Spherical Aberration-corrected Transmission Electron Research Articles

Enhanced catalytic oxidation of benzene though the synergistic Pt-Ni bimetallic single-atom catalyst

Excellent catalysts for the catalytic oxidation of benzene (C6H6) require active sites with robust oxidation capabilities. Heteronuclear dual-single atom catalysts can exhibit enhanced catalytic activity through synergistic interactions between the dual single atoms (SAs). Herein, we successfully engineered a bimetallic single-atom catalyst, Pt1-Ni1/TiO2-NW, which demonstrates exceptional performance in C6H6 oxidation. Various technologies, including X-ray absorption fine structure and Z-type spherical aberration-corrected transmission electron microscopy, were used to identify the bimetallic single atoms within the catalyst. The catalytic oxidation of C6H6 by Pt1-Ni1/TiO2-NW was comprehensively investigated. Finally, in-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and density functional theory (DFT) were employed to reveal the underlying mechanism for the synergetic effect of the bimetallic single atoms. The results indicate that the introduction of Ni SA favors the formation of Pt SA. The T90% of Pt1-Ni1/TiO2-NW reached 185 °C, a remarkable 40 °C lower than that of the single-atom catalyst Pt1/TiO2-NW. More importantly, the active center of Pt-O-Ni, formed by the collaboration of Pt SA and Ni SA with bridging oxygen, plays a crucial role in reducing the energy barrier during the conversion of C6H6 to phenol and further to benzoquinones. This research provides a valuable methodology for constructing heteronuclear bimetallic single-atom catalysts tailed specifically for C6H6 oxidation.

Cu@Co with Dilatation Strain for High-Performance Electrocatalytic Reduction of Low-Concentration Nitric Oxide.

Electrocatalytic reduction of nitric oxide (NO) to ammonia (NH3 ) is a clean and sustainable strategy to simultaneously remove NO and synthesize NH3 . However, the conversion of low concentration NO to NH3 is still a huge challenge. In this work, the dilatation strain between Cu and Co interface over Cu@Co catalyst is built up and investigated for electroreduction of low concentration NO (volume ratio of 1%) to NH3 . The catalyst shows a high NH3 yield of 627.20µg h-1 cm-2 and a Faradaic efficiency of 76.54%. Through the combination of spherical aberration-corrected transmission electron microscopy and geometric phase analyses, it shows that Co atoms occupy Cu lattice sites to form dilatation strain in the xy direction within Co region. Further density functional theory calculations and NO temperature-programmed desorption (NO-TPD) results show that the surface dilatation strain on Cu@Co is helpful to enhance the NO adsorption and reduce energy barrier of the rate-determining step (*NO to *NOH), thereby accelerating the catalytic reaction. To simultaneously realize NO exhaust gas removal, NH3 green synthesis, and electricity output, a Zn-NO battery with Cu@Co cathode is assembled with a power density of 3.08mW cm-2 and an NH3 yield of 273.37µg h-1 cm-2 .

Microstructure evolution of a Cr-Cr/Mo coated Zr alloys in inert gas and steam environment at high temperature

The Cr/Mo multilayer coating was applied as a diffusion barrier for Cr-coated Zr alloys. The barrier effect and eutectic resistance of the Cr/Mo multilayer were evaluated by annealing the samples up to 1400 °C in an inert gas and steam environment. The microstructure at the interface between the Cr/Mo multilayer and Zr substrate was analyzed by spherical aberration corrected transmission electron microscope (AC-TEM). After high temperature annealing, an interlayer composed of Cr-Mo-Zr mixed phases formed between the coating and Zr substrate. The atomic-resolution EDS revealed that the proportion of Cr, Mo, and Zr in the interlayer was 4:2:3. The growth of the Cr-Mo-Zr interlayer obeyed a parabolic law. The consumption rate of the outer Cr coating was compared to that of Cr coated Zr alloy samples without a Cr/Mo barrier layer. Results show that the Cr/Mo interlayer successfully reduced the Cr-Zr inter-diffusion and eutectic reaction.

Atomic insight into the BEOL thermal budget on phase transition of phase change memory cells

Research works on phase change random access memory (PCRAM) based on Ge–Sb–Te (GST) phase change materials have achieved exciting progress, but the industrialization of PCRAM still faces big challenges, including unsatisfied endurance property or unexpected cell structure failure during fabrication. Here, we investigate the impact of the thermal budget in back-end-of-line (BEOL) process on the microstructure evolution of carbon doped GST (CGST) cells. We demonstrate that the as-deposited amorphous CGST in the confined memory cell will transform to face centered-cubic (FCC) phase with uniform grain size during high temperature up to 400 °C in the BEOL process. However, if there is much more unexpected thermal budget during the BEOL process, the FCC-CGST grains will further grow and transform to highly ⟨0001⟩ oriented single crystalline hexagonal (HEX) GST, together with the formation of voids, leading to the structure failure of the storage cells. By virtue of the advanced spherical aberration corrected transmission electron microscopy (Cs-TEM), we find that there are randomly stacked seven-layered and nine-layered atomic arrangements in single crystalline HEX-GST, corresponding to the chemical stoichiometry of Ge2Sb2Te5 and Ge1Sb2Te4, respectively. Interestingly, twin crystal with the coexistence of vacancy-ordered FCC-GST and HEX-GST on the different twin boundary is observed, indicating that the twin crystals play a critical role in the coalescence and the growth of FCC-GST. This work not only sheds light on the structure failure mechanism of GST cell but also provided additional insight into the formation of HEX-phase in a confined GST memory cell.

Study on the preparation of ceramic membrane support and its Fe migration rule by high‐aluminum fly ash as raw material

AbstractIn order to reduce the cost of ceramic membrane support, ceramic membrane support was prepared using high‐aluminum fly ash as raw material, and its Fe migration rules during the preparation process are studied. The effects of sintering temperature, pore forming agent content, and binder content on the properties of support, such as porosity, pore size, bending strength and water flux have been investigated. The optimum contents of high‐aluminum fly ash, pore forming agent and binder in the ceramic membrane support are 95%, 4%, and 1% respectively, and its sintering temperature is 1300°C. The porosity, bending strength, pore size, and water flux of the prepared support are 37%, 22 MPa, 665 nm, and 2800 L/h·m2·MPa, respectively. X‐ray powder diffractometer, X‐ray fluorescence spectrometer, X‐ray photoelectron spectrometer, inductively coupled plasma spectrometer, transmission electron microscope, spherical aberration corrected transmission electron microscopy, and laser Raman spectroscopy were used to characterize the support and Fe existing morphology in it. The results show that the main phases of sintered support are mullite, corundum, and silica. Massive mullite is produced when the sintering temperature reaches 1200°C. The content of mullite increases with increasing sintering temperature. About 7.7 % content of total Fe in the support exists in the form of Fe2O3. About 92.3% content of total Fe is dissolved into mullite. Fe is evenly distributed in mullite, and it is enriched at the grain boundary by element segregation. Fe in mullite is difficult to dissolve under strong acid conditions, so its stability is very strong.

Engineering Sub-Nanometer Hafnia-Based Ferroelectrics to Break the Scaling Relation for High-Efficiency Piezocatalytic Water Splitting.

Reversible control of ferroelectric polarization is essential to overcome the heterocatalytic kinetic limitation. This can be achieved by creating a surface with switchable electron density; however, owing to the rigidity of traditional ferroelectric oxides, achieving polarization reversal in piezocatalytic processes remains challenging. Herein, sub-nanometer-sized Hf0.5 Zr0.5 O2 (HZO) nanowires with a polymer-like flexibility are synthesized. Oxygen K-edge X-ray absorption spectroscopy and negative spherical aberration-corrected transmission electron microscopy reveal an orthorhombic (Pca21 ) ferroelectric phase of the HZO sub-nanometer wires (SNWs). The ferroelectric polarization of the flexible HZO SNWs can be easily switched by slight external vibration, resulting in dynamic modulation of the binding energy of adsorbates and thus breaking the "scaling relationship" during piezocatalysis. Consequently, the as-synthesized ultrathin HZO nanowires display superb water-splitting activity, with H2 production rate of 25687µmolg-1 h-1 under 40kHz ultrasonic vibration, which is 235and 41times higher than those of non-ferroelectric hafnium oxides and rigid BaTiO3 nanoparticles, respectively. More strikingly, the hydrogen production rates can reach 5.2µmolg-1 h-1 by addition of stirring exclusively.

Triethylenediamine cobalt complex encapsulated in a metal–organic framework cage to prepare a cobalt single-atom catalyst with a high Co-N4 density for an efficient oxygen reduction reaction

Transition metal single atom catalysts (TM SACs) are the most promising oxygen reduction reaction (ORR) catalysts for proton exchange membrane fuel cells (PEMFCs) and metal-air batteries. However, the low density of M-Nx active sites seriously hinders further improvement of the ORR electrocatalytic activity. Here, a strategy for encapsulating nitrogen-rich guest molecules (triethylenediamine cobalt complex, [Co(en)3]3+) was proposed to construct a high-performance cobalt single-atom catalyst (Co-encapsulated SAC/NC). With this strategy, the guest molecules are encapsulated into metal–organic framework (MOF) cages as an additional cobalt source to boost cobalt loading, while abundant nitrogen from guest molecules contributes to the formation of Co-N4 active sites. Remarkably, the resulting Co-encapsulated SAC/NC has a high cobalt loading amount of 4.03 wt%, and spherical aberration-corrected transmission electron microscopy (AC-TEM) has confirmed that most cobalt exists in a single-atom state. As a result, the Co-encapsulated SAC/NC exhibits excellent ORR catalytic performance with a half-wave potential of 0.88 V. Furthermore, Zn-air batteries employing Co-encapsulated SAC/NC as air cathode show high peak power density and excellent cycling stability. Density functional theory (DFT) calculations reveal that adjacent active sites have different rate-determining steps and lower reaction energy barriers than a single active site.

In situ observation of two-step crystallization of amorphous oxides via electron microscopy

The transformation from amorphous materials to crystals and the corresponding microscopic mechanism have become a research focus in materials science, condensed matter physics, and biophysics etc. In this paper, taking Y3Al5O12 (YAG) as an example, the crystallization process of amorphous YAG oxide is investigated from an atomic point of view through the combination of spherical aberration-corrected transmission electron microscopy (SCTEM) with an in situ heating method, and the morphology and structural evolution of the surface and interface are explored. It is observed that the crystallization proceeds on the surface and interior of the amorphous YAG separately. Through atomic-scale imaging, it is determined that semi-ordered structures are formed in a few atomic layers at the amorphous/crystalline interface and that the structural transformation process from the amorphous to the semi-ordered state and then to the crystal structure may be the main reason for the multiple stages of the crystallization of amorphous oxides. This study demonstrates the mechanism of the amorphous-to-crystal transformation on the atomic scale and contributes to gaining a better understanding of the crystallization process of bulk oxides, especially complex metal oxides.

Direct atomic-scale visualization of the 90° domain walls and their migrations in Hf0.5Zr0.5O2 ferroelectric thin films

Domain walls (DWs) play an essential role in altering the polarization and related properties of ferroelectric materials, and are regulated by the mechanism of changing atomic configuration. However, compared with perovskite ferroelectrics, the DWs in hafnia-based fluorite-structure ferroelectric is experimentally lacking, especially with regard to detailed studies of atomic-scale structures. The present work used spherical aberration-corrected transmission electron microscope combined with in-situ technique to ascertain the origin, atomic arrangements of 90° DWs in Hf0.5Zr0.5O2 thin films. Different types of 90° DWs were found to exhibit varying migration behaviors in response to the concentration of oxygen vacancies. Point defects and corresponding changes in the local strain field are proposed to drive DW switching in this material. These new insights into the atomic-scale characteristics of 90° DWs are expected to assist in elucidating the structure of DWs and improve our understanding of the ferroelectric characteristics of new type hafnia-based materials.

Interaction mechanism between immiscible Fe-Mg element diffusion and crystal defect annihilation in the steel/Mg composite interface region

Crystal defect-induced elemental diffusion between immiscible metals is the key to achieve metallurgical bonding. However, the interaction between immiscible element diffusion and crystal defect annihilation is unclear. In this paper, in-situ heat treatment experiments were conducted at the steel/Mg composite interface by ambient atmosphere spherical aberration corrected transmission electron microscope. The immiscible element diffusion phenomenon and crystal defect annihilation phenomenon in the composite interface region were studied, and the interaction mechanism was revealed. The results show that during the heat treatment, the diffusion of Mg element to the steel side is obvious, while the diffusion of Fe element to the Mg side is not obvious, which is called “one-way selective diffusion effect”. The annihilation rate of steel crystal defects is much smaller than that of Mg. The stable crystal defects of steel in the interface region can provide a channel for Mg elements diffusion, while the faster annihilation rate of Mg crystal defects causes Fe elements to hardly diffuse into Mg. The Mg elements that have diffused into the steel side have a pinning effect on dislocations and grain boundary movement, which in turn increases the thermal stability of the steel crystal defects. This study provides theoretical guidance for promoting the element diffusion at the immiscible metals composite interface.

Guanosine-derived atomically dispersed Cu-N3-C sites for efficient electroreduction of carbon dioxide

Single-atom copper (Cu) embedded within carbon catalysts have demonstrated significant potential in the electrochemical reduction of carbon dioxide (CO2) into valuable chemicals and fuels. Herein, we develop a straightforward and template-free strategy for synthesizing atomically dispersed CuNC catalysts (CuG) by annealing the self-assembled guanosine. The CuG catalysts display two-dimensional morphology, tunable pore size and large surface areas that can be adjusted by changing carbonization temperature. Spherical aberration-corrected transmission electron microscopy reveals that single-atom Cu are homogeneously dispersed on the surface of carbon nanosheets. The optimum CuG-1000 catalysts achieve a high CO Faradaic efficiency (FEco) up to 99% and a high CO current density of 6.53 mA cm−2 (−0.65 V vs. RHE). Besides, the flow cell test of CuG-1000 shows a high current density up to 25.2 mA cm−2 and the FEco still exceeded 91% after more than 20 h of testing. Specifically, the existence of Cu-N3-C active sites was proved by extended X-ray absorption fine structure (EXAFS). Density functional theory evidences that tricoordinated copper with N can largely regulate the adsorption and desorption of key intermediates by transferring electrons to *COOH through Cu atoms, thereby improving selectivity toward CO. This work demonstrates the active origin of CuNC catalysts in CO2 electroreduction and offers a blueprint to construct atomically dispersed transition site catalysts by supramolecular self-assembly strategy.

Recognizing the formation of single-atom vanadium by enthalpy and its advantage in selective catalytic reduction of nitrogen oxide

Developing a more effective catalyst for the environmental pollutant is always the pursuit of worldwide researchers. In previous reports, most works were focused on prepared catalysts, and more efforts should explore process from a precursor to the formed catalyst. In this work, V supported TiO2 catalysts were synthesized with different V loadings, and compared in selective catalytic reduction of nitrogen oxide. For the first time, differential scanning calorimetry was used to analyze the forming enthalpy for these catalysts. As a result, turnover frequency (TOF) was decreased from 0.05 to 0.001 s−1 when the loading was increased from 0.05 to 15 mol%. At the same time, the forming enthalpy was decreased from 16.53 to 1.80 KJ·mol−1. Spherical Aberration Corrected Transmission Electron Microscope recognized both single-atom and cluster V even at the lowest loading. What’s more, density functional theory revealed that single-atom V had a lower dehydrogenation energy (1.088–1.152 eV) than cluster V during the catalysis (1.834–1.850 eV). According to these evidences, single-atom V had bigger formation enthalpy, lower dehydrogenation energy, and larger TOF than cluster V. These results help to optimize the preparation process for an effective catalyst, which is in favor of hazardous-pollutant treatment.

Origin of the bias instability in CsPbI3 light-emitting diodes

With the rapid development of all-inorganic CsPbX3 (X = I, Br, and Cl) perovskite light-emitting diodes (PeLEDs), their external quantum efficiency (EQE) has made great progress in the last few years. However, severe performance degradation at the operation condition impedes its large-scale industrial application. In this text, by using the advanced spherical aberration corrected transmission electron microscope (TEM), the degradation pathway of PeLEDs under bias loading was more systematically and comprehensively, especially from the viewpoint of its microstructural evolution pathway, which showed that iodine vacancy migration triggered the structural collapse was the primary inducement of performance decay. To solve this problem, inorganic termination ZnI2 was employed to passivate the surface halide vacancy defects and supplement the halide ion into the lattice, which significantly improves the photoluminescence (PL) lifetime and stability of CsPbI3 quantum dots (QDs). As expected, not only the EQE of PeLEDs has been greatly improved, but also the operating half-lifetime is enhanced by about 4 times as compared with the original one. Microstructural characterization and density functional (DFT) calculations confirm that the preferential segregation of Zn element on the surface of QDs was the principal cause to passivate the defect state of QDs, which exhibits lower formation energy and better operational stability.

Unveiling positive impacts of fluorine anion doping on extraordinary catalytic activity of bifunctional-layered double perovskite electrodes for solid oxide fuel cells and electrolysis cells

To address the impacts of anion doping, F-doped layered double perovskites (Pr1.1Ba0.9Co2O5+δFx) have been synthesized, demonstrating bifunctional activity in both solid oxide fuel cell and solid oxide electrolysis cell models. The F doping induces increased oxygen vacancy concentration and enhanced electrical conductivity. Combined with spherical aberration-corrected transmission electron microscopy and X-ray photoelectron spectroscopy analyses, the F− anions are successfully introduced into the host lattice, promoting the oxygen surface exchange/diffusion rates. From the density functional theory calculations, the covalence between Co 3d and O 2p-orbital is enlarged in the F-doped model, and both oxygen reduction reaction and oxygen evolution reaction activities are improved. The area-specific resistance of the Pr1.1Ba0.9Co2O5+δF0.1 (P1.1BCOF0.1) electrode is as low as 0.033 Ω/cm2 at 700 °C. The P1.1BCOF0.1 cathode-based fuel cell delivers a peak power density of 1102 mW/cm2, along with an excellent operating stability at 700 °C. Moreover, the current density of 1335 mA/cm2 is achieved in the P1.1BCOF0.1 anode-based electrolysis cell at 1.8 V toward CO2 reduction reaction at 750 °C. These results here highlight the performance origin and bifunctional activity of fluorine-doped perovskite materials, which may help us rationally design the oxide catalysts.

Achieving superior cryogenic impact toughness and sufficient tensile properties in a novel high-Mn austenitic steel weld metal via cerium addition

The microstructure and mechanical properties of the novel cryogenic high-Mn austenitic steel weld metals with different cerium (Ce) contents were investigated via electron back-scattered diffraction, scanning and spherical aberration-corrected transmission electron microscopy, and cryogenic impact and tensile test. The results indicated that the crystallographic grain size was significantly refined, and the relative frequency of high-angle grain boundaries increased with the increase of Ce content. Ce element addition could modify the main inclusions from irregular Al2O3 into regular Ce-containing inclusions. Meanwhile, the inclusions gradually became fine and dispersed, and the volume fraction of inclusions decreased with the increase of Ce content from 0 to 870 ppm. The increase of Ce content continuously improved cryogenic impact toughness from 82 J to 116 J, and yield strength, tensile strength and total elongation all increased to different degrees. We found that in addition to the beneficial changes in inclusion modification, grain refinement and increase in the proportion of high-angle grain boundaries, the solid solution of Ce also played a crucial role in the mechanical properties.

Preparation and characterization of polyethylene-based activated carbon fibers stabilized at low temperatures

This study introduces a method for preparing low-temperature-stabilized high-density polyethylene (HDPE)-based activated carbon fibers (HDPE-ACFs) by using a hybrid crosslinking method involving electron beam irradiation and sulfuric acid crosslinking. The HDPE fibers were primary crosslinked with an electron beam at radiation doses of 1000–2000 kGy before being secondarily crosslinked in sulfuric acid at 100 °C for 30–120 min. The hybrid crosslinked fibers were carbonized at 700 °C for 1 h and then formed into activated carbon fibers upon steam activation at 900 °C for 40–70 min. The surface morphology and structural characteristics of the HDPE-ACFs were observed via field-emission scanning electron microscopy, spherical aberration-corrected field-emission transmission electron microscopy, and X-ray diffraction analysis. The pore characteristics were analyzed by using Brunauer–Emmett–Teller and Barrett–Joyner–Halenda equations. As the activation time increased, the specific surface area and total pore volume increased by up to 2090 m2/g and 1.30 cm3/g, respectively. Thus, activated carbon fibers with a high tensile strength value of up to 78 MPa and specific surface area of at least 2000 m2/g were successfully prepared.

Probing into the conduction band and type of carriers/traps on red/orange persistent phosphors in vacancy & solid-solution induced (Sr/Ba)1-xCaxGe4-yO9:Mn2.

Long-wavelength afterglow has been a key issue in the investigation of afterglow materials. Herein, the orange/red (Sr/Ba)1-xCaxGe4-yO9:0.01Mn2+ is prepared by the introduction of vacancy induction and solid solution. The (Sr/Ba)Ge4O9:Mn2+ hardly possesses an afterglow phenomenon and exhibits only red/orange photo-luminescence (PL) attributed to the d-d transition of Mn2+, while samples with reduction of the Ge4+ content and with replacement by Ca2+ show bright afterglow emission with the peak located at about 612 nm/620 nm. The emerging broadband peak comes from charge transfer involving Mn2+ and nearby defect clusters and the bottom of the conduction band (CB). The introduction of V''''Ge creates a defective energy level above the valence band, but the ground state energy difference with Mn2+ is too large (>1 eV) to allow hole transfer, which was confirmed by ultraviolet photoelectron spectroscopy (UPS), spherical aberration-corrected transmission electron microscopy (AC-STEM), charge differential density (CDD) analysis, electron paramagnetic resonance (EPR) analysis, etc. With this achievement, we propose an original design strategy for long-wavelength afterglow and a more reasonable afterglow mechanism, which is of great importance for the investigation of long-wavelength afterglow materials.

Highly efficient electrooxidation of ethanol on CuPtPd trimetallic catalyst

Pt-based ternary metal catalysts have excellent catalytic performance and high stability for ethanol oxidation (EOR). In this paper, Cu-Pt-Pd ternary alloy catalysts are prepared by a facile electrochemical deposition method. The morphology and elemental composition are probed by spherical aberration corrected transmission electron microscope (ACTEM) and X-ray photoelectron spectroscopy (XPS). Many hollow nanosphere are uniformly distributed on the surface of Cu-Pt-Pd catalysts. In various Cu-Pt-Pd catalysts, the peak current density and the mass activity of Cu-Pt1Pd3.2 are 166.7 mA⋅cm−2 and 2436 mA⋅mgPt+Pd-1 for EOR, which are 13.4 times and 8.1 times as those of commercial Pt/C catalysts. The Cu-Pt1Pd3.2 also exhibits excellent CO toxicity resistance. The strong interaction and synergistic effect among Cu, Pt and Pd would enhance its electro-catalytic activity. The above research results will be potential useful value in expanding application fields of Pt-based ternary metal catalysts for EOR.

Interfacial dynamics of GaP/Si(100) heterostructure grown by molecular beam epitaxy

The atomic structure and surface chemistry of GaP/Si(100) heterostructure with different pre-layers grown by molecular beam epitaxy are studied. It is found that GaP epilayer with Ga-riched pre-layers on Si(100) substrate has regular surface morphology and stoichiometric abrupt heterointerfaces from atomic force microscopes (AFMs) and spherical aberration-corrected transmission electron microscopes (ACTEMs). The interfacial dynamics of GaP/Si(100) heterostructure is investigated by X-ray photoelectron spectroscopy (XPS) equipped with an Ar gas cluster ion beam, indicating that Ga pre-layers can lower the interface formation energy and the bond that is formed is more stable. These results suggest that Ga-riched pre-layers are more conducive to the GaP nucleation as well as the epitaxial growth of GaP material on Si(100) substrate.

Pt–Ru bimetallic nanoparticles anchored on carbon nanotubes/polyaniline composites with coral-like structure for enhanced methanol oxidation

In order to surmount the poor stability and low utilization efficiency of Pt catalysts, the Pt-Ru bimetallic nanoparticles/polyaniline/multi-walled carbon nanotube composites (PRPM) were fabricated. Structural characterization data by transmission electron microscope, scanning electron microscope, spherical aberration corrected transmission electron microscope, X-ray photoelectron spectroscopy analysis revealed PRPM with coral-like structure. The particle size of Pt-Ru bimetallic nanoparticles were about 3.76 nm. It exhibited higher mass activity of Pt 10 Ru 1 /PANI/CNTs catalyst (987.9 mA·mgPt −1 ) compared to Pt 10 Ru 1 /CNTs catalyst (619.2 mA·mgPt −1 ) for MOR. The Pt 10 Ru 1 /PANI/CNTs catalyst showed lower onset potentials, lower peak current potential compared to Pt-Ru/C in CO stripping experiment. The calculated results were confirmed by the above experimental data. This work provided scientific guidance for fabricating new functional materials in fuel cells field. • The Pt-Ru/polyaniline/carbon nanotubes composites have coral-like structure. • The Pt 10 Ru 1 /PANI/CNTs catalysts had the lower potential and higher current density for MOR. • The prepared composites showed higher performance in methanol and CO oxidation. • The prepared bimetallic catalysts are potential candidate for MOR.