Pulsed Electrodeposition of Highly Porous Pt Alloys for use in Methanol, Formic Acid, and Glucose Fuel Cells

Abstract

We demonstrate an electrodeposition process for the fabrication of highly porous PtCu alloy anodes. In the fabrication process, Pt and different amounts of a second noble metal (Pd, Ru, Au) are repeatedly co‐deposited with Cu from an aqueous electrolyte, followed by selective dealloying of Cu. In this way, highly porous PtCu alloys with roughness factors ranging from 400 to 4000 can be obtained. In all cases, both noble‐metal partners are present on the electrode surface, whereas the majority of copper is likely buried underneath. In addition, we can show that H desorption and CO stripping yield substantially different roughness factors, even when applied to PtCu anodes. Hence, when using or comparing results from different stripping methods, a calibration is required. Compared to PtCu anodes, small additions of Ru (ca. 3 at% Ru) lead to significantly enhanced catalytic activity for the electro‐oxidation of formic acid and methanol, whereas Au‐rich PtCu−Au alloys (ca. 75 at% Au) exhibit significantly improved electrocatalytic activity for glucose oxidation. In some cases, large variations impede the identification of significant differences in electrocatalytic activity. To reduce process variability and to increase the specific surface area, further optimization of the fabrication process is required. Similarly, the deposition of defined alloy compositions will require further investigation, as the composition of electrolyte and deposited alloy do not directly correspond.

Role of Ultrathin Carbon Shell in Enhancing the Performance of PtZn Intermetallic Nanoparticles as an Anode Electrocatalyst for Direct Formic Acid Fuel Cells

“…In general, the reaction pathway of FAOR is closely related to the anti‐poisoning ability of the electrocatalyst. Thus, to further investigate the anti‐poisoning ability of the electrocatalysts, the ratio of the forward oxidation current peak (j f ) to the reverse current peak (j b ), that is j f /j b , was calculated as a parameter reflecting the CO tolerance ability of the electrocatalyst ,. The j f /j b values are 0.37, 1.14, 1.12 for Pt/C, PtZn iNPs and UCS−PtZn iNPs electrocatalysts, respectively.…”

“…Thus, to further investigate the anti-poisoning ability of the electrocatalysts, the ratio of the forward oxidation current peak (j f ) to the reverse current peak (j b ), that is j f /j b , was calculated as a parameter reflecting the CO tolerance ability of the electrocatalyst. [44,45] The j f /j b values are 0.37, 1.14, 1.12 for Pt/C, PtZn iNPs and UCSÀ PtZn iNPs electrocatalysts, respectively. The observed higher j f /j b values of PtZn intermetallic electrocatalysts than that of commercial Pt/C strongly confirm that intermetallic electrocatalysts are less susceptible to CO poisoning than Pt/C.…”

Highly Porous Platinum Electrodes for Dry Ear-EEG Measurements

“…The electrodeposition process used in this work was adapted from Frei et al [17], with minor changes to suit the application. The experiments were conducted in a three-electrode setup using the Solartron Analytical 1287A potentiostat function.…”

“…In this study, different materials are compared due to their electrochemical properties and a platinum (Pt) based ear-electrode is presented with highly increased active surface with minimal impedance in the relevant frequency domain. An electrodeposition process is used which creates highly porous platinum surfaces through the iterative co-deposition of Pt and copper (Cu), whereby Cu is released again after each cycle [17]. Thus, defined surface structures of different heights can be produced.…”

Effects of the Synthesis Method and Promoter Content on Bismuth‐Modified Platinum Catalysts in the Electro‐oxidation of Glycerol and Formic Acid

“…The fuel cell systems have obtained growing attentions facing with the serious energy and environmental problems. Among the fuel cells, the direct alcohol fuel cells (DAFCs) and direct formic acid fuel cells (DFAFCs) have been considered as promising power sources because of its superiorities of high theoretical energy densities, facile transportation and storage . For DAFCs, electro‐oxidation of glycerol is attractive owing to its biorenewable and non‐toxic properties,, as well as the potential to cogenerate the electrical energy and transform into lots of high‐value‐added fine chemicals …”