Synthesis of highly dispersed and active palladium/carbon nanofiber catalyst for formic acid electrooxidation

Highly dispersed and active palladium/carbon nanofiber (Pd/CNF) catalyst is synthesized by NaBH₄ reduction with trisodium citrate as the stabilizing agent. The obtained Pd/CNF catalyst is characterized by high resolution transmission electron microscopy (HRTEM) and X-ray diffraction (XRD). The results show that the Pd nanoparticles with an average particle size of ca. 3.8 nm are highly dispersed on the CNF support even with a small ratio of citrate to Pd precursor, which is believed to be due to the pH adjustment of citrate stabilized colloidal Pd nanoparticles. The cyclic voltammetry and chronoamperometry techniques show that the obtained Pd/CNF catalyst exhibits good catalytic activity and stability for the electrooxidation of formic acid.     

Pd5Cu4Pt oxygen reduction nanocatalyst for PEM fuel cells

Carbon dispersed Pd₅Cu₄Pt nanocatalyst synthesized by chemical reduction with NaBH₄ for the oxygen reduction reaction (ORR) in acid media is investigated. Nanocatalyst is physically characterized by transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (DRX). Results demonstrate the formation of conglomerate nanometric particles ranging from 2 to 10 nm in size. Electrochemical activity is demonstrated by cyclic voltammetry (CV) and rotating disk electrode (RDE) techniques. The results show that the onset potential for the ORR on Pd₅Cu₄Pt is shifted by ca. 50 mV to more positive values and enhanced catalytic current densities are observed in comparison to carbon dispersed PdCu and Pd catalysts. The Pd₅Cu₄Pt tested as cathode electrode in a membrane-electrode assembly (MEA) shows a power density of 330 mW cm⁻² at 0.5 V and 80 °C, resulting an attractive low Pt content cathode nanocatalyst for PEM fuel cells.     

Pd nanoparticles supported on PDDA-functionalized carbon black with enhanced ORR activity in alkaline medium

Pd/C catalyst with small particle size, high dispersion and high wt.% of metal was in situ synthesized by a simple aqueous phase reduction method. Poly(diallyldimethylammonium chloride) PDDA-functionalized carbon black was used as a support material for the in situ deposition of Pd nanoparticles by means of electrostatic attraction. The catalysts were characterized by transmission electron microscopy, X-ray diffractometry and X-ray photoelectron spectroscopy, cyclic voltammetry and rotating disc electrode test. The results indicated that Pd nanoparticles with an average size of 2.09 nm were uniformly dispersed onto the carbon black with a metal weight percentage of ∼30 wt.%. The prepared Pd/C catalyst has showed remarkably larger electrochemical surface area and higher and more stable ORR activity as compared to commercial Pd/C catalyst and commercial Pt/C catalyst in alkaline media, which was believed to be a promising alternative to Pt-based catalyst used in alkaline fuel cell.     

Carbon nanotube-copper oxide-supported palladium anode catalysts for electrocatalytic enhancement in formic acid oxidation

Pd/xCuO–10CNT (x = 1, 2, 3, 4) catalysts were synthesized using an improved polyol method. Uniformly prepared catalyst structures and chemical compositions of the catalysts delivered a high oxidation performance. The prepared catalysts were characterized via transmission electron microscopy (TEM), X-ray powder diffraction (XRD), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). The formation of homogenous active Pd metal and CuO nanoparticle-modified CNT surfaces was found. Meanwhile, the electrocatalytic activity and the long-term stability performance of the prepared catalysts toward formic acid oxidation reaction (FAOR) were also employed via cyclic voltammogram (CV) and chronoamperometry (CA), respectively. Prominently, the prepared Pd/xCuO–CNT nanocomposite catalyst presented an outstanding electrocatalytic performance with a higher maximum forward peak current density (26.9 mA cm^?2) than those of catalysts Pd/CNT (3.4 mA cm^?2) and Pd/C (2.3 mA cm^?2) toward FAOR in the H₂SO₄ electrolyte, representing high conductivity CNT, and dispersed Pd nanoparticles with a large active surface area, on the CuO-CNT support. Additionally, the prepared catalysts also had outstanding stability and an excellent CO poisoning tolerance through the modified Pd structures on CuO-supported CNT. The insertion of CuO onto the CNT surface before Pd loading provided additional electrochemical active sites due to the enhanced geometric and bifunctional system. CuO supports the adsorption of oxygen-containing species (OH_ads) on the catalyst surface, and the electron effect among Pd and Cu metals is beneficial for charge transfer.     

Highly active carbon nanotube supported PdAu alloy catalysts for ethanol electrooxidation in alkaline environment

At present, ethanol electrooxidation study is performed on CNT supported Pd and PdAu catalysts to investigate the effect of Au addition to Pd towards the ethanol electrooxidation activity. NaBH₄ reduction method is employed for the synthesis of Pd/CNT, Pd₉₀Au₁₀/CNT, Pd₉₀Au₁₀/CNT, Pd₇₀Au₃₀/CNT, Pd₅₀Au₅₀/CNT, and Pd₄₀Au₆₀/CNT catalysts. These catalysts are characterized via advanced surface analytical techniques namely N₂ adsortion-desoprtion measurements,X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM). The characterization results revealed that Pd₉₀Au₁₀/CNT has 205.42 m²/g and 1.18 cm³/g BET surface area (m²/g) and pore volume (cm³/g), respectively. On the other hand, XRD and XPS results revealed that the electronic state of Pd₉₀Au₁₀/CNT catalyst changed by Au addition to Pd. TEM and HRTEM and elemental mapping results reveal that Pd and Au is homogeneously dispersed and alloying of Pd and Au is clearly observed, in agreement with the XRD and XPS results. Ethanol electrooxidation measurements in alkaline environment are performed by Cyclic Voltammetry (CV), Chronoamperometry (CA), Electrochemical impedance spectroscop (EIS) techniques. Pd₉₀Au₁₀/CNT displayed the highest specific and mass activity. The synergistic effect between Pd and Au at optimized metal ratio was utilized to obtain an improvement in specific activity. Furthermore, Pd₉₀Au₁₀/CNT showed the lowest charge transfer resistance (R_ct) and a long term stability. As a result, it is clear that PdAu catalyst is a promising catalyst for Alkaline Direct Ethanol Fuel Cells.     

An ambient aqueous synthesis for highly dispersed and active Pd/C catalyst for formic acid electro-oxidation

An experimentally simple process is reported in aqueous solution and under ambient conditions to prepare highly dispersed and active Pd/C catalyst without the use of a stabilizing agent. The [Pd(NH₃)₄]²⁺ ion is synthesized with gentle heating in aqueous ammonia solution without formation of Pd(OH)_x complex intermediates. The adsorbed [Pd(NH₃)₄]²⁺ on the surface of carbon (Vulcan XC-72) is reduced in situ to Pd nanoparticles by NaBH₄. The Pd/C catalyst obtained is characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results show that highly dispersed Pd/C catalyst with 20 wt.% Pd content and with an average Pd nanoparticle diameter of 4.3-4.7 nm could be obtained. The electrochemical measurements show that the Pd/C catalyst without stabilizer has a higher electro-oxidation activity for formic acid compared to that of a Pd/C catalyst prepared in a traditional high temperature polyol process in ethylene glycol.     

Reduced graphene oxide supported Fe2B as robust catalysts for oxygen reduction reaction

Transition metal borides have great potential to be low-cost, high-performance catalysts for novel energies despite the synthesis is rather difficult. In this paper, the reduced graphene oxide (rGO) supported iron boride (Fe₂B/rGO) based catalysts are synthesized by a facile reduction method. The successful synthesis of Fe₂B is confirmed by X-ray diffraction, scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), X-ray photo-electron spectroscopy (XPS) and other tests. HRTEM tests showed that the constructed Fe₂B was embedded in the rGO, where B played the role of coordination atoms which could regulate the electronic structure of the catalysts and improve the catalytic performance towards oxygen reduction reaction (ORR). The electrochemistry tests showed that the peak current intensity of the Fe₂B/rGO catalyzed ORR could be reached up to 7.6 mA/cm², which surpassed that of the Pt/C (20 wt%) catalyst. The current intensity can be kept at 82.47% after continuous running 20,000 s, which is higher than the Pt/C catalyst (79.4%). The onset potential reaches up to 0.95 V, which is only 0.06 V lower than that of Pt/C (20 wt%) catalyst. Both RDE and RRDE tests confirmed that the Fe₂B/rGO catalyzed ORR major happed through 4-electron pathway. The redistributed electron between iron and boron atoms promoted the happening of ORR on Fe₂B/rGO catalysts. The results of this work provide a novel way to develop high performance transition metal boride based catalysts for ORR.     

High performance Pd-based catalysts for oxidation of formic acid

Two novel catalysts for anode oxidation of formic acid, Pd₂Co/C and Pd₄Co₂Ir/C, were prepared by an organic colloid method with sodium citrate as a complexing agent. These two catalysts showed better performance towards the anodic oxidation of formic acid than Pd/C catalyst and commercial Pt/C catalyst. Compared with Pd/C catalyst, potentials of the anodic peak of formic acid at the Pd₂Co/C and Pd₄Co₂Ir/C catalyst electrodes shifted towards negative value by 140 and 50 mV, respectively, meanwhile showed higher current densities. At potential of 0.05 V (vs. SCE), the current density for Pd₄Co₂Ir/C catalyst is as high as up to 13.7 mA cm⁻², which is twice of that for Pd/C catalyst, and six times of that for commercial Pt/C catalyst. The alloy catalysts were nanostructured with a diameter of ca. 3–5 nm and well dispersed on carbon according to X-ray diffraction (XRD) and transmission electron microscopy (TEM) measurements. The composition of alloy catalysts was analyzed by energy dispersive X-ray analysis (EDX). Pd₄Co₂Ir/C catalyst showed the highest activity and best stability making it the best potential candidate for application in a direct formic acid fuel cell (DFAFC).     

Electrodeposited graphene hybridized graphitic carbon nitride anchoring ultrafine palladium nanoparticles for remarkable methanol electrooxidation

Exploiting high performance electrocatalysts is crucial for the effective electrooxidation of methanol, although some barriers exist. Herein, we develop a hybrid support composed of graphitic carbon nitride (g-C₃N₄) and reduced graphene oxide (rGO) synergistically anchoring sufficient ultrafine palladium (Pd) nanoparticles via a simple one-step electrodeposition technique. The morphology and structure were characterized by scanning/transmission electron microscopy, X-ray diffraction, Raman spectroscopy and X-ray photoelectron spectroscopy, which confirmed that the Pd nanoparticles were massively and uniformly dispersed on the support of g-C₃N₄@rGO with a the average particle size of 5.87 nm, deriving from the nitrogen in g-C₃N₄ contributing to the electron transport highway on the rGO nanosheet layer surface. Furthermore, electrochemical results suggested that the Pd/g-C₃N₄@rGO showed a high electrocatalytic efficiency for methanol oxidation with a high current density reached 0.131 mA cm⁻². Based on a novel approach to the g-C₃N₄@rGO hybrid nanostructure, this work offers a promising method for the design and synthesis for the superior performance methanol electrocatalyst.     

Pd/C nanocatalyst with high turnover frequency for hydrogen generation from the formic acid–formate mixtures

Pd/C nanocatalyst with high turnover frequency (TOF) for hydrogen generation from the formic acid (FA)–sodium formate (SF) mixtures was prepared via an ex situ reduction of PdCl₂ used formate in the presence of citric acid. The morphology and property of the Pd/C catalyst before and after decomposition of FA–SF mixture were characterised using transmission electron microscopy, high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, energy dispersive spectroscopy, X-ray diffractometer and Fourier transform infrared spectrometer. Over this Pd/C catalyst, a TOF of 228.3 h⁻¹ was observed for a FA–SF mixture with a FA/SF ratio of 1:9. The observed TOF was the highest ever reported for heterogeneous Pd/C catalysts. The deactivation of the Pd/C catalyst was attributed to desorption of citric acid, reduction of Pd^II content and adsorption of CO. Washing and drying could partially recover the activity of the Pd/C catalyst.     

Evaluation of carbon nanotubes produced from toluene steam reforming as catalyst support for selective catalytic reduction of NOx

There is current interest in developing low cost, effective catalysts for the low temperature selective catalytic reduction (SCR) of nitrogen oxides (NO_x). In this work, we have applied carbon nanotubes (CNTs), produced as a by-product of hydrogen production from the steam reforming of toluene (as a representative hydrocarbon), as a catalyst support for a V₂O₅–WO₃ catalyst for SCR of NO_x. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analysis showed well dispersed metals on the surface of the CNTs. The V₂O₅–WO₃/CNT catalyst has exhibited NO_x reduction efficiency higher than 95% at reaction temperatures between 340 and 400 °C. However, there was a low NO_x reduction at SCR reaction temperature of less than 200 °C which is suggested to be due to the lack of Lewis acid sites, as determined from NH₃-TPD (temperature program desorption) analysis. Future work to lower the SCR reaction temperature with high NO_x efficiency is suggested.     

Formic acid oxidation reaction on a PdxNiy bimetallic nanoparticle catalyst prepared by a thermal decomposition process using ionic liquids as the solvent

The nano-catalysts of Pd_xNi_y bimetallic nanoparticles (NPs, the nominal atomic ratios of Pd to Ni are 2:1, 3:2 and 1:1) supported on multi-walled carbon nanotubes (MWCNTs) (denoted as Pd_xNi_y/MWCNTs) have been synthesized by a thermal decomposition process using room temperature ionic liquids (RTILs) of N-butylpyridinium tetrafluoroborate (BPyBF₄) as the solvent. X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscopy (TEM) were employed to characterize the morphology of the samples, revealing that the prepared Pd_xNi_y NPs were quite uniformly dispersed on the surface of MWCNTs with an average particle size of ∼8.0 nm. Formic acid oxidation reaction (FAOR) was investigated on the as-prepared catalysts by using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), demonstrating that the peak current on the Pd₃Ni₂/MWCNTs catalyst was about three times higher than that on the Pd/MWCNTs. The lower electrode potential and easier hydrogen evolution, based on the results obtained from chronopotentiometry and CV, respectively, were thought as the main reasons for the excellent electrocatalysis of the Pd₃Ni₂/MWCNTs toward formic acid oxidation reaction (FAOR) when compared to other samples.     

An efficient antimony doped tin oxide and carbon nanotubes hybrid support of Pd catalyst for formic acid electrooxidation

We report on a mixture of antimony doped tin oxide (ATO) and carbon nanotubes as a novel support of Pd catalyst (Pd/ATO-CNTs) with the aims to enhance electron and proton conductivity of hybrid support, and catalytic activity and stability for formic acid electrooxidation. The surface content, morphology and structure of the as-prepared Pd/ATO-CNTs catalysts with different CNTs contents have been characterized by X-ray diffraction (XRD), energy dispersive analysis of X-ray (EDAX), inductively coupled plasma-optical emission spectroscopy (ICP-OES), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM) and high angle annular dark field STEM (HAADF-STEM), respectively. The electrocatalytic properties of the samples for formic acid electrooxidation reaction are investigated by cyclic voltammetry, chronoamperometry and electrochemical impedance spectroscopy. The results show that the activity and stability of Pd/ATO-CNTs catalyst is obviously higher than that of Pd/CNTs catalyst for formic acid electrooxidation due to unique physical and chemical properties of ATO and metal-support interaction between Pd nanoparticles and ATO. Moreover, the Pd/ATO-CNTs10 (CNTs content is 10 wt.% of ATO-CNTs support mass) with smaller Pd particle size and narrower size distribution on surface of the hybrid support exhibits the best performance for formic acid electrooxidation among all the samples.     

Synthesis of PdNi catalysts for the oxidation of ethanol in alkaline direct ethanol fuel cells

Carbon-supported PdNi catalysts for the ethanol oxidation reaction in alkaline direct ethanol fuel cells are successfully synthesized by the simultaneous reduction method using NaBH₄ as reductant. X-ray diffraction characterization confirms the formation of the face-centered cubic crystalline Pd and Ni(OH)₂ on the carbon powder for the PdNi/C catalysts. Transmission electron microscopy images show that the metal particles are well-dispersed on the carbon powder, while energy-dispersive X-ray spectrometer results indicate the uniform distribution of Ni around Pd. X-ray photoelectron spectroscopy analyses reveal the chemical states of Ni, including metallic Ni, NiO, Ni(OH)₂ and NiOOH. Cyclic voltammetry and chronopotentiometry tests demonstrate that the Pd₂Ni₃/C catalyst exhibits higher activity and stability for the ethanol oxidation reaction in an alkaline medium than does the Pd/C catalyst. Fuel cell performance tests show that the application of Pd₂Ni₃/C as the anode catalyst of an alkaline direct ethanol fuel cell with an anion-exchange membrane can yield a maximum power density of 90 mW cm⁻² at 60 °C.     

High performance PtPdAu nano-catalyst for ethanol oxidation in alkaline media for fuel cell applications

In the present investigation, Vulcan XC-72 supported Pt and Pt based binary and ternary catalysts (Pt/C, PtPd/C, PtAu/C, PtPdAu/C) have been synthesized under borohydride reduction scheme and applied for the study of the electro-oxidation of ethanol in alkaline media at room temperature. The surface morphology of the catalysts was determined by XRD (X-ray diffraction) & TEM (transmission electron microscopy) analysis. XRD patterns reveal that all the catalysts have disordered face center cubic lattice structures. Low resolution TEM images reveal uniform dispersion of metal nano particles on carbon support having an average size of 3-4.5 nm. HRTEM is also carried out for the determination of the distance between the lattice planes. Different textural properties including external surface area, pore volume and widths of the catalyst matrix were calculated by applying the BET equation to the adsorption isotherms. During electrolysis substantial increase in anodic peak current was observed for ethanol oxidations when the second and third metal component was introduced into the Pt matrix as in case of PtPdAu/C catalysts. The charge transfer resistance (R_ct) for ethanol oxidation was substantially reduced from 87.9 Ω on Pt/C to 7.74 Ω on PtPdAu/C demonstrating the superior electrode kinetics behavior of the latter over the other catalysts studied. Thus Au and Pd incorporation into the Pt matrix not only increases the catalytic efficiency of the alloyed catalyst but at the same time effectively reduces the Pt content in the ternary system.     

Catalytic supercritical water gasification of glucose with in-situ generated nickel nanoparticles for hydrogen production

Hydrogen production from catalytic supercritical water gasification of glucose with in-situ generated nickel nanoparticles in a quartz tube reactor is demonstrated. The effects of various operating parameters such as the presence of catalyst, resident time, reaction temperature and feed concentration on the gasification performances are studied. The results show that both the carbon gasification efficiency and the hydrogen gasification efficiency of glucose in supercritical water were improved with in-situ generated nickel nanoparticles as catalyst compared to those without catalyst. The catalyst promotes the water-gas shift reaction and CO methanation reaction, resulting in increased yields of H₂, CH₄ and CO₂ and decreased yield of CO. At the presence of catalyst, 10 wt% glucose solution exhibits the best gasification performances at 500 °C. Highly dispersed nickel nanoparticles identified by high resolution transmission electron microscopy (HRTEM) and X-ray photoelectron spectroscopy (XPS) are assumed to be generated via supercritical hydrothermal synthesis through hydrolysis, dehydration and in-situ reduction. However, the in-situ generated nano-nickel catalyst underwent an activation to deactivation transition due to carbon deposition on the surface of nickel nanoparticles. Regeneration strategies of the deactivated catalysts need further study for practical application.     

Electrocatalytic oxidation of formaldehyde on palladium nanoparticles supported on multi-walled carbon nanotubes

Palladium (Pd) nanoparticles were dispersed on iodinated multi-walled carbon nanotubes (I-MWNTs) by the aqueous solution reduction of Pd(NO₃)₂ with formaldehyde. The structure and nature of the resulting Pd-MWNT composites were characterized by transmission electron microscopy (TEM) and X-ray diffraction (XRD). The electrocatalytic properties of the Pd-MWNT modified glassy carbon electrode (Pd-MWNT/GCE) for formaldehyde oxidation have been investigated by cyclic voltammetry; high electrocatalytic activity of the Pd-MWNT/GCE can be observed. This may be attributed to the high dispersion of palladium catalysts and the particular properties of MWNT supports. The results imply that the Pd-MWNT composite has good potential applications in fuel cells.     

Effect of multi-wall carbon nanotubes supported palladium addition on hydrogen storage properties of magnesium hydride

To improve the hydrogen storage performance of magnesium hydride, multi-wall carbon nanotubes supported palladium (Pd/MWCNTs) was introduced to the magnesium-based materials. Pd/MWCNTs catalysts with different amounts of Pd (20 wt.%, 40 wt.%, 60 wt.%, 80 wt.%) were synthesized by a solution chemical reduction method. Afterwards, Mg₉₅–Pd_m/MWCNTs_5−m (m = 0, 1, 2, 3, 4, 5) were prepared for the first time by hydriding combustion synthesis (HCS) and mechanical milling (MM). It is determined by X-ray diffraction (XRD) analysis that Pd/MWCNTs can significantly increase the hydrogenation degree of magnesium during the HCS process. The microstructures of the composites obtained by transmission electron microscope (TEM) and field emission scanning electronic microscopy (FESEM) analyses show that Pd nanoparticles are well supported on the surface of carbon nanotubes and the Pd/MWCNTs are dispersed uniformly on the surface of MgH₂ particles. Moreover, it is revealed that there is a synergistic effect of MWCNTs and Pd on the hydrogen storage properties of the composites. The Mg₉₅–Pd₃/MWCNTs₂ shows the optimal hydriding/dehydriding properties, requiring only 100 s to reach its saturated hydrogen absorption capacity of 6.67 wt.% at 473 K, and desorbing 6.66 wt.% hydrogen within 1200 s at 573 K. Additionally, the dehydrogenation activation energy of MgH₂ in this system is decreased to 78.6 kJ/mol H₂, much lower than that of as-received MgH₂.     

In-situ deposition and subsequent growth of Pd on SnO2 as catalysts for formate oxidation with excellent Pd utilization and anti-poisoning performance

To prepare Pd catalysts for formate oxidation with superior anti-poisoning performance and Pd utilization, a facile strategy is employed by combining in-situ deposition and subsequent Pd growth. The high resolution transmission electron microscopy is used to observe the morphologies, confirming the existence of Pd/SnO₂ interfaces and the uniform Pd layer on SnO₂ through in-situ deposition. After subsequent growth, the Pd crystalline structure is better developed and the size of identifiable Pd moieties increased, as evidenced by X-ray diffraction (XRD) patterns and high resolution transmission electron microscopy (HRTEM) images. The electrochemical characterization indicates that Pd/SnO₂ interfaces together with increased size of Pd moieties promotes the Pd anti-poisoning performance. Besides, with subsequent Pd growth, the Pd utilization is also improved, as evidenced by the increase in area of Pd oxide reduction peak. Considering the facile preparation, superior performance and flexibility of combining in-situ Pd deposition and subsequent metals growth, the strategy is believed to be of promising potential for wide range catalysts development and application.     

Effect of noble metal species and compositions on manganese dioxide-modified carbon nanotubes for enhancement of alcohol oxidation

By integrating the effects of alloying, chemical composition and support, a series of mono- and bi-metallic catalyst nanoparticles electrodeposited on α-manganese dioxide (MnO₂)-modified carbon nanotube (CNT) supports were synthesized to improve the efficiency of direct alcohol fuel cells. Small and dispersed nanoparticles on the CNT/MnO₂ surfaces with high electrochemically active surface area (ECSA) were successfully obtained in this work. The support materials were characterized by Fourier-transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD), while the as-prepared catalysts were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive spectroscopy (EDS), and X-ray photoelectron spectroscopy (XPS). Cyclic voltammetry (CV) and chronoamperometry (CA) were used to study the activity and stability of the catalysts, respectively. The results showed that a combination of Pt, Pd, Au and MnO₂ on the CNTs significantly affected the topography of the composite catalyst surfaces, and their electrochemical measurements showed excellent electrocatalytic activity toward the reaction. For methanol and ethanol oxidation in acid solution, CNT/MnO₂/1M3Pt (M = Pd or Au) catalysts revealed greater activity improvement compared to the other prepared catalysts. For the bimetallic CNT/MnO₂/xMyPt catalysts, the values of the forward peak current (I_f)) and the ratio of the forward peak current to the reverse peak current (I_f/I_b) were higher, while their onset potentials (E_o) were lower compared to those of the monometallic CNT/MnO₂/4Pt catalyst. Moreover, CO oxidation on these bimetallic catalysts was also confirmed to be poisoning resistant. These results indicate that our prepared catalyst showed excellent electrocatalytic performance, reliability, and stability. The catalytic activity improvement was based upon the unique integrated structural and functional properties and the synergistic effect of different compositions in the catalyst system.