Enhanced transfer efficiency of plasmonic hot-electron across Au/GaN interface by the piezo-phototronic effect. (March 2022)

• Record Type: Journal Article
• Authors: Zhu, Yu; Deng, Congcong; He, Chenguang; Zhao, Wei; Chen, Zhitao; Li, Shuti; Zhang, Kang; Wang, Xingfu
• Is Part Of: Nano energy. Volume 93(2022)
• Publication Date: 2022-03
• Subjects: piezo-phototronic effect -- hot-electron -- transfer dynamic -- GaN -- ultraviolet photodetector; Nanoscience -- Periodicals; Nanotechnology -- Periodicals; Nanostructured materials -- Periodicals; Power resources -- Technological innovations -- Periodicals; Nanoscience; Nanostructured materials; Nanotechnology; Power resources -- Technological innovations; Periodicals; 621.042
• DOI: 10.1016/j.nanoen.2021.106845
• Languages: English
• ISSNs: 2211-2855

Abstract

Abstract: Performances of plasmon-mediated optoelectronic devices are mainly limited by the transfer efficiency of the energetic hot electrons (QEHET ) from metallic nanostructures into the semiconductor active region. Here, we report a novel strategy to enhance the efficiency of plasmon-induced hot-electron transfer (PHET) across Au nanoparticles (NPs)/GaN film via the external-strain-induced piezo-phototronic effect. By performing transient absorption (TA) spectrum measurement of the Au NPs/GaN freestanding membrane under different strain conditions, the enhancement of effective QEHET is estimated to be nearly 120% under 3.57% compressive straining. This enhancement is comparable or better than previously reported achievement using other methods such as controlling the material's morphology or optimizing charge-transfer transition pathway. The mechanisms of the piezo-phototronic enhanced PHET rely on the modulated barrier height between Au NPs/GaN heterojunction. This was further confirmed by performing the photoresponse ability measurements in Au NPs/GaN film under external straining. Photoresponsivity of the plasmonic heterojunction is obviously increased/decreased when the hybrid membrane undergoes compressive/tensile strain. These results advance our understanding of the piezo-phototronic effect on QEHET in plasmonic heterostructures, and offer effective strategies to manipulate hot carrier dynamics for high-performance plasmonic devices and photoelectrochemical systems. Graphical Abstract: In this work, we report a novel efficient plasmonic hot-electron transfer enhancement strategy in Au/GaN heterojunction by the piezo-phototronic effect. The QEHET is modulated from nearly 89–120% under external strain. This technology offer effective strategies for preparation high-performance plasmon-driven devices and photoelectrochemical systems. ga1 Highlights: The piezo-phototronic effect is firstly used to modulate plasmon-induced hot-electron transfer across Au/GaN heterojunction. The QE HET is enhanced nearly 120% under the external compressive strain of 3.57%. The creative enhancement strategy indicate a huge potential in photosening, chemical synthesis and integrated photonics.