Enhancement of Plasmon‐Induced Photoelectrocatalytic Water Oxidation over Au/TiO₂ with Lithium Intercalation

Abstract

Plasmon-induced chemical reaction is an emerging field but its development faces huge challenges because of low quantum efficiency. Herein, we report that the solar energy conversion efficiency of Au/TiO 2 in plasmon-induced water oxidation is greatly enhanced by intercalating Li + into TiO 2 . An incident photon-to-current efficiency as high as 2.0 %@520 nm is achieved by Au/Li 0.2 TiO 2 in photoelectrocatalytic water oxidation, realizing a 33-fold enhancement in photocurrent density compared with Au/TiO 2 . The superior photoelectrocatalytic performance is mainly ascribed to the enhanced electric conductivity and higher catalytic activity of Li 0.2 TiO 2 . Furthermore, the ultrafast transient absorption spectroscopy suggests that lithium intercalation into TiO 2 could change the dynamics of hot electron relaxation in Au nanoparticles. This work demonstrates that intercalation of alkaline ions into semiconductors can promote the charge separation efficiency of the plasmonic effect of Au/TiO 2 .

Dual heterojunction-based Au@TiO2photoelectrode exhibiting efficient charge separation for enhanced removal of organic dye under visible light

“…4c further depicts the electron lifetimes (τ) by normalizing the open-circuit potential (V oc ) curves. 39 Au@A-FH TiO 2 /Ti exhibits prolonged lifetime than that of A-FH TiO 2 /Ti and Au@A-TiO 2 /Ti under the same V oc . As displayed in Fig.…”

Sodium-Directed Photon-Induced Assembly Strategy for Preparing Multisite Catalysts with High Atomic Utilization Efficiency

“…However, the redispersion of Au single atoms in SC-Au/TiO 2 and SC-Au/O v -TiO 2 causes a negative bleach signal below the wavelength of 550 nm, which is indicative of the depletion of plasmon on electrons contributed by the interband transition of self-assembled Au nanoclusters. 48,49 Furthermore, the transient absorption assigned to photoelectrons in the photoreconstructed samples exhibits an obvious increase in the signal amplitude, especially for the SC-Au/O v -TiO 2 at wavelength >620 nm. This is believed due to the transient accumulation of electrons after the donation of electrons from Au clusters to TiO 2 with the assistance of interfacial electric fields and oxygen vacancies.…”

Active Site Engineering on Plasmonic Nanostructures for Efficient Photocatalysis

“…Based on the results of photodeposition and surface photovoltage imaging, the authors proposed that plasmonic hot holes were mainly concentrated near the metal/semiconductor interface, which is further pointed out as the active site (Ti–O–Au) for plasmon-driven H 2 O oxidation. Based on this understanding, the same group further proposed a series of strategies (e.g., Au dimer/TiO 2 , Ag x Au 1– x /TiO 2 , Au/Al 2 O 3 /TiO 2 , and Au/Li 0.2 TiO 2 ) to modify the plasmonic metal/TiO 2 interface for promoted H 2 O oxidation. − …”