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The advanced electrochemical catalytic activity for oxygen reduction reaction (ORR) based on the octahedral Pt–Ni alloyed catalyst has been demonstrated. However, a means of fabricating catalyst electrodes for use in PEMFCs that is cost-effective, scalable, and maintains the high activity of Pt–Nialloy/C has remained out of reach. Electrophoretic deposition (EPD) is a colloidal production process that has a history of successful deployment at the industrial scale. Here, we report on the facile preparation of an effective and active cathode consisting of Pt–Ni alloy loaded on the carbon cloth substrate using the electrophoretic deposition (EPD) technique, in which the optimum applied voltages and suspension pH are systematically investigated to obtain the highly porous Pt–Nialloy/C catalyst electrode. In a half cell test, the EPD-made Pt–Nialloy/C catalyst electrodes fabricated at 45 V and in a solution with a pH of 9.0 yields the best performances. On the other, as an active cathode, the EPD-made Pt–Nialloy/C electrodes deliver a superior performance in single cell test, with the maximum power density reaches 7.16 W/mgPt, ∼28.1% higher than that of the spray-made Pt/C conventional electrode. The outperformance is attributed to the significantly higher porosity and surface roughness of the EPD-made electrode.

The objective of this study was to fabricate an efficient structural catalyst electrode of Pt/C consisting of double catalyst layers (DCL) with catalyst-ink spray and electrophoresis deposition (EPD) methods. The prepared Pt/C DCL electrode with Pt-dispersed and Pt-concentrated catalyst layers demonstrated better electrochemical properties than individual Pt/C single catalyst layer (SCL) electrodes. An S1E1 DCL electrode with Pt loading weight ratio of 1:1 between the Pt-dispersed and Pt-concentrated layers exhibited a higher electrochemical surface area (ECSA, 57.2 m2/gPt) and lower internal resistance (20 Ω) than an individual Pt-dispersed SCL electrode prepared with only the spray method (S1E0, 31.9 m2/gPt and 132 Ω) and an individual Pt-concentrated SCL electrode prepared with only the EPD method (S0E1, 34.1 m2/gPt and 120 Ω). The S1E1 DCL electrode exhibited 2.1 and 1.7 times higher mass activity for methanol oxidation reaction (MOR) than S1E0 and S0E1 SCL electrodes, respectively (1,230 mA/mgPt for S1E1 vs. 595 mA/mgPt for S1E0 and 715 mA/mgPt for S0E1). In addition, the S1E1 DCL electrode demonstrated high MOR durability after 1,000 sequential cycles while losing 30% activity. Meanwhile, S0E1 and S1E0 SCL electrodes rapidly lost 52% and 55% activity, respectively. These improved electrochemical performances of DCL electrode were owing to the advantages of separating Pt catalysts into two layers, which provides more Pt catalytic active sites to the electrolyte than those in SCL electrodes. Our observation may aid in minimizing the usage amount of Pt catalysts (~0.16 mgPt/cm2) compared to those in present commercial Pt/C composites (~0.3 mgPt/cm2) as well as maximize efficient Pt utilization. More importantly, with regard to proton exchange membrane fuel cell (PEMFC) activity as a crucial in-situ characterization of a catalyst, a membrane electrode assembly (MEA) containing S1E1 as the anode electrode could generate mass maximum power density of 3.84 W/mgPt, 3.6 times higher than the present commercial one (1.07 W/mgPt).

The aim of this work is to study the effect of Nafion content in the microporous layer (MPL) on the electrophoretically deposited Pt/C-Nafion electrode performance. First, the MPLs are prepared with different Nafion ionomer contents (5, 10, 20, 30 and 40 wt%) on the carbon paper substrates. Next, Pt/C-Nafion electrodes are prepared by pulsed electrophoresis deposition (pulsed EPD) from a Pt colloidal solution as a plating bath. The catalytic activities of the prepared Pt/C-Nafion electrodes are evaluated using the cyclic voltammetry (CV) technique for hydrogen oxidation reaction (HOR). Also, a PEMFC single cell test is carried out using the Pt/C-Nafion electrodes prepared with the pulsed EPD method as a cathode. The mass-specific power density for the Pt/C-30wt% Nafion electrode is 1578.8 mW mg Pt − 1 , which is higher than the rest of the Pt/C-Nafion electrodes. The Nafion content in the cathode MPL should affect the performance of the PEMFC, especially at a high current density.

Pt/C double catalyst layer (DCL) electrodes are prepared by pulsed electrophoresis deposition (PED) method from a Pt colloidal solution as a plating bath. The PED is optimized by varying the deposition time in a galvanostatic mode. The catalyst layers of the electrodes prepared by this method are structurally characterized by EDX and SEM studies. The catalytic activities of Pt/C DCL electrodes are evaluated by cyclic voltammetry technique. The loading amount of the Pt catalyst is controlled by varying the deposition time. With the same Pt catalyst loading, the DCL electrode has enhanced catalytic activity than single catalyst layer (SCL) electrode.

Pt/C electrodes are prepared by pulsed electrophoresis deposition (PED) from a Pt colloidal solution as a plating bath. The PED is optimized by varying the duty cycle and deposition time in a galvanostatic mode. The catalytic activities of the Pt/C electrodes are evaluated using the cyclic voltammetry technique. The loading amount of the Pt catalyst is controlled by varying the deposition time. Also, a single cell test is carried out using the Pt/C electrodes prepared with the PED method as a cathode. In the concentration polarization region (i.e., at 0.4 V), the current density for the Pt/C 10 min electrode is 0.845 A cm−2, which is higher than the rest of the Pt/C electrodes.