Hot Carrier Lifetimes and Electrochemical Water Dissociation Enhanced by Nickel Doping of a Plasmonic Electrocatalyst

Abstract

Hot carriers generated by localized surface plasmon resonance (LSPR) excitation of plasmonic metal nanoparticles are known to enhance electrocatalytic reactions. However, the participation of plasmonically generated carriers in interfacial electrochemical reactions is often limited by fast relaxation of these carriers. Herein, we address this challenge by tuning the electronic structure of a plasmonic electrocatalyst. Specifically, we design an electrocatalyst for alkaline hydrogen evolution reaction (HER) that consists of nanoparticles of a ternary Cu−Pt−Ni ternary alloy. The CuPt alloy has both plasmonic attributes and electrocatalytic HER activity. Ni doping contributes an electron-deficient 3d band and fully filled 4s band, which promotes water adsorption and prolongs the lifetimes of excited carriers generated by plasmonic excitation. As an outcome, the Cu−Pt−Ni nanoparticles exhibit boosted activity for electrochemical water dissociation and HER under LSPR excitation.

Cu5FeS4 quantum dots as a single-component photo-assisted electrocatalyst for efficient hydrogen evolution

“…The photoactive components are usually used to absorb light to produce plasmonic hot electrons or photogenerated electrons and holes, which can be injected into the electrocatalytic components to improve the activity. [21][22][23] The related interfacial kinetics and mechanism are critical for promoting the activity and have been widely studied by various conventional characterization methods, such as band alignment, steady-state partial current density, and time-resolved photoluminescence spectroscopy. [24][25][26] However, the efficiency of the bi-component P-EC catalysts is still far below expectations due to the existence of heterointerfaces between the photo-and electrocomponents with abundant interfacial defects, unavoidable charge recombination, and multiple competing reaction pathways.…”

Efficient interfacial electron transfer induced by hollow-structured ZnIn2S4 for extending hot electron lifetimes

“…S29, ESI †), a double-exponential curve is obtained with t 1 and t 2 corresponding to electron-phonon and phonon-phonon scattering during the hot electrons relaxation in the LSPR effect. 12,34 The 1 ps time scale decay corresponds to the hot electrons formed by metal lattice heating through electronphonon scattering, and the decay on a longer time scale resulted from the phonon-phonon scattering of hot chargecarriers, which corresponds to dissipating heat-energy from the metal lattice to the surrounding medium for enhancing the reaction kinetics. [12][13][14]34 The t 1 and t 2 time constants of NCS/ZIS-NCs are 1.04 ps and 30.68 ps (Fig.…”

“…12,34 The 1 ps time scale decay corresponds to the hot electrons formed by metal lattice heating through electronphonon scattering, and the decay on a longer time scale resulted from the phonon-phonon scattering of hot chargecarriers, which corresponds to dissipating heat-energy from the metal lattice to the surrounding medium for enhancing the reaction kinetics. [12][13][14]34 The t 1 and t 2 time constants of NCS/ZIS-NCs are 1.04 ps and 30.68 ps (Fig. 5(c)), suggesting fast hot electron relaxation.…”

“…is being exploited for coupling with a photocatalyst to broaden the photoabsorption range, modulate the adsorption of intermediates, facilitate the bond dissociation and enhance the surface redox reactions through the action of hot carriers, charge polarization, and local heat. 12 The LSPR excitation leads to rapid radiative decay ( i.e. scattering) by the re-emission of phonons, and non-radiative decay.…”

Nano‐Impact Single‐Entity Electrochemistry Enables Plasmon‐Enhanced Electrocatalysis**

“…[6] Electron-electron scattering prompts thermalization of these energetic charge carriers, forming a "warm" Fermi-Dirac distribution. [7] Non-thermal and thermalized carriers have been shown to facilitate various electrocatalytic reactions such as glucose, [8,9] methanol, [10][11][12] and glycerol [13] oxidation, ammonia, [14] proton [12,15] and oxygen reduction. [16] Finally, the internal decay of hot carriers inside a plasmonic nanoparticle can significantly heat the nanostructure and surrounding environment.…”