of perovskite quantum dots (PQDs) (CsPbBr3) are suitable for optoelectronic devices. However, the performance of PQDs is unstable because of their surface defects. One way to address the instability is to passivate PQDs using different organic (polymers, oligomers, and dendrimers) or inorganic (ZnS, PbS) materials. In this study, we performed steady-state spectroscopic investigations to measure the photoluminescence (PL), absorption (A), transmission (T), and reflectance (R) of perovskite quantum dots (CsPbBr3) and ethylene vinyl acetate/terpene phenol (1%) (EVA-TPR (1%), or EVA) copolymer/perovskite composites in thin films with a thickness of 352 ± 5 nm. EVA is highly transparent because of its large band gap; furthermore, it is inexpensive and easy to process. However, the compatibility between PQDs and EVA should be established; therefore, a series of analyses was performed to compute parameters, such as the band gap, the coefficients of absorbance and extinction, the index of refractivity, and the dielectric constant (real and imaginary parts), from the data obtained from the above investigation. Finally, the optical conductivities of the films were studied. All these analyses showed that the EVA/PQDs were more efficient and stable both physically and optically. Hence, EVA/PQDs could become copolymer/perovskite active materials suitable for optoelectronic devices, such as solar cells and perovskite/polymer light-emitting diodes (PPLEDs).


2021 ◽  
Vol 6 (38) ◽  
pp. 10165-10177
Author(s):  
Virendra Kumar ◽  
Vandana Nagal ◽  
Shubhda Srivastava ◽  
Mahesh Kumar ◽  
Bipin K. Gupta ◽  
...  

2020 ◽  
Vol 6 (7) ◽  
pp. eaay5225 ◽  
Author(s):  
Basudev Pradhan ◽  
Sonali Das ◽  
Jinxin Li ◽  
Farzana Chowdhury ◽  
Jayesh Cherusseri ◽  
...  

Organic-inorganic halide perovskite quantum dots (PQDs) constitute an attractive class of materials for many optoelectronic applications. However, their charge transport properties are inferior to materials like graphene. On the other hand, the charge generation efficiency of graphene is too low to be used in many optoelectronic applications. Here, we demonstrate the development of ultrathin phototransistors and photonic synapses using a graphene-PQD (G-PQD) superstructure prepared by growing PQDs directly from a graphene lattice. We show that the G-PQDs superstructure synchronizes efficient charge generation and transport on a single platform. G-PQD phototransistors exhibit excellent responsivity of 1.4 × 108 AW–1 and specific detectivity of 4.72 × 1015 Jones at 430 nm. Moreover, the light-assisted memory effect of these superstructures enables photonic synaptic behavior, where neuromorphic computing is demonstrated by facial recognition with the assistance of machine learning. We anticipate that the G-PQD superstructures will bolster new directions in the development of highly efficient optoelectronic devices.


2016 ◽  
Author(s):  
Paul D. Cunningham ◽  
Paul A. Lane ◽  
Joseph S. Melinger ◽  
Okan Esenturk ◽  
Edwin J. Heilweil

2005 ◽  
Vol 71 (19) ◽  
Author(s):  
Artem V. Maleev ◽  
Ivan V. Ignatiev ◽  
Il’ya Ya. Gerlovin ◽  
Igor E. Kozin ◽  
Yasuaki Masumoto

Catalysts ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 957
Author(s):  
ChaeHyun Lee ◽  
Soo Jeong Lee ◽  
YeJi Shin ◽  
Yeonsu Woo ◽  
Sung-Hwan Han ◽  
...  

Making high-quality raw materials is the key to open the versatile potential of next generation materials. All-inorganic CsPbX3 (X: Cl−, Br−, and/or I−) perovskite quantum dots (PQDs) have been applied in various optoelectronic devices, such as photocatalysis, hydrogen evolution, solar cells, and light-emitting diodes, due to their outstanding photophysical properties, such as high photoluminescence quantum yield (PLQY), absorption cross-section, efficient charge separation, and so on. Specifically, for further improvement of the PLQY of the PQDs, it is essential to diminish the non-radiative charge recombination processes. In this work, we approached two ways to control the non-radiative charge recombination processes through synthetic and post-synthetic processes. Firstly, we proposed how refinement of the conventional recrystallization process for PbI2 contributes to higher PLQY of the PQDs. Secondly, after halide exchange from CsPbI3 PQDs to CsPbBr3, through an in situ spectroelectrochemical setup, we monitored the positive correlation between bromide deposition of on the surface of the perovskite and photoluminescence improvement of the CsPbBr3 perovskite film through electrodeposition. These two strategies could provide a way to enhance the photophysical properties of the perovskites for application to various perovskite-based optoelectronic devices.


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