Editors' Choice—Electrodeposition of Platinum on Titanium Felt in a Rectangular Channel Flow Cell

Abstract

Highly porous platinized titanium substrates are attractive electrode materials for industrial electrochemical processing and electrochemical energy storage. The electrodeposition of platinum on titanium felt was carried out in a divided, rectangular channel flow cell from an alkaline bath without additives. The morphology and spatial distribution of the platinum deposits in the porous material were analyzed using SEM and EDS microscopy in addition to X-ray computed tomography (CT). The electroplated surface area was estimated from the charge transfer current ratio for Ce(IV) reduction and related to a theoretical electrosorbed hydrogen monolayer surface area. The platinized titanium felt showed a significant enhancement of active surface area in comparison to conventional electrode materials. Although platinum was present throughout the porous electrode, CT revealed heterogeneous deposits accumulating in regions near the membrane (during electrodeposition), as a result of the potential distribution in the felt material and flowing electrolyte. Uniform platinum coatings are possible on thin titanium felt under 200 μm thick, by either potentiostatic or galvanostatic electrodeposition.

Pressure drop through platinized titanium porous electrodes for cerium‐based redox flow batteries

“…Pt/Ti plate and Pt/Ti mesh electrodes were sourced externally, while Pt/Ti felt and Pt/Ti micromesh electrodes were electroplated with platinum in a flow cell using alkaline plating solutions. A detailed description of their manufacture has been provided in previous work …”

“…The Pt/Ti felt electrode underwent three electroplating steps, and the resulting electrodes were termed: Pt/Ti felt “A,” Pt/Ti felt “B,” and Pt/Ti felt “C,” which had average volumetric Pt loadings of 4.6, 9.3, and 18.3 mg cm −3 , respectively . Computer tomography imaging revealed that Pt was deposited in a zone approximately 200 μm deep from the outer surface of the felt electrodes, in a plane opposite to the current collector . As seen in Figure d, this Pt‐coated zone was still porous and represented no more than 5.6% of the cross‐sectional area of the electrode; see Table .…”

Developments in electrode design: structure, decoration and applications of electrodes for electrochemical technology

“…Similar 3D Pt/Ti electrodes, which are typically coated by a 3.5‐µm‐thick electrodeposit of platinum, have been used for the positive electrode of a Zn‐Ce hybrid redox flow battery . Pt/Ti expanded mesh and in‐house micromesh and felt were examined, their noble metal distribution studied by X‐ray computed tomography . Limiting current measurements were made for the reduction of Ce(IV) ions in an electrolyte containing 0.1 mol dm −3 Ce(IV) and 0.7 mol dm −3 Ce(III) in 4 mol dm −3 methanesulfonic acid at 25 °C.…”

“…45 Pt/Ti expanded mesh and in-house micromesh and felt were examined, their noble metal distribution studied by X-ray computed tomography. 31,46 Limiting current measurements were made for the reduction of Ce(IV) ions in an electrolyte containing 0.1 mol dm −3 Ce(IV) and 0.7 mol dm −3 Ce(III) in 4 mol dm −3 wileyonlinelibrary.com/jctb methanesulfonic acid at 25 ∘ C. The current enhancement factor observed over 1-16 cm s −1 at the porous electrodes was between 15 and 20 for the mesh, between 52 and 62 for the micromesh stack and between 108 and 160 for the felt. 45 The volumetric mass transfer coefficient, k m A e was as high as 0.1 s −1 at a flow velocity of 12 cm s −1 past the felt, compared to a value of 0.0007 s −1 for the foil under similar conditions.…”

Characterization of Multinanoporous Pt-TiO<sub>2</sub> Thin Films Fabricated by a Three-Step Electrochemical Technique

“…This electron's scavenging efficaciously delays the charge carrier's recombination by improving the quantum yield and the photocatalytic efficiency. On the semiconductor surface the holes typically generate hydroxyl radical species ( OH) that are among the strongest oxidizers known (the standard electrode potential: 2.8V) [2][3][4][5][6].…”