In terms of the control of Pt nanoparticles, Zhang et al. 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). However, the stack lifetime is only about 4000 h, which is far less than the target of 8000 h. Department of Energy (DOE), the catalyst cost accounts for more than 40% of the whole stack. Although many achievements have been made in recent years, the cost and durability of FC stack are still the major hinders to large-scale applications of PEMFCs. The proton exchange membrane fuel cell (PEMFC) has become the most potential energy resource conversion device for its high-power density, zero emission and high energy conversion efficiency. 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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