Xu Jing-Yin, Tong Xin, Besteiro Lucas V, Li Xin, Hu Chenxia, Liu Ruitong, Channa Ali Imran, Zhao Haiguang, Rosei Federico, Govorov Alexander O, Wang Qiang, Wang Zhiming M
Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 610054, P. R. China.
Yangtze Delta Region Institute (Huzhou), University of Electronic Science and Technology of China, Huzhou 313001, P. R. China.
Nanoscale. 2021 Sep 23;13(36):15301-15310. doi: 10.1039/d1nr04199a.
"Giant" core/shell quantum dots (g-QDs) are promising candidates for emerging optoelectronic technologies thanks to their facile structure/composition-tunable optoelectronic properties and outstanding photo-physical/chemical stability. Here, we synthesized a new type of CuInTeSe (CITS)/CdS g-QDs and regulated their optoelectronic properties by controlling the shell thickness. Through increasing the shell thickness, as-prepared g-QDs exhibited tunable red-shifted emission (from 900 to 1200 nm) and prolonged photoluminescence (PL) lifetimes (up to ∼14.0 μs), indicating a formed band structure showing efficient charge separation and transfer, which is further testified by theoretical calculations and ultrafast time-resolved transient absorption (TA) spectroscopy. These CITS/CdS g-QDs with various shell thicknesses can be employed to fabricate photoelectrochemical (PEC) cells, exhibiting improved photoresponse and stability as compared to the bare CITS QD-based devices. The results indicate that the rational design and engineering of g-QDs is very promising for future QD-based optoelectronic technologies.
“巨型”核壳量子点（g-QDs）因其结构/组成易于调节的光电特性以及出色的光物理/化学稳定性，成为新兴光电子技术的有前途的候选材料。在此，我们合成了一种新型的CuInTeSe（CITS）/CdS g-QDs，并通过控制壳层厚度来调节其光电特性。通过增加壳层厚度，所制备的g-QDs表现出可调的红移发射（从900到1200 nm）和延长的光致发光（PL）寿命（高达约14.0 μs），这表明形成了能实现有效电荷分离和转移的能带结构，理论计算和超快时间分辨瞬态吸收（TA）光谱进一步证实了这一点。这些具有不同壳层厚度的CITS/CdS g-QDs可用于制造光电化学（PEC）电池，与基于裸CITS量子点的器件相比，表现出改善的光响应和稳定性。结果表明，对g-QDs进行合理设计和工程化对于未来基于量子点的光电子技术非常有前景。
