Exposed Crystal Facets Research Articles

Salt-induced anisotropic SrTiO3 to boost piezo-photocatalytic processes

Piezo-photocatalysis materials that can combine the piezoelectric effect in photocatalytic processes are very attractive for promising applications in water splitting and contaminant degradation. The perovskite oxides with adjustable exposed crystal facets are expected to optimize the catalysis activities by exposing the high-energy planes. In this work, we develop a salt-assisted strategy that controllably prepares anisotropic SrTiO3 particles with a large number of surface defects, which exhibit good piezo-photocatalytic features. The exposure of the crystal facets can be tuned by changing the assistants (NaCl or SrCl2). The SrCl2 can lead to the exposure of the (110) plane in one-dimensional SrTiO3 particles and NaCl can induce the cubic SrTiO3 particles with the exposure plane of (200). Attributed to the exposed high-energy facets and abundant oxygen vacancies, the latter show higher activities than the former in both water splitting and dye degradation under light irradiation and ultrasonic vibration. Our work provides an approach to optimize piezo-photocatalytic activities by tuning the exposed crystal facets.

Crystal facet-modulated CuO/CeO2 catalysts for highly selective catalytic reduction of NO by CO

The selective catalytic reduction of NO by CO (CO-SCR) has a significant impact on the sustainable development of the environment. It is crucial to design efficient low-temperature catalysts to overcome the challenges associated with the industrialization of CO-SCR. Herein, we present CuO/CeO2 catalysts with three different exposed crystal facets of CeO2 ((100), (110), and (111)) synthesized by a hydrothermal method followed by impregnation for CO-SCR. Among the three CuO/CeO2 catalysts, CuO loaded on rod-like CeO2 catalyst (CuO/CeO2-R) with exposed CeO2 (110) crystal facet showed the highest catalytic performance in the CO-SCR reaction, achieving complete conversion of NO and 99 % conversion of CO at 250 °C. A series of characterizations reveal that the interaction between CuO and CeO2 with different crystal facets is crucial to regulating the interface structure and oxygen vacancy (Ov) content. During in situ DRIFTS analysis, it was found that the primary adsorption sites for CO are the Cu+-Ov-Ce3+ interface sites. The CuO/CeO2-R catalyst had the highest number of these sites. Furthermore, CuO/CeO2-R contained many Ov sites, which promote NO dissociation and enhance its catalytic efficiency. This study offers insights into CO-SCR catalysis and the design of efficient catalysts by manipulating the exposed crystal facets of support to enhance CO-SCR activity.

Exploring the Facet-Dependent Structural Evolution of Pt/CeO2 Catalysts Induced by Typical Pretreatments for CO Oxidation.

Atomic-scale insights into the interactions between metals and supports play a crucial role in optimizing catalyst design, understanding catalytic mechanisms, and enhancing chemical conversion processes. The effects of oxide support on the dynamic behavior of supported metal species during pretreatments or reactions have been attracting a lot of attention; however, very less systematic integrations are carried out experimentally using real catalysts. In this study, we here utilized facet-controlled CeO2 as examples to explore their influence on the supported Pt species (1.0 wt %) during the reducing and oxidizing pretreatments that are typically applied in heterogeneous catalysts. By employing a combination of microscopy, spectroscopy, and first-principles calculations, it is demonstrated that the exposed crystal facets of CeO2 govern the evolution behavior of supported Pt species under different environmental conditions. This leads to distinct local coordinations and charge states of the Pt species, which directly influence the catalytic reactivity and can be leveraged to control the catalytic performance for CO oxidation reactions.

Modulation of the Intrinsic Radical Scavenging Properties of CeO2 Nanoparticles

Cerium dioxide (CeO2) has been extensively investigated as a scavenger of reactive oxygen radicals, particularly in the context of polymer electrolyte membrane fuel cells. This study focuses on elucidating the impact of exposed crystal facets of CeO2 nanoparticles on their radical scavenging activities. The manipulation of crystal shapes, including rod, cube, and octahedral forms, allows for controlled variation of the exposed crystal facets of CeO2 NPs. Characterization of the resulting CeO2 NPs is conducted using XRD, Raman spectroscopy, XPS, BET, and Fenton’s reaction. The research reveals that the intrinsic radical scavenging activity of CeO2 NPs can be effectively modulated by controlling their exposed crystal facets.

The influence of crystal facet on the catalytic performance of MOFs-derived NiO with different morphologies for the total oxidation of propane: The defect engineering dominated by solvent regulation effect

Crystal facet and defect engineering are crucial for designing heterogeneous catalysts. In this study, different solvents were utilized to generate NiO with distinct shapes (hexagonal layers, rods, and spheres) using nickel-based metal-organic frameworks (MOFs) as precursors. It was shown that the exposed crystal facets of NiO with different morphologies differed from each other. Various characterization techniques and density functional theory (DFT) calculations revealed that hexagonal-layered NiO (NiO-L) possessed excellent low-temperature reducibility and oxygen migration ability. The (111) crystal plane of NiO-L contained more lattice defects and oxygen vacancies, resulting in enhanced propane oxidation due to its highest O2 adsorption energy. Furthermore, the higher the surface active oxygen species and surface oxygen vacancy concentrations, the lower the C−H activation energy of the NiO catalyst and hence the better the catalytic activity for the oxidation of propane. Consequently, NiO-L exhibited remarkable catalytic activity and good stability for propane oxidation. This study provided a simple strategy for controlling NiO crystal facets, and demonstrated that the oxygen defects could be more easily formed on NiO(111) facets, thus would be beneficial for the activation of C−H bonds in propane. In addition, the results of this work can be extended to the other fields, such as propane oxidation to propene, fuel cells, and photocatalysis.

PH-dependent growth of alumina nanorods with a high aspect ratio for enhanced propane dehydrogenation performance

Controllable synthesis of porous alumina is always challenging due to the diversity of precursors and the complexity of the growth process. In this work, alumina nanorods with adjustable aspect ratios were synthesized by precipitation to investigate the morphology evolution mechanism related to aging pH, and the structure–activity relationship of alumina. The evolution path of precursors ammonium aluminum carbonate hydroxide (NH4Al(OH)2CO3, AACH) was established by tracking the variation in electrical charges and nitrate concentration during the growth process. It was revealed that the anisotropic adsorption of ions on the AACH crystal facets can modulate the axial and radial growth rates of the microcrystalline rods, regulating the one-dimensional oriented assembly of AACH. Alumina synthesized at pH 9.5 exhibited more exposition of (100) facets due to its higher aspect ratio, resulting in an aluminum content of up to 30% in the five-coordinated state. Due to the presence of strong metal-support interactions, the corresponding PtSn/Al2O3 catalyst demonstrated good propane dehydrogenation activity and stability, with propylene formation with 99% selectivity within 30 h of reaction. This study highlighted the significance of pH regulation in the growth environment of AACH, enabling the selective exposure of crystal facets in the alumina support, and providing an effective pathway to obtain highly active and stable catalysts.

Reduced graphene oxide encapsulated octahedral NiSe2 nanocrystals with dominant {111} crystal facets for efficient hydrogen evolution reaction

Regulating the exposed crystal facets of electrocatalysts is an effective means to enhance their electrocatalytic activity. However, related studies have focused mainly on traditional noble metals or metal oxides based electrocatalysts, while the research on crystal facets dependent electrocatalytic activity of metal selenides is still very rare. Here, crystal facets effect of cubic NiSe2 in electrocatalytic HER was studied. It was shown that octahedral NiSe2 nanocrystals dominated by active {111} crystal facets exhibited significantly enhanced HER activity. Moreover, by encapsulating the octahedral NiSe2 nanocrystals into reduced graphene oxide (rGO) nanosheet networks, further improvement in their HER activity could be achieved. First principles calculations and experimental characterization indicated that {111} crystal facts of NiSe2 had abundant surface active sites and ideal catalytic reaction energy barriers. This study not only expands the research on crystal facets-dependent HER activity, but also gains a deep understanding of the electrocatalytic mechanism.

In Situ Photodeposition of Gold Nanoparticles with Exposed High-Activity Crystal Facets under Different Sacrificial Agents.

In situ photodeposition presents a powerful approach for integrating noble metal co-catalysts onto semiconductor surfaces. However, achieving precise control over the microstructure of the deposited co-catalyst remains a major challenge. Au nanoparticles (NPs) are deposited onto H-KCNO using HAuCl4 in the presence of various sacrificial agents in this study. Notably, the choice of sacrificial agent decisively influences the exposed crystal facets, loaded content, and particle size of the deposited Au NPs. Importantly, in situ photodeposition under an ethanol solution facilitates the exposure of the highly active (111) and (220) crystal facets of Au. The introduction of Au NPs significantly enhances photocatalytic hydrogen evolution, achieving rates of 4.93, 57.88, and 15.44 μmol/h for H-KCNO/Au-(water, ethanol, and lactic acid), respectively. The observed photocatalytic activity for hydrogen evolution indicates that the exposure of the highly active planes emerges as critical for significant performance enhancement. Photoelectrochemical and photoluminescence measurements suggest that the highly active (111) and (220) crystal facets effectively segregate sites for redox reactions, thereby impeding the recombination of photogenerated electron-hole pairs.

Boosting the Proton Intercalation via Crystal Plane Optimization of TiS2 for Cycling‐Stable Aqueous Zn‐Ion Batteries

AbstractTiS2 has received significant attention as a promising anode for “Rocking‐Chair”‐type aqueous Zn‐ion batteries due to the large interlayer spacing and low discharge plateau. However, the structural distortion caused by the embedding of divalent Zn2+ as well as the undesirable hydrogen evolution reaction (HER) severely affects their cycling stability. Herein, a facet‐dependent mechanism is first deeply investigated to understand charge storage behaviors of TiS2 via differential electrochemical mass spectrometry, in situ electrochemical quartz crystal microbalance, and in situ X‐ray diffraction characterizations. By regulating the exposed crystal facets of TiS2 from (001) (TS (001)) to (011) (TS(011)), HER can be effectively inhibited, and the charge storage mechanism is transformed from Zn2+ insertion/extraction dominating to H+ insertion/extraction dominating, resulting in faster charge transfer kinetics and strong structure stability during long‐term cycling. Hence, TS(011) delivers a higher reversible capacity of 212.9 mAh g−1 at 0.1 A g−1 and a strong cycling stability of 74% capacity retention over 1000 cycles, much better than that of TS (001) with a reversible capacity of 164.7 mAh g−1 at 0.1 A g−1, a capacity retention of 17% after 1000 cycles. These new findings can provide deep insight into the rational design of high‐performance intercalation‐type electrode materials for energy storage applications.

3D printed CuFe2O4 electrode with dominant facet (111) for boosting hydrogen evolution performance

The utilization of hydrogen energy is an important way to low carbon economy, and the development of active electrodes is the most critical step for efficient hydrogen evolution reaction. With the addition of KNO3 as a capping agent, the exposed crystal facet of CuFe2O4 is regulated, and the crystal facet (111) becomes dominant. Compared to CuFe2O4 (3 1 1), CuFe2O4 (111) exhibits low barrier of water dissociation and suitable *H binding strength, resulting in high intrinsic activity. Furthermore, the 3D printed electrodes show more excellent performance. At 3D printed CuFe2O4 (111) electrode, the overpotential is only 152 mV (vs. reversible hydrogen electrode) at 100 mA cm−2, and Tafel slope is as low as 33 mV dec-1. In addition, 3D printed CuFe2O4 (111) electrodes shows high stability. The superior performance of 3D printed CuFe2O4 (111) electrodes originates from high intrinsic activity and more exposed active sites. This study provides a new path for the development of efficient, stable and inexpensive monolithic catalyst electrodes for alkaline hydrogen evolution.

Fine-Tuning the Photocatalytic Activity of the Anatase {1 0 1} Facet through Dopant-Controlled Reduction of the Spontaneously Present Donor State Density.

The present study highlights the importance of the net density of charge carriers at the ground state on photocatalytic activity of the faceted particles, which can be seen as a highly underexplored problem. To investigate it in detail, we have systematically doped {1 0 1} enclosed anatase nanoparticles with Gd3+ ions to manipulate the charge carrier concentration. Furthermore, control experiments using an analogical Nb5+ doped sample were performed to discuss photocatalytic activity in the increased range of free electrons. Overall results showed significant enhancement of phenol degradation rate and coumarin hydroxylation, together with an increase of the designed Gd/Ti ratio up to 0.5 at. %. Simultaneously, the mineralization efficiency, measured as a TOC reduction, was controlled between the samples. The observed activity enhancement is connected with the controlled decrease of the donor state density within the materials, being the net effect of the spontaneously present defects and introduced dopants, witch reduce hydroxylation and the hole trapping ability of the {1 0 1} facets. This allows to fine-tune multi-/single-electron processes occurring over the prepared samples, leading to clear activity maxima for 4-nitrophenol reduction, H2O2 generation, and ·OH formation observed for different donor densities. The optimized material exceeds the activity of the TiO2 P25 for phenol degradation by 52% (377% after surface normalization), showing its suitable design for water treatment. These results present a promising approach to boost photocatalyst activity as the combined result of the exposed crystal facet and dopant-optimized density of ground-state charge carriers.

Constructing Highly Efficient ZnO Nanocatalysts with Exposed Extraordinary (110) Facet for CO2 Electroreduction.

Electrochemical reduction of CO2 to highly valuable products is a promising way to reduce CO2 emissions. The shape and facets of metal nanocatalysts are the key parameters in determining the catalytic performance. However, the exposed crystal facets of ZnO with different morphologies and which facets achieve a high performance for CO2 reduction are still controversial. Here, we systematically investigate the effect of the facet-dependent reactivity of reduction of CO2 to CO on ZnO (nanowire, nanosheet, and flower-like). The ZnO nanosheet with exposed (110) facet exhibited prominent catalytic performance with a Faradaic efficiency of CO up to 84% and a current density of -10 mA cm-2 at -1.2 V versus RHE, far outperforming the ZnO nanowire (101) and ZnO nanoflower (103). Based on detailed characterizations and kinetic analysis, the ZnO nanosheet (110) with porous architecture increased the exposure of active sites. Further studies revealed that the high CO selectivity originated from the enhancement of CO2 adsorption and activation on the ZnO (110) facet, which promoted the conversion of CO2 toward CO. This study provides a new way to tailor the activity and selectivity of metal catalysts by engineering exposed specific facets.

Gas-phase synthesis of MoO3 nanoclusters with helium-induced high energy (060) crystal facet: Enhancing oxygen adsorption for improved gas-sensing

Adsorbed oxygen species on the surface of metal oxide semiconductors (MOS) play an important role in the field of gas-sensing. However, considering the large number of possible MOS, manipulating surface oxygen species by exposing high-energy crystal facets often requires strict experimental conditions and may not be efficiently repeated for nano MOS. This poses a huge challenge to the rational design of advanced gas-sensing materials. This study explores the fabrication of MoO3 nanocluster (NC) film by cluster beam deposition. Helium (He) is co-fed with argon (Ar) into the aggregation chamber to influence the nucleation and growth of Mo NCs. This unique process facilitated the exposure of the high-energy (060) crystal facet in MoO3 during the aging phase. This exposed crystal facet greatly reduces the oxygen adsorption energy barrier and increases the adsorbed oxygen content, resulting in a significant improvement in gas-sensing performance. The study examined the impact of energetic facets on gas sensor sensitivity by using ethanol, ammonia, and toluene as target gases. The results indicate that exposing high-energy crystal facets significantly enhances sensor performance. This approach to creating NCs with high-energy crystal facets has broad potential for advancing MOS nanostructure-based gas sensors.

Dependence of lactose adsorption on the exposed crystal facets of metals: a comparative study of gold, silver and copper.

In this theoretical work, we investigated the adsorption of a lactose molecule on metal-based surfaces, with a focus on the influence of the nature of the metal and of the type of exposed crystal facet on the adsorbed structures and energetics. More precisely, we considered three flat crystallographic facets of three face-centered cubic metals (gold, silver, and copper). For the global exploration of the energy landscape, we employed a multi-stage procedure where high-throughput searches, using a stochastic method that performs global optimization by iterating local searches, are followed by a refinement of the most probable adsorption conformations of the molecule at the ab initio level. We predicted the optimal conformation of lactose on each of the nine metal-surface combinations, classified the many low-energy minima into possible adsorption modes, and analyzed the structural, electronic and energetic aspects of the lactose molecule on the surface, as well as their dependence on the type of metal and exposed crystal facet. We observed structural similarities between the various minimum-energy conformations of lactose in vacuum and on the surface, a rough correlation between adsorption and interaction energies of the molecule, and a small charge transfer between molecule and surface whose direction is metal-dependent. During adsorption, an electronic reorganization occurs at the metal-molecule interface only, without affecting the vacuum-pointing atoms of the lactose molecule. For all types of surfaces, lactose exhibits the weakest adsorption on silver substrates, while for each coinage metal the adsorption is strongest on the (110) crystal facet. This study demonstrates that the control of exposed facets can allow to modulate the interaction between metals and small saccharides.

Cu nanosheets with exposed (111) crystal facets for highly efficient electrocatalytic CO2 reduction reaction toward methanol production

The exposed crystal facets of Cu have profound effect on its electrocatalytic CO2 reduction reaction (CO2RR) activity and product selectivity. On the other hand, at present, most of studies on...

Promoting the NH3-SCR performance of Fe2O3-TiO2 catalyst through regulation of the exposed crystal facets of Fe2O3

Iron oxide (Fe2O3)-based catalysts have garnered significant attention in the field of selective catalytic reduction with NH3 (NH3-SCR) due to their high thermal stability, N2 selectivity, low cost, and environmental friendliness. In this study, Fe2O3 catalysts with exposed {012}, {014}, and {113} facets were successfully synthesized using a hydrothermal method. Subsequently, TiO2 was loaded to construct Fe2O3-TiO2 catalysts with different crystal facets of Fe2O3. The results demonstrated that TiO2 was uniformly distributed on three different morphologies of Fe2O3. Among the catalysts, the Fe2O3{113}-TiO2 exhibited superior NOx removal capacity and a broader temperature operating range than Fe2O3{012}-TiO2 and Fe2O3{014}-TiO2. The promotion mechanism of NH3-SCR performance was determined by regulating the crystal facets of Fe2O3 in Fe2O3-TiO2 catalysts. The mechanism can be attributed to the improved redox properties, as well as the presence of additional active oxygens, surface acid sites, and adsorbed nitrate species on the Fe2O3{113}-TiO2 catalyst. In situ DRIFTS results indicated that the SCR reactions of Fe2O3-TiO2 catalysts with different crystal facets of Fe2O3 followed both the Langmuir-Hinshelwood and Eley-Rideal mechanisms. Furthermore, the Fe2O3{113}-TiO2 catalyst exhibited the improved reaction efficiency at both the Langmuir-Hinshelwood and Eley-Rideal pathways. This study provides novel insights on the influence of crystal planes on Fe2O3, which is important for optimizing Fe2O3-based NH3-SCR catalysts.

Efficient Hg0 catalytic removal by direct S-scheme heterostructure of two-dimensional Bi2MoO6 (2 0 0)/g-C3N4 nanosheets under visible light

The gaseous elemental mercury (Hg0) emitted from coal-fired flue gas is extremely harmful to the atmospheric environment and human health. In this study, a 2D/2D Bi2MoO6(2 0 0)/g-C3N4 heterojunction photocatalyst was synthesized and exhibited a high visible-light driven Hg0 removal efficiency up to 99.5% in an atmosphere consisting of N2, O2 (6%), CO2 (12%), NO (100 ppm), SO2 (800 ppm), and H2O (5%). The introduction of surfactant CTAB led to further exposure of the highly active (2 0 0) crystal facet of Bi2MoO6, with a higher reactive oxygen species ratio than the original mainly exposed (1 3 1) crystal facet, and inhibited the agglomeration of Bi2MoO6, thereby greatly reducing the micro-thickness and improving the specific surface area. The smaller thickness effectively promoted the separation of photoinduced carriers and the speed of transfer to the interface. Additionally, through EPR characterization and work function calculation, we observed that the change in the exposed crystal facet regulated the Fermi level of Bi2MoO6 nanosheets, altering the direction of the built-in electric field at the interface with g-C3N4. This formation of an S-scheme 2D/2D Bi2MoO6(2 0 0)/g-C3N4 heterostructure further facilitated the recombination of unintentional carriers and strengthened the separation and catalysis of effective photogenerated carriers. To a certain extent, this work provides a guidance for the research of photocatalysis to achieve efficient and sustainable mercury removal from coal-fired flue gas.

Understanding the role of dominant crystal facets on heterogeneous catalytic activity of BiOBr nanomaterials: Boosting catalytic efficiency through Fe (III)/Fe(II) incorporation

Herein, we have synthesized three different types of BiOBr nanomaterials (nanosheets, nanoplates and nanoflowers) by simply varying the pH of the solvent medium. Results suggest that the nanosheets contain predominantly (001) plane as the major exposed crystal facets. On the other hand, nanoflowers possess mainly (110) plane as the major exposed facet. However, nanoplates show both (001) & (110) crystal facets predominantly. Detailed morphological and elemental studies have been carried out to investigate the variation of positively charged oxygen vacancies depending on the nature of the predominantly exposed crystal facets. Furthermore, the relative extent of oxygen vacancies was further correlated with the overall surface area and the porosity of the as synthesized nanomaterials. Finally, all these three different types of nanomaterials with varying predominantly exposed crystal facets have been utilized for the catalytic reduction of para-nitrophenol to para-aminophenol as a model system through mild reducing agent NaBH4. A probable mechanism has been proposed to explain the facet dependent catalytic activities of different BiOBr nanomaterials. Finally, Fe (III)/ Fe (II) ions were specifically incorporated in BiOBr nanomaterials. The incorporation of Fe (III)/Fe (II) ions has been further correlated with the detail structural, elemental and optoelectronic properties. Depending on the exposed crystal facets, a huge enhancement has been observed for overall catalytic efficiency upon incorporation of Fe (III)/ Fe (II) ions. A suitable mechanism has been proposed.

Polyhedral zeolitic imidazolate frameworks three-dimensional photonic crystals for highly sensitive chlorinated vapors sensing

Chlorinated vapors, as one of the poisonous volatile organic compounds (VOCs), seriously pollute the environment and threaten human health. It still remains a major challenge for designing reliable chlorinated vapors sensing materials with high sensitivity. Herein, we propose a simple yet powerful optical sensor based on zeolitic imidazolate frameworks ZIF-8 three-dimensional photonic crystals (3D PCs), which keeps high efficiency in vapor sensing through varying their effective refractive index (RI). ZIF-8 3D PCs sensors with tunable crystal facets and photonic bandgap were prepared by self-assembly of monodisperse polyhedral ZIF-8 particles, which are truncated rhombic dodecahedral (TRD)-, rhombic dodecahedral (RD)-, truncated cubic (TC)-, and spherical (Sphere) ZIF-8 3D PCs sensors. The application of polyhedral ZIF-8 3D PCs sensors for chlorinated vapors detection was investigated. The selectivity was found to be closely related to the exposed crystal facets, and the TRD ZIF-8 3D PCs sensor exhibited excellent selectivity, sensitivity (0.514 nm ppm−1), and sensing performance for chlorobenzene (C6H5Cl) vapor, the ultrafast response time (≤1 s) and remarkable long-term stability and recyclability, which might ultimately benefit for practical VOCs sensing applications.

Understanding structure-performance relationships of CoOx/CeO2 catalysts for NO catalytic oxidation: Facet tailoring and bimetallic interface designing

Crystalline structure and bimetallic interaction of metal oxides are essential factors to determine the catalytic activity. Herein, three different CoOx/CeO2 catalysts, employing CeO2 nanorods (predominately exposed {110 facet), CeO2 nanopolyhedra ({111} facet) and CeO2 nanocubes ({100} facet) as the supports, are successfully prepared for investigating the effect of exposed crystal facets and bimetallic interface interaction on NO oxidation. In comparison with the {111} and {100} facets, the exposed crystal facet {110} exists the best superiority to anchor and stabilize Co species. Moreover, ultra-small CoOx clusters composed of strong Co-O coordination shells with minor Co-O-Ce interaction are formed and uniformly dispersed on the CeO2 nanorods. Structural characterizations reveal that the active exposed crystal facet {110} and the strong bimetallic interface interaction in CoOx/CeO2-nanorods (R-CC) result in more structural defect, endowing it with abundant oxygen vacancies, excellent reducibility and strong adsorption capacity. The DRIFTs spectra further indicate that the exposed crystal facet {110} has a significant promoting effect on the strength of nitrates compared with {111} and {100} facets. The bimetallic interface interaction not only significantly facilitates the formation of nitrate species at lower temperature, but also effectively suppresses the generation of sulfate and lower the sulphation rate. Therefore, R-CC catalyst exhibits the maximum NO oxidation activity with the conversion of 86.4 % at 300 °C and still sustains its high activity under cyclic condition or 50 ppm SO2. The provided crystalline structure and interaction-enhanced strategy sheds light on the design of high-activity NO oxidation catalysts.