Enhanced Photoelectrocatalytic Reduction of Oxygen Using Au@TiO₂ Plasmonic Film

Abstract

Novel Au@TiO plasmonic films were fabricated by individually placing Au nanoparticles into TiO nanocavity arrays through a sputtering and dewetting process. These discrete Au nanoparticles in TiO nanocavities showed strong visible-light absorption due to the plasmonic resonance. Photoelectrochemical studies demonstrated that the developed Au@TiO plasmonic films exhibited significantly enhanced catalytic activities toward oxygen reduction reactions with an onset potential of 0.92 V (vs reversible hydrogen electrode), electron transfer number of 3.94, and limiting current density of 5.2 mA cm. A superior ORR activity of 310 mA mg is achieved using low Au loading mass. The isolated Au nanoparticle size remarkably affected the catalytic activities of Au@TiO, and TiO coated with 5 nm Au (Au@TiO) exhibited the best catalytic function to reduce oxygen. The plasmon-enhanced reductive activity is attributed to the surface plasmonic resonance of isolated Au nanoparticles in TiO nanocavities and suppressed electron recombination. This work provides comprehensive understanding of a novel plasmonic system using isolated noble metals into nanostructured semiconductor films as a potential alternative catalyst for oxygen reduction reaction.

Phase and Defect Engineering of MoS2 Stabilized in Periodic TiO2 Nanoporous Film for Enhanced Solar Water Splitting

“…The coexistence of MoS 2 and TiO 2 in the samples was confirmed by XPS survey scan (Figure S7a, Supporting Information). The XPS peaks of Ti and O are corroborated by the crystalline TiO 2 reported previously (Figure S7b,c, Supporting Information) . Two binding energy of S 2p (Figure S7d,e, Supporting Information) at 161.7 and 163.2 eV are assigned to the lattice S 2− in MoS 2 .…”

“…: 44‐1294) and anatase TiO 2 (PDF Card No. : 73‐1765) . A broad peak corresponding to an interlayer d‐spacing of MoS 2 (002) facets is identified at 14.48 o in the sample before hydrothermal treatment .…”

Hierarchical Multicomponent Inorganic Metamaterials: Intrinsically Driven Self‐Assembly at the Nanoscale

“…The isolated Au nanoparticle size remarkably affected the catalytic activities of Au@TiO 2 , and TiO 2 coated with 5 nm Au (Au 5 @TiO 2 ) exhibited the best catalytic function to reduce O 2. Reproduced with permission . Copyright 2016, American Chemical Society.…”

“…In addition to excellent performance, thus‐fabricated plasmonic metamaterials demonstrated desirable durability. The physical isolation of individual nAu particles within uniformly distributed TiO 2 nanocavities prevents electron recombination, thus supporting an increased availability of “hot” electrons to engage in plasmon‐enhanced oxygen reduction reactions …”

Enhanced Adsorption and Photocatalysis by Introduction of C into N, Zr/TiO2

“…Many elements have been investigated in this regard, including noble elements (Au, Ag, Pt, Rh), [1][2][3][4][5] transition metals (Zn, Fe, Ni, Cu, Co), [6][7][8][9][10] rare earth elements, [11] as well as other metals. [12,13] In view of the various characteristics of metals and non-metals, co-doping with these elements has also been explored, encompassing C, N, F, S, P, B, and metal elements.…”