Fabrication Of Phthalocyanine Covalently Functionalized Graphene Composites And Their Application For The Cathodic Catalyst In Fuel Cell

Direct methanol fuel cells (DMFCs) are considered to be a promising green energy generation technology, in which catalysts for oxygen reduction reaction (ORR) play a key role. Pt-based materials or Pt is known to be the best electrocatalyst for4-electron reduction of O2. However, it suffers from not only scarcity and high-cost but also intolerance to the crossover effect and instability. Thus, it is necessary to find efficient, durable and cheap alternatives to Pt and Pt-based catalysts.In this dissertation, we fabricated four novel metallophthalocyanine/graphene composite catalysts for the oxygen reduction reaction, in which CoTNPc/PGr and CoPc(TP)4/PGr composites were fabricated by in situ solvothermal synthesis method, FePc(CP)4/PGr and FePc(TP)4/PGr via solvothermally assisted π-π assembly method.The physicochemical properties of fabricated metallophthalocyanine/graphene composite catalysts were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), ultraviolet-visible (UV-vis) absorption spectroscopy, fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS), respectively. The electrocatalytic performance of the metallophthalocyanine/graphene composites toward the ORR was evaluated using cyclic voltammetry and linear sweep voltammetry methods. The results showed that the assembled CoTNPc/PGr and FePc(CP)4/PGr catalysts display excellent catalytic activity for ORR, which is comparable to that of commercial Pt/C catalyst, while the obtained CoPc(TP)4/PGr and FePc(TP)4/PGr composites possess higher catalytic activity than Pt/C. The fabricated four novel catalysts for ORR display high activity, good long-term stability, excellent tolerance to the crossover effect, and following a4-electron process, which may be used as promising Pt-free ORR catalysts in alkaline direct methanol fuel cell (DMFC).