Thermal annealing synthesis of double-shell truncated octahedral Pt-Ni alloys for oxygen reduction reaction of polymer electrolyte membrane fuel cells

A Review of Strategies to Improve the Stability of Carbon-supported PtNi Octahedral for Cathode Electrocatalysts in Polymer Electrolyte Membrane Fuel Cells

“…Hence, research has focused on enhancing the durability of PtNi octahedral electrocatalysts using methods that suppress Ni leaching, including thirdmetal doping [51,[55][56][57][58], composition control [44,59], halide treatment [60], formation of a Pt layer [52, [61][62][63][64], annealing treatment [48,[65][66][67][68], and size control [69] (Fig. 2).…”

“…Formation of Pt layer PtNi@Pt 2.2L /C 3.1 (10k) 0.6-1.0 0.1 [52] PtNi@Pt 1.5L /C 8.8 (5k), 3.1 (10k) 0.6-1.1 0.1 [61] Annealing treatment PtNi/C@400 o C 2.7 (4k) 0.5-1.0 Not given [68] PtNi/C@300 o C 2.6 (5k) 0.6-1.0 0.1 [65] PtNi/C@400 o C 2.3 (4k), 2 (8k) 0.5-1.0 0.05 [48] Size control PtNi/C_7.4 nm 1.2 (4k) 0.6-1.0 0.05 [69] approximately 1.2 (4k), and research in this area has not been extensively pursued owing to the challenges of particle size control [69]. As for halide treatment, the stability of Br-or Cl-treated PtNi octahedral was improved by a factor of 1.2-3.5 (10k), compared to that of the untreated PtNi octahedral.…”

“…formation of a Pt layer [52,[61][62][63][64], annealing treatment [48,[65][66][67][68], and size control [69], have been explored to overcome the durability issue of PtNi octahedral. The results showed promising improvements in stability during RDE testing.…”

Microstructures and Proton Networks of Ionomer Film on the Surface of Platinum Single Atom Catalyst in Polymer Electrolyte Membrane Fuel Cells

“…However, due to the huge consumption and scarcity of Pt, the cost of catalysts remains a critical issue for the widespread commercialization of PEMFCs . To reduce Pt usage, considerable efforts have been devoted to developing new electrocatalysts, such as Pt-based alloys, , core–shell structures, − and Pt single atom catalysts (SACs), , which can improve the utilization of Pt atoms. Among them, Pt SAC is usually considered as a candidate of the fourth-generation catalyst, due to its excellent activity for the oxygen reduction reaction (ORR) and ultrahigh utilization efficiency of Pt atoms, and thereby attracts lots of attention as an ultralow Pt catalyst.…”

Innovative Insight into O2/N2 Permeation Behavior through an Ionomer Film in Cathode Catalyst Layers of Polymer Electrolyte Membrane Fuel Cells

“…The combination of fuel cell technology and hydrogen energy would definitely promote an efficient utilization of renewable energy, thus greatly alleviating problems concerning environmental pollutions and energy shortages. Polymer electrolyte membrane fuel cells (PEMFCs) possess unique advantages including high energy conversion efficiency, zero emissions, and low-operating temperature and are receiving ever-growing attention in both automotive and power plant fields. − However, the high cost of PEMFCs that is mainly caused by applying a high loading of Pt-based catalysts remains a critical limitation for a large-scale commercialization of PEMFCs. − It is noted that Pt loading can be continuously reduced by developing more active electrocatalysts, while the corresponding decrease in active sites leads to a severe deterioration in local mass transport resistance that results from O 2 molecules crossing the ionomer film in the cathode catalyst layer (CCL), thus lowering the cell performance under high current density. − …”