Three-dimensional vertical graphene flowers were fabricated using a simple, low-cost, and efficient chemical vapour deposition method with Ni(NO₃)₂ as a catalyst precursor and methane as a carbon precursor. Graphene flowers of up to 10 μm in size with petals of two to seven layers of graphene were obtained. The growth of the vertically aligned graphene flowers was attributed to a columnar growth mechanism. Numerous micropores were observed between the flower petals and irregular mesopores were observed in the interconnected flowers. The charge-transfer resistance of a graphene flower/Ta film was 30.8 Ω. The graphene flowers acted as charge carriers, reducing the charge recombination rate and enhancing electron transport. The vertical graphene flowers showed significant photoelectrocatalytic activity for the degradation of phenol.

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Synthesis of vertical graphene flowers as a photoelectrocatalyst for organic degradation

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