A novel
metal organic framework (MOF)-based composite was synthesized
on a Cu substrate via a two-step route. An amorphous iron oxide/hydroxide
layer was first deposited on a Cu foil through a sol–gel process;
then, Fe-NH2-Mil-101 was grown using both the iron oxide/hydroxide
matrix, which provided the Fe3+ centers needed for MOF
formation, and 2-aminoterephthalic acid ethanol solution. This innovative
synthetic strategy is a convenient approach to grow metal oxide/hydroxide
and MOF composite films. Structural, chemical, and morphological characterizations
suggest that the obtained composite is made up of both the α-FeOOH
goethite and the NH2-Mil-101 phases featuring a hybrid
heterostructure. The electrochemical features of the composite structure
were investigated using electrochemical impedance spectroscopy. The
impedance behavior of the α-FeOOH/NH2-Mil-101 films
indicates that they can be used as efficient high surface area metal
hydroxide/MOF-based electrodes for applications such as energy storage
and sensing.