Rational design of bimetallic photocatalysts based on plasmonically-derived hot carriers

Abstract

Boosting hot-electron extraction for photochemistry: triple role of surface morphology of SiO2–Au–Pt plasmonic hetero-nanostructures.

Surface plasmon-driven photoelectrochemical water splitting of a Ag/TiO2 nanoplate photoanode

“…Under visible light irradiation, the incident light coincides with the localized surface plasmon resonances (LSPR) of the plasmonic Ag NPs and consequently the hot electrons near the Fermi level (E F ) are generated and excited to the higher-energy states. These hot electrons with sufficient energy overcome the Schottky barrier formed at the interface between Ag and TiO 2 which can signicantly retard the recombination of electron-hole pairs, 54,73 move to the conduction band of TiO 2 , and nally transfer to the Pt counter electrode via an external circuit for hydrogen production. And the photogenerated holes can participate in the water oxidation process or O 2 evolution.…”

Molecular Plasmonics with Metamaterials

“…473−477 A plasmonic hotcarrier catalytic system based on silica nanoparticles decorated with plasmonic gold nanoparticles and platinum nanoclusters was developed which exhibits enhanced plasmon-induced photodegradation of methylene blue dyes that outperforms other photocatalysts. 477 In addition to optical excitation by light illumination, hot electrons can also be generated electrically by tunneling electrons in tunnel junctions. 478,479 Recent realization of the electrically driven plasmonic nanorod metamaterial provides the opportunity to use an electron tunneling effect for the simultaneous excitation of hot electrons and surface plasmons, 119,480 opening a way to realize a new kind of hotelectron-activated nanoreactors, as well as highly compact and sensitive plasmonic sensors.…”

“…Plasmonic metamaterials in a colloidal form, which have advantages such as broadband absorption, easy fabrication, and high surface-to-volume ratio, have also been investigated for hot-carrier-based nanochemistry. − A plasmonic hot-carrier catalytic system based on silica nanoparticles decorated with plasmonic gold nanoparticles and platinum nanoclusters was developed which exhibits enhanced plasmon-induced photodegradation of methylene blue dyes that outperforms other photocatalysts …”

Tale of Two Resonances: Waveguide–Plasmon Coupling and High Q-Factor Engineering on the Nanoscale

“…Metallic nanoparticles (MNPs) with typical sizes larger or comparable to the metal skin depth support LSPs and enable the near-field enhancement and extreme confinement of an incident optical field. Various nanostructured noble metals, such as gold, silver, platinum, etc., in the shapes of spheres, rods, cubes, triangles, and stars have been fabricated to achieve a required plasmonic response at the wavelengths ranging from the UV to the near-infrared. − In addition, metallic core–shell constructs and nanoparticle assemblies have proven to sustain more versatile LSP modes and endow more degrees of freedom in tailoring the light–matter interactions at the nanoscale. − Typically, the LSP-induced near-field intensity enhancement for a single MNP, that is, | E | 2 /| E 0 | 2 , where E 0 and E are the electric field amplitudes of the incoming light and the local field at the surface of the MNP, respectively, can vary from ten-folds to thousand-folds, depending on its size and shape. ,− Larger enhancement factors can be obtained by delicately assembling MNPs into clusters or arrays. , Figure a–d illustrates the electric near-field intensity enhancement profiles of several classical LSP-resonant metal nanostructures, exhibiting hot spots with extremely localized near-fields under the excitation of their dipolar plasmon resonance modes.…”