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.     

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.     

The effect of CuO on a Pt−Based catalyst for oxidation in a low-temperature fuel cell

Electrocatalytic oxidation of methanol, ethanol, and formic acid has currently attracted research attention for low-temperature fuel cells. However, the efficiencies of these fuel cells mainly depend on the electrocatalytic activities of Pt-based anodic catalysts due to the problems of low kinetics for small organic molecule electro-oxidation. An anode catalyst can be developed by the addition of some metal oxides into a Pt-based catalyst, which can effectively promote the electro-oxidation of fuels based on small organic molecules. In this work, a nanocomposite catalyst consisting of multi-wall carbon nanotubes (CNTs), copper oxide (CuO) and Pt nanoparticles was synthesized and used to improve fuel cell oxidation. Due to its low cost and oxophilic character, the metal oxide can play a major role in the oxidation of CO. The synthesis of xPt?yCuO/CNT electrocatalysts was executed through two steps: supporting of CuO nanoparticles on CNTs by the alcothermal method followed by Pt loading onto the prepared CuO/CNT by chemical reduction. The as-prepared catalysts were physically characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Raman spectroscopy, and electrochemical measurements. The results demonstrate that CuO is well dispersed onto the CNTs and that this oxide can further interact with the active Pt present on the as-prepared catalyst composites. The activity of various xPt?yCuO/CNT electrocatalysts was determined by cyclic voltammetry (CV), where x and y are the mass ratios of Pt and CuO, respectively. The presence of CuO was found to significantly contribute to enhanced electroactivity towards oxidation reactions. The 1Pt–3CuO/CNT electrocatalyst is a capable catalyst for improving low-temperature fuel cell applications.     

Catalytic activity,stability and impedance behavior of PtRu/C,PtPd/C and PtSn/C bimetallic catalysts toward methanol and formic acid oxidation

PtRu, PtPd and PtSn with weight ratios of (2:1) on carbon black (Vulcan XC-72) supported bimetallic catalysts were prepared by using microwave method via chemically reduction of H₂PtCl₆·6H₂O, RuCl₃, PdCl₂ and SnCl₂·2H₂O precursors with ethylene glycol (EG). These prepared catalysts were systematically investigated and obtained results were compared with commercial Pt black, PtRu black catalysts and with each other. The catalysts were characterized with XRD, ICP-MS, EDS and TEM. The electrocatalytic activities, stability and impedance of the catalysts were investigated in sulfuric acid/methanol and sulfuric acid/formic acid mixtures using electrochemical measurements. The results showed that PtSn/C catalyst showed comparable activity and durability with commercial Pt/C catalyst toward methanol oxidation. The synthesized PtRu/C catalyst was found to completely oxidize methanol and it showed more catalytic activity than commercial PtRu catalyst. Bimetallic PtPd/C catalyst gave better activity than both commercial Pt black and synthesized Pt/C catalyst for oxidation of formic acid. Higher electrochemical active surface areas were obtained with supported bimetallic catalysts.     

Use of graphene-supported manganite nano-composites for methanol electrooxidation

Binary nano-composites of palladium and a metal (Fe or Cu) manganite on graphene nanosheets (GNS) have been prepared by a microwave-assisted polyol reduction method and investigated as electrocatalysts for the methanol oxidation reaction (MOR) in 1 M KOH at 25 °C. Structural and electrocatalytic surface characterizations of composites are carried out by X-ray diffraction, transmission electron microscopy, X-ray photoelectron microscopy, cyclic voltammetry and chronoamperometry. Results show that new composite catalysts, particularly 40 wt%Pd–x wt%FeMn₂O₄/GNS (where x = 5, 8, 10 & 15) are MOR active and that the activity is the greatest with the catalyst containing 8 wt% of the oxide. The composite, Pd–8 wt%FeMn₂O₄/GNS, exhibits much superior catalytic activity as well as stability compared to the base (Pd/GNS) electrode. The enhanced catalytic activity and stability of the Pd/GNS catalyst in presence of the oxide can be ascribed to increased population of adsorbed OH⁻ ions/OH radicals at the electrode surface.     

Effect of metal particle size and Nafion content on performance of MEA using Ir-V/C as anode catalyst

Ir and Ir-V nanoparticles were synthesized in ethylene glycol using IrCl₃ and NH₄VO₃ as the Ir and V precursors, respectively. These nanoparticles were evaluated as anode catalysts in proton exchange membrane fuel cells (PEMFCs). A thermal treatment of the catalysts at 200 °C in a reducing atmosphere leads to very high electrocatalytic activity for the hydrogen oxidation reaction. The fuel cell performance reveals an optimal Nafion ionomer content of 25% in the catalyst layer used for the MEA fabrication. The electrocatalytic effects related to the change in the electrocatalyst structure are discussed based on the data obtained by X-ray diffraction (XRD) and transmission electron microscopy (TEM). In addition, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) techniques are used in-situ to assess the kinetics of hydrogen oxidation on the surface of these catalysts. A maximum power density of 1016.6 mW cm⁻² was obtained at 0.598 V and 70 °C with an anode catalyst loading of 0.4 mg (Ir) cm⁻². This performance is 50.7% higher than that for commercially available Pt/C catalysts under the same conditions. In addition, we also tested the anode catalyst with a low loading of 0.1 mg (Ir) cm⁻², the maximum power density is 33.8% higher than that of the commercial Pt/C catalyst with a loading of 0.4 mg (Pt) cm⁻².     

Investigation of the effect of carbonaceous supports on the activity and stability of supported palladium catalysts for methanol electro-oxidation reaction

In this study, nitrogen doped graphene (NG) and multi-walled carbon nanotubes (MWCNT) were used as supporting materials for palladium active phase to investigate their performance in direct methanol fuel cells (DMFCs). The facile and low temperature solvothermal method was used for the synthesis of NG. Palladium nanoparticles were deposited on the surface of NG and MWCNT by a modified polyol reduction method. The morphologies and microstructures of the prepared catalysts were characterized by scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and X-ray diffraction. Also, cyclic voltammetry, chronoamperometry, and electrochemical impedance spectroscopy were carried out to evaluate the electrocatalytic activity and the durability of the obtained catalysts towards methanol oxidation reaction. Pd/NG catalyst had a better activity and durability of methanol electrocatalytic oxidation rather than Pd/MWCNT catalyst, which is related to good dispersion of Pd nanoparticles on the surface of nitrogen doped graphene and the physicochemical characteristics of NG.     

A polyoxometalate-deposited Pt/CNT electrocatalyst via chemical synthesis for methanol electrooxidation

Polyoxometalate anion PMo₁₂O₄₀³⁻ (POM) is chemically impregnated into a Pt-supported carbon nanotubes (Pt/CNTs) catalyst that is prepared via a colloidal method. The POM-impregnated Pt/CNTs catalyst system (Pt/CNTs-POM) shows at least 50% higher catalytic mass activity with improved stability for the electrooxidation of methanol than Pt/CNTs or POM-impregnated Pt/C (Pt/C-POM) catalyst systems. The enhancement in electrochemical performance of the Pt/CNTs-POM catalyst system can be attributed to the combined beneficial effects of improved electrical conductivity due to the CNTs support, highly dispersed Pt nanoparticles on the CNTs, and increased oxidation power of the polyoxometalate that can assist oxidative removal of reaction intermediates adsorbed on the Pt catalyst surface.     

Electrodeposited Pd nanoparticles on polypyrole/nickel foam for efficient methanol oxidation

The present work describes the Ni foam (Ni–F)/polypyrrole (PPy)/palladium (Pd) (Ni–F/PPy/Pd) multilayered catalysts via a facile electrochemical technique. Potentiostatic deposition of PPy on the surface of Ni–F is followed by galvanostatic deposition of Pd nanoparticles on Ni–F/PPy acted as supports for electrochemical deposition of Pd nanoparticles. The produced catalysts are utilized for electrocatalytic methanol oxidation in alkaline media. Chronoamperometry (CA), cyclic voltammetry (CVs), and electrochemical impedance spectroscopy (EIS) techniques are used to examine the electrocatalytic performance of Ni–F/PPy/Pd based electrodes for methanol oxidation. The polypyrrole modification on Ni–F leads to an improvement in the electrocatalytic activity of the Ni-F/PPY-Pd catalysts toward methanol oxidation. As an open-pored, porous metal with high electrical conductivity, nickel foam produces a substantial amount of active area during the modification of Pd and polypyrrole, which results in significant catalytic activity and a rapid rate charge transfer reaction kinetics on methanol oxidation. The Ni–F/PPy/Pd10 catalyst exhibits enhanced specific activity than its counterparts and a reduced onset potential for methanol oxidation, as well as a low Tafel slope. Based on these results, Ni–F/PPy/Pd10 is suggested as a good material for the anode in the electrocatalytic oxidation of methanol.     

Pt electrodeposited on CeZrO4/MCNT as a new alternative catalyst for enhancement of ethanol oxidation

Electrocatalytic preparation of Pt-based nanocomposites has been investigated for improvement of direct ethanol fuel cells (DEFCs). In this study, new alternative catalysts of Pt-decorated cerium zirconium oxide-modified multiwalled carbon nanotubes (Pt/CeZrO₄/MCNT) were successively prepared to improve the activity of the ethanol oxidation reaction (EOR). The prepared CeZrO₄ with a face-centered cubic (fcc) structure compatibly dispersed onto MCNT provides abundant active Pt sites for highly active catalysts. The fcc-structured Pt was also satisfactorily decorated onto CeZrO₄/MCNT, resulting in highly active Pt. The Ce⁴⁺/Ce³⁺ redox property can promote oxygen vacancies to improve the electrochemical activity for oxidation of carbonaceous species. An increase in roughness and a stabilized catalyst structure can also be produced by inserting Zr⁴⁺ into the ceria metal oxide. The prepared Pt/20%CeZrO₄/MCNT catalysts present excellent electrochemical active surface area, mass activity, CO tolerance and high electron kinetic transfer with low resistance and high stability over commercial PtRu/C toward EOR. This promising catalyst material could be introduced to enhance the anodic oxidation reaction in DEFCs.     

Carbon supported Pt-shell modified PdCo-core with electrocatalyst for methanol oxidation

A catalyst for anode oxidation of methanol, carbon supported pseudo-core-shell PdCo@Pt particles with Pt shell is prepared via a two-step procedure, which consists of an organic colloid method and a surface replacement reaction step. Transmission electron microscopy (TEM) and X-ray diffraction (XRD) are used for the catalysts characterization. The electrochemical surface areas (ECSA) are 6 and 4 times as large as those of Pt/C and PtRu/C catalysts, respectively. Furthermore, based on the Pt mass, the cyclic voltammetry (CV) and chronoamperometry results demonstrate that the electrocatalytic activity and stability of the PdCo@Pt/C catalyst for methanol oxidation are much higher than those of the Pt/C and PtRu/C catalysts. The PdCo@Pt/C catalyst is better utilization of Pt than pure Pt and Pt-based alloy catalysts.     

A UPD-spontaneous redox approach to the preparation of monolayer palladium on reduced graphene oxide-supported gold nanoparticles for ethanol electrooxidation in alkaline media

Monolayer Pd on electrochemical-reduced graphene oxide supported Au nanoparticles (m-Pd–Au/ERG) was designed by a simple and effective route, which produces electrocatalyst with a considerably low Pd loading and good electrocatalytic performance for ethanol oxidation. The as-prepared m-Pd–Au/ERG nanocompostie was characterized by scanning electron microscopy and energy-dispersive X-ray spectroscopy. The results show that high-density m-Pd–Au nanoparticles are dispersed on the surface of ERG uniformly. The electrochemical activities of the as-prepared nanocomposites toward ethanol oxidation in alkaline media were investigated by using cyclic voltammetry and chronoamperometric technique. The results demonstrate that the m-Pd–Au/ERG catalyst shows much higher electrocatalytic activity, stronger tolerance to CO than the m-Pd–Au and b-Pd–Au/ERG catalysts for ethanol oxidation.     

Enhanced catalytic efficiency of bimetallic Pt-Pd on PAMPs-modified graphene oxide for formic acid oxidation

A catalyst composed of 2-acrylamido-2-methyl-1-propane sulfonic acid (PAMPs) modified graphene oxide (GO) as the supporting material (PAMPs/GO) and electrodeposited monometallic and bimetallic catalysts (Pt and/or Pd) as the active catalytic component was fabricated to enhance the formic acid oxidation. The morphology of the prepared catalysts was characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), while the chemical compositions were identified by energy-dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). Functional groups of the supporting materials and catalysts were identified by Fourier transform infrared (FT-IR) spectroscopy. The electrochemical measurements of the synthesized catalysts were evaluated by cyclic voltammetry (CV) and chronoamperometry (CA), respectively. The kinetics of formic acid oxidation on the synthesized catalysts were determined by Tafel extrapolation of linear sweep voltammograms. The CO tolerance of the electrocatalyst was examined by CO stripping measurements. The results showed that the catalysts with PAMPs exhibited much higher electrocatalytic activity and longer-term stability for formic oxidation than the catalyst without PAMPS. In addition, the 3Pt3Pd/10%PAMPs/GO catalyst showed the greatest catalytic activity, stability, and fastest charge transfer kinetics when compared to other bimetallic catalysts and monometallic catalysts. In conclusion, modifying the GO surface with PAMPs can improve the efficiency of the electrocatalyst activity of Pt/Pd catalysts. The 3Pt3Pd/10%PAMPs/GO catalyst is a promising electrocatalyst for the enhancement of formic acid oxidation.     

Design and preparation of CNT@SnO2 core-shell composites with thin shell and its application for ethanol oxidation

A novel electrocatalyst structure of carbon nanotubes (CNT) coated with thin SnO₂ and Pt (Pt/(CNT@SnO₂)) is reported. The CNT@SnO₂ composites with a thin shell (about 2 nm) are prepared by a simple chemical-solution method. The Pt/(CNT@SnO₂) catalyst is prepared by first microwave heating H₂PtCl₆ in NaOH ethylene glycol solution and then depositing Pt nanoparticles onto CNT@SnO₂ composites. High-resolution transmission electron microscopy and X-ray diffraction show that crystalline SnO₂ of about 2 nm thickness is coated uniformly on the surface of the CNTs. Pt nanoparticles of about 3.2 nm in diameter are homogenously dispersed on the SnO₂ surface. Electrochemical studies were carried out using cyclic voltammetry and chronoamperometry. The results showed that Pt/(CNT@SnO₂) catalysts have much higher catalytic activity and CO-tolerance for ethanol electro-oxidation than that of Pt/CNT.     

Enhancement of anodic oxidation of formic acid on Pd–Fe bimetallic nanoparticles by thermal treatment

The surface composition and catalytic properties of Pd–Fe bimetallic catalysts with identical bulk composition can be continuously tuned by treatment at different temperatures. The activity of these catalysts in formic acid oxidation was related to the treatment temperature. The thermal treatment temperatures ranged from 400 to 600 °C. The Pd–Fe nanoparticles are characterized by an array of analytical techniques including TEM (transmission electron microscopy), XRD (X-ray diffraction), ICP (inductively coupled plasma) and HS-LEIS (low energy ion scattering spectroscopy). The electrocatalytic activity is examined using cyclic voltammetric and chronoamperometric measurements. The Pd–Fe/C catalyst with 500 °C shows the highest electrocatalytic activity for formic acid oxidation, with a current activity 3 times higher than that of before treated Pd–Fe/C catalyst, 5.6 times higher than that of commercial Pt/C catalyst. The migration of Pd to the surface on the nanoparticle catalysts as well as the electrochemical active surface area of the PdFe–H catalysts was shown to play a major role in enhancing the electrocatalytic activity for catalyst. These findings provided important insights into the correlation between the electrocatalytic activity and the treatment temperature of the nanoengineered bimetallic catalysts.     

Remarkable electrocatalytic activity of Ni-nanoparticles on MOF-derived ZrO2-porous carbon/reduced graphene oxide towards methanol oxidation

In the present work, a porous carbonaceous platform containing zirconium oxide was used for spreading Ni nanoparticles, and applied to methanol oxidation. The platform was obtained by calcination of a metal-organic framework (MOF) attached to graphene oxide. Nickel nanoparticles were then deposited on the nanocomposite by chemical reduction from a Ni²⁺ solution. The obtained electrocatalyst was characterized by different methods. An excellent electrocatalytic behavior was observed towards methanol oxidation in alkaline medium (j ~ 240 mA cm^?2 or ~ 626 mA mg^?1 in 1.0 M methanol). The results of methanol oxidation by various electrochemical studies (cyclic voltammetry, electrochemical impedance spectroscopy, chronoamperometry and chronopotentiometry) revealed the effective synergy between reduced graphene oxide, porous carbon material, ZrO₂ metal oxide and Ni nanoparticles. Good durability and stability of the proposed electrocatalyst and significantly increased current density of methanol oxidation suggest it as a potential alternative for Pt-based electrocatalysts in direct methanol fuel cells.     

High dispersion and electrocatalytic activity of Pd/titanium dioxide nanotubes catalysts for hydrazine oxidation

Pd/titanium dioxide nanotubes (Pd/TiO₂-NTs) catalysts were prepared by a simple reduction method using TiO₂-NTs as support. The structure and morphology of the resulting Pd/TiO₂-NTs were characterized by transmission electron microscopy and X-ray diffraction. The results showed that Pd nanoparticles with a size range from 6 to 13 nm were well-dispersed on the surface of TiO₂-NTs. The electrocatalytic properties of Pd/TiO₂-NTs catalysts for hydrazine oxidation were also investigated by cyclic voltammetry. Compared to that of pure Pd particles and Pd/TiO₂ particles, Pd/TiO₂-NTs catalyst showed much higher electrochemical activity. This may be attributed to the uniform dispersion of Pd nanoparticles on TiO₂-NTs, smaller particle size and unique properties of TiO₂-NTs support. In addition, the mechanism of hydrazine electrochemical oxidation catalyzed by Pd/TiO₂-NTs are also investigated. The oxidation of hydrazine was an irreversible process, which might be controlled by diffusion process of hydrazine.     

Electrooxidation of ethanol and glycerol on carbon supported PtCu nanoparticles

Four carbon supported PtCu nanostructured catalysts with Pt:Cu atomic ratios of 1:3.20, 1:2.23, 1:0.61 and 1:0.35 were synthesized by a two-step route, involving the chemical reduction of Cu ions on the carbon support, followed by the partial galvanic replacement of Cu atoms by Pt. Bimetallic nanostructured particles with average sizes in the range of 2.3–3.2 nm were obtained. The bimetallic catalysts with surface Pt contents between 20 and 55 at. % were formed by a Cu-rich core surrounded by a Pt-Cu shell, while that with the highest Pt content presented a uniform alloy structure instead of a core-shell arrangement. The electrocatalytic performance of the as-prepared materials toward ethanol electrooxidation in acid and alkaline media and glycerol oxidation in alkaline environment was investigated by cyclic voltammetry and chronoamperometry. It was observed that the electrocatalytic activity of PtCu nanoparticles was found to depend on the surface composition, platinum utilization efficiency, structure and Pt ensemble. Among the as-prepared catalysts, Pt_0·62Cu_0·38/C core-shell material showed the best performance for ethanol oxidation in both acid and alkaline environments, while Pt_0·24Cu_0·76/C and Pt_0·31Cu_0·69/C core-shell catalysts exhibited the highest activity for glycerol oxidation in alkaline medium. The electrochemical results showed that the catalytic activity of the bimetallic Cu@PtCu core-shell nanostructured nanoparticles is between four and ten times higher than that of a commercial Pt_0·51Ru_0·49/C catalyst.     

A facile method to synthesize well-dispersed PtRuMoOx and PtRuWOx nanoparticles and their electrocatalytic activities for methanol oxidation

PtRuMoO_x and PtRuWO_x catalysts supported on multi-wall carbon nanotubes (MWCNTs) are prepared by ultrasonic-assisted chemical reduction method. XRD measurements indicate that Pt exists as face-centered cubic structure, Ru is alloyed with platinum, and the metal oxides exist as an amorphous structure. TEM pictures show that PtRuMoO_x and PtRuWO_x catalysts are well dispersed on the surface of MWCNTs with the particle size of about 3 nm and a narrow particle size distribution. The electrochemical properties of the catalysts for methanol electrooxidation are studied by cyclic voltammetry (CV), chronoamperometry (CA) and chronopotentiometry (CP). The onset potentials for methanol oxidation on PtRuMoO_x and PtRuWO_x are more negative than that of pure Pt catalyst, shifting negatively by about 0.20 V and have better electrocatalytic activities than PtRu/MWCNTs.     

Pt-based bimetallic catalysts for SO2-depolarized electrolysis reaction in the hybrid sulfur process

SO₂-depolarized electrolysis (SDE) is pivotal in the hybrid sulfur process, which is a promising approach for mass hydrogen production without CO₂ emission. The anode overpotential of SDE is the key component of electrolysis potential. This factor can be reduced by improving anode reaction kinetics. Such improvement is commonly achieved by employing Pt/AC as anode electrode and catalyst, thus also improving economic and electrocatalytic performances. In this work, anode catalysts for SO₂ oxidation reaction are experimentally studied. Platinum-based bimetallic catalysts, including Pt–Pd/C, Pt–Rh/C, Pt–Ru/C, Pt–Ir/C, and Pt–Cr/C, are prepared and characterized. Their electrochemical characteristics for SDE in a once-through mode are investigated in SO₂-saturated 30 wt% sulfuric acid at room temperature by various approaches such as cyclic voltammetry, linear sweep voltammetry, and polarization curves. Results show that 60 wt% Pt–Cr/C exhibits the highest electrocatalytic activity for SDE. Further studies on the metal proportion in Pt–Cr/C show that at a Pt:Cr atomic ratio of 1:2, this bimetallic catalyst demonstrates equal or even better electrolysis performance than 60 wt% Pt/C at a significantly lower economic cost.