Noble Metal Atoms Research Articles

Doping engineering modulated adsorption and sensing performance of β-tellurene towards greenhouse gas molecules

Abstract CO2, CH4, CF4, CCl3F, CCl2F2, HCF2Cl, N2O and SF6 are well-known greenhouse gases that cause serious threat to the earth's ecological environment. To expand the application and development of two-dimensional (2D) materials in the field of greenhouse gas sensing, adsorption of the greenhouse gases on the pristine β-tellurene monolayer was investigated by first-principles calculations to estimate the potential application of β-tellurene as a monitor for greenhouse gas. The results indicate that β-tellurene exhibits favorable adsorption capabilities for greenhouse gases, especially demonstrating selective sensing potential for SF6 molecules due to the changes in electronic structures after gas exposure. The effects of noble metal atoms doping on structural, electronic and SF6 sensing properties were systematic estimated. The calculation results revealed that doping with different transition metal (TM) atom could bring diverse electronic properties to β-tellurene. Among them, doping with Os, Pd, Pt, Rh, and Ru could effectively enhance the electronic delocalization, improving the detection sensitivity for β-tellurene. In addition, TM doping could also improve the recovery time of β-tellurene by two orders of magnitude, and provided the possibility for β-tellurene as a work function type sensing material. By delving into the gas sensing properties of β-tellurene with TM doping, we provided a valuable guidance for the design of innovative tellurene- based sensing 2D materials for devices and technologies.

First-principles design of PtPd bimetal dispersed WTe2 monolayer for sensing thermal runaway gases: Enhanced performance against single Pt or Pd dispersion

To conduct the early-monitoring of thermal runaway for the Li-ion battery (LIBs), this work purposes PtPd bimetal dispersed WTe2 (PtPd-WTe2) monolayer as a promising sensing material to realize the high-sensitive detection of thermal runaway gases (H2, CO, CO2, C2H2 and C2H4). The adsorption behavior of PtPd-WTe2 monolayer upon such five gas molecules are compared with single Pt- and Pd-dispersed WTe2 monolayer from the first-principles insight to highlight the combined catalytic property of two noble metal atoms. Results reveal that Pt-, Pd- and PtPd-WTe2 monolayer all behave good chemical and thermal stability at 498 K with good binding force between the noble metal atom(s) and the pristine WTe2 surface. Besides, PtPd-WTe2 monolayer behaves much enhanced adsorption performance with more negative adsorption energy and much higher sensing response with larger bandgap changing rate than Pt- and Pd-WTe2 monolayer upon five typical gas molecules. Moreover, the desorption property analysis manifests the necessity conducting the heating process to realize the reusability of PtPd-WTe2 monolayer for gas sensing. These findings manifest the strong potential of PtPd-WTe2 monolayer as a resistive gas sensor for detections of the thermal runaway gas species thus evaluating the operation status of the LIBs, which may stimulate the further deeper investigations about WTe2-based materials for gas sensing applications across multiple fields.

Noble metal-modified copper surfaces for alkaline condition hydrogen evolution reaction

Cu-based materials would be attractive candidates for cost-effective alkaline hydrogen evolution reaction (HER) electrocatalysts due to high abundance, excellent conductivity, and excellent stability in alkaline environments, if not for the inherent inertness of Cu in HER. This inertness has led to a relative lack of research on Cu-based HER catalysts in both experimental and theoretical domains. Here, We report engineered Cu(111) surfaces that can significantly improve the poor activity of H2O dissociation on pure Cu(111) surface. We do this by introducing noble metal atoms (M = Ru, Rh, Pd, Ag, Os, Ir, Pt) through surface doping. These modified surfaces exhibit excellent thermodynamic and electrochemical stability, with the exception of Cu(111)-Ag. Notably, the H2O dissociation energy barrier on Cu(111)-Os (Eb) is only 0.74 eV, which is much smaller than that (1.31 eV) of pure Cu(111), and is even lower than that of Pt (Eb = 0.92 eV), which is commercially used for electrodes. The low Eb and resulting expected excellent performance of Cu(111)-Os for water splitting is related to the particular local electronic properties of doped Os atoms, specifically the electronic structure of the Os d-orbitals, which have a d-band center near Fermi level (EF) and a high density of states around EF, including just above EF. These results are expected to stimulate the investigation of surface alloyed Cu, leading to a new direction for the design of high-performance and low-cost electrocatalysts.

MoS2 supported Ruthenium nanoparticles with abundant sulfur vacancies significantly improved hydrogen evolution reaction

The electrochemical hydrogen evolution reaction (HER) has become one of effective ways to produce hydrogen. MoS2 is a promising electrocatalyst for the HER, and loading noble metal atoms on MoS2 support can further enhance its HER activity. In present work, the CO was employed as a structure-directing agent to in situ synthesize MoS2-n (n = 0, 0.5, 1.0, 1.4 and 2.0 MPa, representing the CO pressure). Among them, the MoS2-1.4 with highest amounts of sulfur vacancies and superior alkaline HER performance was selected as the support for Ru loadings. Sulfur vacancies can stabilize Ru nanoparticles, prevent nanoparticles from aggregating, and facilitate the formation of small-sized nanoparticles. By optimizing the loading amounts of Ru, the 5Ru@MoS2-1.4 with the Ru loading of 5 wt.% and nanoparticle size of 2 nm exhibits the best alkaline HER activity by displaying a low overpotential of 55 mV and Tafel slope of 68.6 mV dec−1 at a current density of 10 mA cm−2 in 1.0 M KOH medium. This can be majorly related to the synergistic effect of MoS2-1.4 support and small-sized Ru nanoparticles, wherein the CO plays a significant role in regulating the structure of MoS2-1.4 support that favors dispersion of Ru nanoparticles. Generally, present work provides a strategy to enhance the HER catalytic performance of MoS2, which is favorable for other highly-efficient catalyst design.

Stable anchoring of single rhodium atoms by indium in zeolite alkane dehydrogenation catalysts.

Maintaining the stability of single-atom catalysts in high-temperature reactions remains extremely challenging because of the migration of metal atoms under these conditions. We present a strategy for designing stable single-atom catalysts by harnessing a second metal to anchor the noble metal atom inside zeolite channels. A single-atom rhodium-indium cluster catalyst is formed inside zeolite silicalite-1 through in situ migration of indium during alkane dehydrogenation. This catalyst demonstrates exceptional stability against coke formation for 5500 hours in continuous pure propane dehydrogenation with 99% propylene selectivity and propane conversions close to the thermodynamic equilibrium value at 550°C. Our catalyst also operated stably at 600°C, offering propane conversions of >60% and propylene selectivity of >95%.

Real-time tracking of three-dimensional atomic dynamics of Pt trimer on TiO2 (110).

Single and multi-atoms supported on oxide substrates ultimately increase the efficiency of noble metal atom use, and moreover, catalytic activity and selectivity are also improved substantially. However, single and multi-atoms are unstable under catalytic conditions, and these metal atoms spontaneously aggregate and grow into nanoparticles. Catalytic performance is strongly related to local atomic configurations, and hence, it is essential to determine the three-dimensional (3D) atomic structures of multi-atoms on the substrate and their structural dynamics. Here, we show the real-time tracking of the 3D structural evolution of a Pt trimer on TiO2 (110) substrate at a high temperature, using high-spatiotemporal-resolution scanning transmission electron microscopy, where sub-angstrom spatial resolution is maintained, while the temporal resolution reaches 40 milliseconds. With the aid of prior structural knowledge of a Pt trimer for 3D reconstruction, the present method could open the way to characterize in situ atomic-scale structural dynamics, especially meta-stable structural transition.

Charge State of Au Atoms on an Oxidized Rutile TiO2(110) Surface by AFM/KPFM at 78 K.

The charge state of noble metal atoms on a semiconductor surface is an important factor in surface catalysis. In this study, Au atoms were deposited on the rutile TiO2(110) surface to characterize its charge properties using atomic force microscopy with Kelvin probe force microscopy at 78 K. Au single atoms, dimers, and trimers at different sites on the surface were investigated. Positively charged Au atoms were verified at oxygen sites, while negatively charged Au atoms were found near oxygen vacancy sites. Furthermore, the charge states of small Au nanoclusters were clarified. Understanding the charge states of Au atoms is significant for identifying their efficient catalytic effects in surface catalysis.

Structural and optical properties of hybrid materials derived from gold nanoparticles in different polystyrene (PS)-b-poly(4-vinylpyridine) (P4VP) matrices

We introduce the preparation as well as the structural and optical properties of hybrid materials consisting of diblock copolymer matrices with gold nanoparticles. Anionically synthesized diblock copolymers of the PS-b-P4VP sequence, where PS: polystyrene and P4VP: poly(4-vinylpyridine) with well-defined characteristics were utilized as the polymer matrices. The specific pyridine-containing copolymers were selected due to their susceptibility to post-polymerization chemical modification reactions. Basic tertiary amines can be easily modified due to the presence of the nitrogen atom (N) in the 4-position (-para) of the aromatic ring in the monomeric units of poly(4-vinylpyridine). In this manner, the addition of either atoms or whole compounds as ion pairs is enabled. We report that the role of noble metal atoms in polymer matrices is dual. Firstly, microphase separation in the presence of heteroatoms occurs even in cases of extremely low molecular characteristics due to the increased repulsion between the components and secondly the excitation of plasmon resonance at the polymer/nanoparticle interface is induced. We believe that our work sheds light on the driving forces of self-assembly on the studied modified copolymers. The results strongly suggest that the hybrid materials can adopt well-defined morphologies even in very low molecular weights, a fact that renders them promising candidates for photonic applications.

Carbon Monoxide and Propylene Catalytic Oxidation Activity of Noble Metals (M = Pt, Pd, Ag, and Au) Loaded on the Surface of Ce0.875Zr0.125O2 (110)

With the advances in engine technology, the exhaust gas temperature of automobiles has further reduced, which in turn leads to an increase in the emissions of carbon monoxide (CO) and hydrocarbons (HCs). In order to understand the influence of CeO2-based catalysts loaded with different noble metals on the catalytic oxidation activity of CO and HCs, this study constructed catalyst models of Ce0.875Zr0.125O2 (100) surfaces loaded with Pt, Pd, Ag, and Au. The electronic density and state density structures of the catalysts were analyzed, and the reaction energy barriers for CO oxidation and C3H6 dehydrogenation oxidation on the catalyst surfaces were also calculated. Furthermore, the activity sequences of the catalysts were explored. The results revealed that after loading Pt, Pd, Ag, and Au atoms onto the catalyst surfaces, these noble metal atoms exhibited strong interactions with the catalyst surfaces, and electron transfer occurred between the noble metal atoms and the catalyst surfaces. Loading with noble metals can enhance the catalytic activity of CO oxidation, but it has little effect on the dehydrogenation oxidation of C3H6. Of the different noble metals, loading with Pd exhibits the best catalytic activity for both CO and C3H6 oxidation. This study elucidated the influence of noble metal doping on the catalytic activity of catalysts at the molecular level, providing theoretical guidance for the design of a new generation of green and efficient catalysts.

Metallic W/WO2 solid-acid catalyst boosts hydrogen evolution reaction in alkaline electrolyte

The lack of available protons severely lowers the activity of alkaline hydrogen evolution reaction process than that in acids, which can be efficiently accelerated by tuning the coverage and chemical environment of protons on catalyst surface. However, the cycling of active sites by proton transfer is largely dependent on the utilization of noble metal catalysts because of the appealing electronic interaction between noble metal atoms and protons. Herein, an all-non-noble W/WO2 metallic heterostructure serving as an efficient solid-acid catalyst exhibits remarkable hydrogen evolution reaction performance with an ultra-low overpotential of −35 mV at −10 mA/cm2 and a small Tafel slope (−34 mV/dec), as well as long-term durability of hydrogen production (>50 h) at current densities of −10 and −50 mA/cm2 in alkaline electrolyte. Multiple in situ and ex situ spectroscopy characterizations combining with first-principle density functional theory calculations discover that a dynamic proton-concentrated surface can be constructed on W/WO2 solid-acid catalyst under ultra-low overpotentials, which enables W/WO2 catalyzing alkaline hydrogen production to follow a kinetically fast Volmer-Tafel pathway with two neighboring protons recombining into a hydrogen molecule. Our strategy of solid-acid catalyst and utilization of multiple spectroscopy characterizations may provide an interesting route for designing advanced all-non-noble catalytic system towards boosting hydrogen evolution reaction performance in alkaline electrolyte.

Noble metal single-atom catalyst supported by C[formula omitted]N[formula omitted] monolayer as a promising reduction electrocatalyst for low-density environmental NO

Here, we show that the noble metal atoms decorated over the porous monolayer of C8N8 demonstrate superior performance in the reduction reaction of low-density environmental NO gas. Among different considered single-atom catalysts (SAC), the osmium atom exhibits the most energetically favored NO-reduction pathway with the free energy change of −12.71 eV even at low NO coverage. Both nitrogen- and carbon-dominated large rings are capable of adsorbing NM atoms to form NM@C8N8 configurations. Fortunately, no clustering resulted for the noble metal atoms anchored onto the pristine C8N8 due to the substantial binding energy of −12.87 eV. The considered SACs exhibit their electrocatalytic activities by the dominant contribution to the total DOS around the Fermi level, especially for the Os, Ir, and Rh adatoms. At low NO coverage, NOER over Os@C8N8 proceeds the downhill profile diagram and demonstrates promising electrocatalytic performance in NO-reduction. Similarly, at high NO coverage, N2O2 can be adsorbed by NM@C8N8, due to the negative value of the free energy change.

The electronic and optical properties, gas sensor and NO removal application investigations of noble metal-adsorbed MoSi2N4

In this paper, the electronic and optical properties, gas sensor behavior and photocatalytic nitric oxide (NO) removal applications of noble metal-adsorbed MoSi2N4 (NMs-MSN, NMs = Au, Ag, Cu, Pd and Pt) are investigated and screened based on first-principles calculations. The band gaps of MoSi2N4 decrease to different degrees after noble metals are adsorbed, especially when the band gap changes from intrinsic MoSi2N4 of 1.89 eV to Pd-MoSi2N4 of 1.59 eV. Based on density of states (DOS) analysis, new degenerate energy bands formed and combined with the valence band after Pd adsorbed, which resulted in a band gap decrease. The optical property calculations show that the light absorption range and coefficient of NMs-MSN significantly increase. Then, the sensor behaviors are investigated and screened based on the adsorption and recovery behaviors of gas molecules (including NO, CO, O2, CO2, NO2, H2O, H2S and NH3) on NMs-MSN. Based on the adsorption energy, recovery time and band gap changes after gas adsorption, it can be concluded that Ag-MSN is suitable for sensing SO2 molecules, that Au-MSN is suitable for sensing SO2, CO and O2 molecules, and that Pd-MSN is suitable for sensing N2, NO and NO2 molecules. The most suitable noble-metal atoms for the photocatalytic removal of NO are calculated and screened, and the Pd-MSN is determined to be most suitable for NO removal. The introduction of a Pd atom inhibits desorption of the toxic product nitrogen dioxide (NO2), inducing the main product to become a nitrate ion (NO3−). The mechanism indicates that the potential barrier is greatly reduced because electron-hole complexation is suppressed. In general, noble metal atom-adsorbed MoSi2N4 can effectively change the band gap, improve the light absorption coefficient, adjust the gas sensor behavior, and enhance the photocatalytic ability for NO removal.

Vertex‐Shared Linear Superatomic Molecules: Stepping Stones to Novel Materials Composed of Noble Metal Clusters

Extremely small metal clusters composed of noble metal atoms (M) have orbitals similar to those of atoms and therefore can be thought of as artificial atoms or superatoms. If these superatoms can be assembled into molecular analogs, it might be possible to create materials with new characteristics and properties that are different from those of existing substances. Therefore, the concept of superatomic molecules has attracted significant attention. The present review focuses on vertex‐shared linear M12n+1 superatomic molecules formed via the sharing of a single metal atom between M13 superatoms having icosahedral cores and summarizes the knowledge obtained to date in this regard. This summary discusses the most suitable ligand combinations for the synthesis of M12n+1 superatomic molecules along with the valence electron numbers, stability, optical absorption characteristics, and luminescence properties of the M12n+1 superatomic molecules fabricated to date. This information is expected to assist in the production of many M12n+1 superatomic molecules with novel structures and physicochemical properties in the future.

Structural, electronic, nonlinear optical properties and spectroscopic study of noble metals doped C60 fullerene using M06-2X

Structural, electronic, and nonlinear optical (NLO) properties of noble metals doped fullerenes (C60) were investigated using DFT calculations. The thermodynamic stability results reveal the stability of pristine and dopedC60 structures. The doping of C60nanocage with Ag, Au, and Pt atoms results in an increase in the reactivity with a charge transfer from carbon to noble metal atoms. The molecular reactivity descriptors show that PtC59is the softest (S = 0.74 eV) compound with a high electrophilicity (ω = 18.36 eV) and lower gap energy (Eg = 2.69 eV). The QTAIM calculations indicate that the dopant atoms are bounded to the adjacent carbon atoms through partially covalent bonds. The TD-DFT analysis proves that the maximum absorption wavelength is achieved with PtC59. In addition, doping enhances the NLO properties where a maximum first hyperpolarizability value (1.1 × 104 au) was observed for PtC59 and the doped fullerene surface becomes more optically active.

On the Nature of the Partial Covalent Bond between Noble Gas Elements and Noble Metal Atoms

This article provides a discussion on the nature of bonding between noble gases (Ng) and noble metals (M) from a quantum chemical perspective by investigating compounds such as NgMY (Y=CN, O, NO3, SO4, CO3), [NgM-(bipy)]+, NgMCCH, and MCCNgH complexes, where M=Cu, Ag, Au and Ng=Kr-Rn, with some complexes containing the lighter noble gas atoms as well. Despite having very low chemical reactivity, noble gases have been observed to form weak bonds with noble metals such as copper, gold, and silver. In this study, we explore the factors that contribute to this unusual bonding behavior, including the electronic structure of the atoms involved and the geometric configuration of the concerned fragments. We also investigate the metastable nature of the resulting complexes by studying the energetics of their possible dissociation and internal isomerization channels. The noble gas-binding ability of the bare metal cyanides are higher than most of their bromide counterparts, with CuCN and AgCN showing higher affinity than their chloride analogues as well. In contrast, the oxides seem to have lower binding power than their corresponding halides. In the oxide and the bipyridyl complexes, the Ng-binding ability follows the order Au > Cu > Ag. The dissociation energies calculated, considering the zero-point energy correction for possible dissociation channels, increase as we move down the noble gas group. The bond between the noble gases and the noble metals in the complexes are found to have comparable weightage of orbital and electrostatic interactions, suggestive of a partial covalent nature. The same is validated from the topological analysis of electron density.

First principles calculations of electronic and optical properties of InSe nanosheets doped with noble metal atoms

Monolayer Indium Selenide (ML-InSe) is studied for 4x4 supercell structure through ab initio calculations. The electronic and optical properties of ML-InSe for both pristine and substitutional doped ML-InSe with Palladium (Pd), Platinum (Pt), Silver (Ag), and Gold (Au) atoms have been calculated. With substitutional doping, ML-InSe has been observed to have a spin-dependent electronic structure. The flat energy bands near the Fermi level are observed in ML-InSe with doping elements placed in In site. The flat bands of d orbitals of some noble metal atoms are formed by the projected density of states (PDOS). The PDOS calculations show that the s-orbital of In and p-orbital of Se form the conduction band edge. The energetically favorable position of doping atoms is found to be the PtIn substitution atom according to formation energy calculations. For each studied structure, the bond length of the first neighbor of doping atoms in doped ML-InSe, static dielectric constant (ε0), refractive index, and energy band gap have been calculated. In the structure ML-InSe with AuSe, ε0 reaches ∼ 8.15. Another important result is that substitutional doping induces some peaks in the lower energy region of the imaginary part of the dielectric function. These peaks mainly refer to the absorption in related regions and may be important for the optoelectronic properties of ML-InSe.

Theoretical insights into nonmetal-doped graphyne-supported noble metal electrocatalysts for NH3 synthesis via nitrogen reduction

NH3 is a valuable chemical in the agricultural and industrial fields, and a potential carbon-free energy carrier because of its high hydrogen capacity and energy density. Currently, industrial-scale NH3 synthesis is based on the Haber–Bosch process; however, this process consumes large amounts of energy and causes serious pollution. Therefore, new synthetic methods are necessitated for the production of NH3. The electrocatalytic nitrogen reduction reaction (NRR) can be conducted for NH3 production under ambient conditions and is expected to overcome the problems associated with the current processes. Herein, we designed a series of single-atom catalysts for noble metal (NM = Ru, Rh, Pd, Os, Ir, Pt) atoms anchored on non-metallic atom (X = B, N, O)-doped graphyne (NMX@GY) and investigated their effects on NRR performance using density functional theory calculations. It was concluded that RuB@GY and OsB@GY exhibited the highest NRR performance following the distal pathway; they had limiting potentials of −0.458 and −0.323 V and could effectively inhibit competing hydrogen evolution reactions. Furthermore, the high catalytic activity of RuB@GY and OsB@GY was attributed to their electronic structures. This study provides a new strategy for the study of carbon-based electrocatalysts with high activity, selectivity, and stability for NH3 synthesis.

Noble-metal single atom with non-metal co-doped graphene: First-principles investigation of structures, electronic and magnetic properties

The geometric, electronic, and magnetic properties of noble-metal single atom (M = Rh, Pd, Ag, Ir, Pt, and Au) with non-metal (X = B, C, N, and O) co-doped graphene (referred to as MX4-G) were thoroughly investigated by using first-principle calculations. Our results demonstrate that Rh, Pd, Ir, Pt, and Au individual atoms cannot be strongly bonded with O4-G substrate to form MO4-G, and Ag atom cannot be stably anchored on all X4-G substrates. The stable MX4-G structures in which the lost charges of M atom change with the electronegativity of X atom may exhibit different catalytic activity and selectivity. The ferromagnetic couplings are observed in RhC4-G, RhN4-G, IrC4-G, and IrN4-G through spin density analysis, and five different up- and down-spin d orbitals of Rh and Ir atoms should be responsible for the local magnetic moments. The MX4-Gs can exhibit metallic, half-metallic, or semiconductor behaviors because their band gaps are sensitively dependent on the atomic types of M and X. Our work provides fundamental insights into the applications of MX4-G nanomaterials in various catalytic reactions and novel spintronic devices.

First-principles study of noble metal atom doped Fe(100) as electrocatalysts for nitrogen reduction reaction

NH3 is one of the most important chemicals on earth and can be used as a chemical feedstock, agricultural fertilizer and hydrogen-rich carrier. Recently, the technology of NH3 synthesis by electrochemical nitrogen reduction reaction (NRR) has attracted extensive attention. The core problem of the NRR is the development of electrocatalysts with high activity, selectivity and stability. Fe is not only a constituent element of biological nitrogenase, but also a widely used catalyst material in industrial NH3 synthesis. Due to the presence of unoccupied orbitals, it shows some potential in the process of N2 adsorption and desorption. Therefore, the catalytic activity of Fe(100) for the NRR was studied based on density functional theory, and the electronic properties of Fe(100) were regulated by doping noble metal (NM= Ru, Rh, Pd, Os, Ir, Pt) atoms to reduce the energy barrier and enhance the activity and selectivity of the catalyst. Through the screening of three important processes including N2 adsorption and activation, N2H formation and NH3 desorption, the catalytic activity of Ir atom doped Fe(100) (Ir@Fe(100)) was the highest, and the energy barrier of first hydrogenation step was 0.342 eV. More importantly, Ir@Fe(100) can significantly inhibit the hydrogen evolution reaction. This study can provide some theoretical reference and guidance for the design and preparation of Fe-based catalysts.

Au Single Atom Supported on TiO2 Drives Hole Mitigation for the Enhanced Photooxidation of Hg0

Noble metal-supported TiO2 has excellent photocatalytic activity for the oxidation of Hg0 due to the Mott–Schottky barrier that prevents the recombination of photogenerated hole–electron pairs. However, surface noble-metal atoms usually cause low atomic utilization, of which the inner layer cannot participate in the oxidation and is hence not beneficial for improving the photocatalytic activity. Single-atom-based catalysts (SAC) have an extreme atomic efficiency, reducing the amount of noble metals and significantly improving photocatalytic activity. Herein, 0.1% Au single atom (SA)-doped Ti4+ defect TiO2 (0.1% Au–Ti1-xO2) with Au–(O)4 coordination was used for the photooxidation of Hg0. Second, the influence of the coordination on the separation of photogenerated electron–hole pairs, the transfer direction of charges, and the oxidation of Hg0 was thoroughly explored using transient photovoltage (TPV), in situ X-ray photoelectron spectroscopy (XPS), density functional theory (DFT), etc. Finally, the influence of SO2 and NO on the photooxidation of Hg0 was discussed using in situ diffuse reflection infrared Fourier transform spectroscopy (DRIFTS). 0.1% Au–Ti1-xO2 had a much higher photooxidation efficiency of Hg0 than 0.1% Au/TiO2. Moreover, the Au–(O)4 coordination significantly promoted the separation of photogenerated electron–hole pairs by driving the mitigation of photogenerated holes. Additionally, 0.1% Au–Ti1-xO2 exhibited a remarkable resistance to SO2 and NO because Au SA effectively avoided the deposition of nitrates and sulfates. This study provides a valuable surface engineering strategy for the atomic-level dispersion of noble metal-modified TiO2.