Carbonization of Fe-Based Metal Organic Frameworks with Mesoporous Structure as Electrocatalyst for Catalysis of Oxygen to Hydrogen Peroxide.

H2O2 production from electron reduction of oxygen (O2) is considered to be a potential alternative to the current anthraquinone process. Herein, we reported a mesoporous catalyst with iron-carboxylate metal-organic framework (MOF) as precursors to catalyze O2 to hydrogen peroxide (H2O2). Iron-carboxylate MOF (Fe-MOF) was synthesized by the novel cetyltrimethylammonium bromide (CTAB)-citric acid (CA) double-template method. The SEM and SAXD results revealed octahedral structure of the nanoparticles, as well as the presence of mesopores in the Fe-MOF, while the molar ratio 2.03 of CTAB to CA that resulted in the largest value (0.914 cm3g-1) of the mesopores in the Fe-MOFs. The pyrolysis of Fe-MOF with the largest amount of mesopores resulted in its carbonization and produced γ-Fe2O3@carbon material, significantly reduced the BET surface area from 3036 m2 g-1 to 387 m2 g-1, but increased the average pore diameter up to 5.78 nm and disintegrated their octahedral structures to an irregular morphology of Fe-MOF (550), and modified the carbon matrix with trace oxygen and metal oxides. The γ-Fe2O3@carbon material possessed mesoporous structure, with predominant graphitic carbon in the matrix (graphite to amorphous carbon ratio 0.79), which contributed to increased potential for electron reduction of O2 through a 2e- electron transfer pathway.