Gong Maogang, Alamri Mohammed, Ewing Dan, Sadeghi Seyed M, Wu Judy Z
Department of Physics and Astronomy, University of Kansas, Lawrence, KS, 66045, USA.
Department of Energy's National Security Campus, Kansas City, MO, 64147, USA.
Adv Mater. 2020 Jul;32(26):e2002163. doi: 10.1002/adma.202002163. Epub 2020 May 25.
Localized surface plasmon resonance (LSPR) is shown to be effective in trapping light for enhanced light absorption and hence performance in photonic and optoelectronic devices. Implementation of LSPR in all-inorganic perovskite nanocrystals (PNCs) is particularly important considering their unique advantages in optoelectronics. Motivated by this, the first success in colloidal synthesis of AuCu/CsPbCl core/shell PNCs and observation of enhanced light absorption by the perovskite CsPbCl shell of thickness in the range of 2-4 nm, enabled by the LSPR AuCu core of an average diameter of 7.1 nm, is reported. This enhanced light absorption leads to a remarkably enhanced photoresponse in PNCs/graphene nanohybrid photodetectors using the AuCu/CsPbCl core/shell PNCs, by more than 30 times as compared to the counterparts with CsPbCl PNCs only (8-12 nm in dimension). This result illustrates the feasibility in implementation of LSPR light trapping directly in core/shell PNCs for high-performance optoelectronics.
局域表面等离子体共振（LSPR）被证明在捕获光以增强光吸收从而提高光子和光电器件性能方面是有效的。考虑到全无机钙钛矿纳米晶体（PNCs）在光电子学中的独特优势，在其中实现LSPR尤为重要。受此启发，本文报道了在胶体合成AuCu/CsPbCl核壳型PNCs方面取得的首次成功，并观察到由平均直径为7.1 nm的LSPR AuCu核所引发的、厚度在2 - 4 nm范围内的钙钛矿CsPbCl壳层的光吸收增强现象。这种增强的光吸收使得使用AuCu/CsPbCl核壳型PNCs的PNCs/石墨烯纳米混合光电探测器中的光响应显著增强，与仅使用CsPbCl PNCs（尺寸为8 - 12 nm）的同类探测器相比，增强了30倍以上。这一结果说明了直接在核壳型PNCs中实现LSPR光捕获以用于高性能光电子学的可行性。
