Abstract

Localized surface plasmon resonance (LSPR)-induced hot-carrier transfer is a key mechanism for achieving artificial photosynthesis using the whole solar spectrum, even including the infrared (IR) region. In contrast to the explosive development of photocatalysts based on the plasmon-induced hot electron transfer, the hole transfer system is still quite immature regardless of its importance, because the mechanism of plasmon-induced hole transfer has remained unclear. Herein, we elucidate LSPR-induced hot hole transfer in CdS/CuS heterostructured nanocrystals (HNCs) using time-resolved IR (TR-IR) spectroscopy. TR-IR spectroscopy enables the direct observation of carrier in a LSPR-excited CdS/CuS HNC. The spectroscopic results provide insight into the novel hole transfer mechanism, named plasmon-induced transit carrier transfer (PITCT), with high quantum yields (19%) and long-lived charge separations (9.2 μs). As an ultrafast charge recombination is a major drawback of all plasmonic energy conversion systems, we anticipate that PITCT will break the limit of conventional plasmon-induced energy conversion.

Highlights

  • Localized surface plasmon resonance (LSPR)-induced hot-carrier transfer is a key mechanism for achieving artificial photosynthesis using the whole solar spectrum, even including the infrared (IR) region

  • The X-ray diffraction (XRD) patterns in Fig. 1f clearly show that the CdS/CuS heterostructured nanocrystals (HNCs) were composed of hexagonal covellite CuS (cv-CuS, Joint Committee on Power Diffraction Standards (JCPDS) no. 06–0464) and wurtzite CdS (w-CdS, JCPDS no. 89–944) phases, with the Cd/Cu molar ratio determined as 38:62 by X-ray fluorescence (XRF) spectroscopy

  • The high-resolution transmission electron microscopy (TEM) (HRTEM) image in Fig. 1c shows the high crystallinity of the CdS/CuS HNCs and the different lattice fringes corresponding to w-CdS (10–10) and cv-CuS (10–10) lattices

Read more

Summary

Introduction

Localized surface plasmon resonance (LSPR)-induced hot-carrier transfer is a key mechanism for achieving artificial photosynthesis using the whole solar spectrum, even including the infrared (IR) region. We elucidate LSPR-induced hot hole transfer in CdS/CuS heterostructured nanocrystals (HNCs) using time-resolved IR (TR-IR) spectroscopy. For heterostructured nanocrystals (HNCs) composed of plasmonic copper sulfide (CuS) phase and another metal or semiconductor phase (for example, acceptor phase), hot hole transfer has been proposed as a possible mechanism for providing IR-induced catalytic activity. The PITCT of CdS/CuS HNCs achieves high quantum yields (19%) and long-lived charge separations (9.2 μs), which has not been observed in plasmoninduced carrier-injection systems. Because ultrafast charge recombination is a major drawback of all plasmonic energy conversion systems, the PITCT mechanism proposes here should change the conventional consensus regarding LSPR-induced energy conversion due to the overwhelming advantage of high hot carrier transfer efficiency caused by in situ trapping of hot carriers and long-lived charge separation

Methods
Results
Conclusion
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call