Defect Effects on TiO₂ Nanosheets: Stabilizing Single Atomic Site Au and Promoting Catalytic Properties

Abstract

Isolated single atomic site catalysts have attracted great interest due to their remarkable catalytic properties. Because of their high surface energy, single atoms are highly mobile and tend to form aggregate during synthetic and catalytic processes. Therefore, it is a significant challenge to fabricate isolated single atomic site catalysts with good stability. Herein, a gentle method to stabilize single atomic site metal by constructing defects on the surface of supports is presented. As a proof of concept, single atomic site Au supported on defective TiO nanosheets is prepared and it is discovered that (1) the surface defects on TiO nanosheets can effectively stabilize Au single atomic sites through forming the Ti-Au-Ti structure; and (2) the Ti-Au-Ti structure can also promote the catalytic properties through reducing the energy barrier and relieving the competitive adsorption on isolated Au atomic sites. It is believed that this work paves a way to design stable and active single atomic site catalysts on oxide supports.

Heterogeneous Single Atom Electrocatalysis, Where “Singles” Are “Married”

“…Some of these methods are more appropriate to prepare SACs with a low metal loading content. As a typical example, Li and co‐workers recently reported Au single atoms supported on defective TiO 2 nanosheets with a mass percentage of 0.25% ( Figure 3 a) . During the synthesis process, the Au precursor was first dispersed on the defective TiO 2 nanosheets through a deposition–precipitation process, followed by reduction in a H 2 /Ar atmosphere to form isolated Au atoms (Figure b,c).…”

Macroscopic Spontaneous Polarization and Surface Oxygen Vacancies Collaboratively Boosting CO2 Photoreduction on BiOIO3 Single Crystals

“…BIO‐LOV2 shows a significant EPR signal at g = 2.003, which is the characteristic signal of e − trapped in OVs (Figure 2h). For further confirmation, synchrotron‐based X‐ray absorption spectroscopy (XAS) was conducted. In contrast to BIO‐L, the I L‐edge of BIO‐LOV2 shows a slight shift to lower energy, implying the valence state variation from I 5+ to I (5− x ) (inset of Figure 2i).…”

Interfacial CoOx Layers on TiO2 as an Efficient Catalyst for Solvent‐Free Aerobic Oxidation of Hydrocarbons

“…The D 2 -reduction test is more sensitive than the H 2 -TPR test and enables the detectiono fr educible oxygen species at al ower temperature. [7][8][9][10]59] Figure 6A shows the CO conversion rate as af unctiono ft emperature over layer-CoO x /TiO 2 and NP-CoO x /TiO 2 catalysts. Figure 5A shows the D 2 Om ass spectra observed over layer-CoO x /TiO 2 sample at various temperatures.…”

“…[1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] The interface between the metal oxide and the active sites is crucial for the adsorption/activation of reactants/intermediates, and the improvedp erformancec an be appliedt oc atalyzev arious industrial reactions such as CO 2 reduction, [1,2] water-gas shift, [3,4] CO oxidation, [7][8][9][10] methane reforming, [11][12][13] and Fischer-Tropsch synthesis. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] The interface between the metal oxide and the active sites is crucial for the adsorption/activat...…”