Development of Visible-to-Near Infrared Nanoplasmonics Using Metal & Heavily-Doped Semiconductor Nanoparticles

Localized surface plasmon resonance (LSPR) is observed when free carriers (electrons and holes) in nanoparticles oscillate collectively at a certain resonant wavelength of incident light. As a result of polarization caused by the collective oscillation of free carriers, an enhanced photoelectric field is induced in the vicinity of nanoparticles, and decays rapidly in the surrounding dielectric. This enhanced photoelectric field is concentrated in a small area beyond the diffraction limit of light, and has attracted attention in terms of enhancing the photochemical processes of nearby materials, enabling selection-rule breakdown, capturing molecules, and probing in vivo. Plasmon energy propagation and carrier transfer to nearby materials below the diffraction limit of light are other important applications of LSPR. The LSPR wavelength can be controlled by the dielectric constant of the material, the size and shape of the nanoparticles, the dielectric constant of the surrounding medium, free carrier density, plasmon coupling, and so on. Controlling the LSPR wavelength is an important issue in order to make full use of light, and nanoparticle shape and free carrier density can greatly change the LSPR wavelength among the above parameters.


Control over LSPR Wavelength and Optical Properties of Shape-Controlled Metal Nanoparticles


Simple Reductant Concentration-Dependent Shape-Control of Polyhedral Gold Nanoparticles and Their Plasmonic Properties
（Langmuir 2012, 28, 9021.）
One-Pot Controllable Synthesis of Au@Ag Heterogeneous Nanorods with Highly Tunable Plasmonic Absorption（Chem. Mater. 2013, 25, 2580.）
Visible to Near-Infrared Plasmon-Enhanced Catalytic Activity of Pd Hexagonal Nanoplates for the Suzuki Coupling Reaction
（Nanoscale 2015, 7, 12435.）

Control over LSPR Wavelength and NIR Light Energy Conversion Using Shape-Controlled Heavily-Doped Semiconductor Nanoparticles


Near Infrared Light Induced Plasmonic Hot Hole Transfer at a Nano-Heterointerface（Nat. Commun. 2018, 9, 2314.）
Clear and transparent nanocrystals for infrared-responsive carrier transfer（Nat. Commun. 2019, 10, 406.）
Plasmonic p-n Junction for Infrared Light to Chemical Energy Conversion （J. Am. Chem. Soc. 2019, 141, 2446. (Cover Picture)）

Acceleration of Photochemical Processes by Plasmonic Enhancement of Photoelectric Field


Carrier-selective Blocking Layer Synergistically Improves the Plasmonic Enhancement Effect （J. Am. Chem. Soc. 2019, 141, 8402. (Cover Picture)）