![]() Although its proper specific surface area and porous structure are beneficial to improve the activity of ORR effectively, its low thermal and electrochemical stability are the main reasons for the rapid degradation of catalysis performance. Commercial Vulcan XC-72 carbon black has been widely used in FC ORR. At present, various types of carbon supports have been used in FC, including graphite, graphene, activated carbon, carbon nanofibers, and carbon nanotubes. ![]() The properties of carbon support affect the uniform distribution, particle size, electrochemical active surface area (ECSA) and stability of nanoparticles, which have an important impact on the performance and durability of PEMFCs catalysts. On the other hand, although various types of supports have been used for FC catalysts, such as Ti-nanotube, SiC, SiO 2, TiO 2, Ta-doped Ti-oxide, hybrid material, etc., carbon materials are still the first choice for commercial catalyst supports. The main degradation mechanism of a supported Pt-based catalyst can be attributed to the growth and agglomeration of Pt nanoparticle, the corrosion of carbon support, and the weakening of the interaction between Pt nanoparticles and supports. Although great breakthroughs have been made in non-Pt catalysts, Pt is still the first choice for commercial FC applications due to its excellent electrocatalytic activity. As the most important material of MEA, the durability of catalyst plays an important role in the lifetime of the stack, and further research is needed. The three-phase boundary (TPB) composed of a catalyst, ionomer and reaction gas is the place where the electrochemical reaction takes place in the stack (i.e., the reactive active point). Due to the important role in the stack, membrane electrode assembly (MEA) is usually called the FC stack’s heart. Under actual working conditions, the stack performance decreases gradually due to the decay of various components or materials, including proton exchange membrane (PEM), catalyst, gas diffusion layer (GDL) and bipolar plate (BPP). Therefore, Pt/GBP is a valuable and promising catalyst for PEMFC, and considered as an alternative to classical Pt/C. In addition, the post morphology characterizations indicate that the structure and particle size of the Pt/GBP catalyst remain unchanged during the dynamic testing protocol, implying its better stability under dynamic load cycles. The durability of the stack is improved because of the durability and stability of the catalyst. After the 1003-hour durability test, the proton exchange membrane fuel cell (PEMFC) stack with Pt/GBP presents a slow voltage degradation rate of 5.19% and 36 μV h −1 at 1000 mA cm −2. Especially, the survival time of Pt/GBP-membrane electrode assembly (MEA) reaches 205 min, indicating that it has better reversal tolerance. The results of a half-cell accelerated degradation test (ADT) of two protocols and a single-cell ADT show that, Pt/GBP catalyst has excellent stability and durability compared with commercial Pt/C. Graphitized black pearl (GBP) 2000 supported Pt nanoparticle catalysts is synthesized by a formic acid reduction method.
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