Development of supported bifunctional oxygen electrocatalysts and corrosion-resistant gas diffusion layer for unitized regenerative fuel cell applications

One-pot synthesis of Ir@Pt nanodendrites as highly active bifunctional electrocatalysts for oxygen reduction and oxygen evolution in acidic medium

“…URFCs can be applied not only in space field, but also in an on-site energy storage device used in photovoltaic and wind energy systems [2]. However, one of the most difficult challenges in the development of URFCs is the fabrication of active bifunctional electrocatalysts for both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) at the oxygen electrode [3][4][5][6][7][8][9][10][11]. Although some transition metal oxide can be used as catalyst for both ORR and OER in alkaline medium [12], the practical bifunctional electrocatalyst applied in acidic medium is composed of two efficient electrocatalyst for ORR (e.g., Pt blacks) and OER (e.g., Ir/Ru oxides), respectively.…”

“…Moreover, the conventional preparation methods such as impregnation [10], adsorption/heat treatment [6] or deposition by chemical reduction [5] of one component on the other often lead to the formation of one catalyst component that is relatively large, irregular in morphology and non-uniform in size and composition. For this reason, other researchers [9,11] tried to develop supported Ir and Pt nanoparticles as bifunctional electrocatalysts. However, the exploring of supporting materials with high surface area, high electronic conductivity, appropriate porous structure and corrosion resistance at the same time is difficult.…”

A review of the gas diffusion layer in proton exchange membrane fuel cells: Durability and degradation

“…Nitta et al [41] also confirmed that the GDL permeability decreased as much as one order of magnitude when the GDL was compressed to 65% of the initial thickness. In addition, the degree of the permeability decrease in the GDL varies [97,98] Potential holding and cycling [96] Compression force and carbon corrosion Repetitive compression and three-electrode test [90] Dissolution and erosion by gas flow Immersion in solutions and exposure to excessive gas flow [78] Dissolution and carbon corrosion Immersion in solutions and potential holding [77,80,91] Immersion in solutions and potential cycling [84] with GDL types. Ihonen et al [43] found that the decrease in permeability of the carbon cloth-type GDL is the most severe under increasing clamping pressure because it has the least rigid mechanical structure.…”

“…Huang et al [97] and Song et al [98] used cycling tests of fuel Compression force Controlling GDL thickness by inserting steel gage -Felt Permeability became one-tenth and in-plane and through-plane conductivity increased when the GDL was compressed to 65% [41] Compression force Clamping method -Paper Permeability became one-tenth and contact resistance decreased from 1000 to 25 mohm/cm 2 when the thickness was reduced by half [42] Compression force Compression from 1.6 to 31.1 MPa 1 time Cloth/ felt/paper…”

Two-Dimensional Simulation of Mass Transfer in Unitized Regenerative Fuel Cells under Operation Mode Switching

“…A large amount of literature on experimental PEM URFC research focuses mainly on the preparation techniques for membrane electrode assembly (MEA), the selection of gas diffusion layer (GDL) materials, and the treatment of corrosion-resistant GDL surfaces in terms of content. In addition, system optimization, the effects of structural and operating parameters on the performance of URFCs have also been experimentally investigated [19][20][21][22][23][24]. The literature on modeling of PEM URFC is extremely limited and very few articles have been published.…”