Liu Rong, Ran Ling, Niu Bei, Wei Yi
School of Medicine and Nursing, Chengdu University, Chengdu 610106, China.
School of Physics, Dalian University of Technology, Dalian 116024, China.
J Nanosci Nanotechnol. 2018 Jul 1;18(7):4667-4674. doi: 10.1166/jnn.2018.15311.
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.
通过氧（O₂）的电子还原产生过氧化氢（H₂O₂）被认为是当前蒽醌法的一种潜在替代方法。在此，我们报道了一种以铁羧酸盐金属有机框架（MOF）为前驱体的介孔催化剂，用于催化O₂生成过氧化氢（H₂O₂）。铁羧酸盐MOF（Fe-MOF）通过新型十六烷基三甲基溴化铵（CTAB）-柠檬酸（CA）双模板法合成。扫描电子显微镜（SEM）和小角X射线衍射（SAXD）结果揭示了纳米颗粒的八面体结构以及Fe-MOF中介孔的存在，而CTAB与CA的摩尔比为2.03时，Fe-MOF中的介孔体积达到最大值（0.914 cm³ g⁻¹）。具有最大介孔量的Fe-MOF热解导致其碳化并生成γ-Fe₂O₃@碳材料，比表面积从3036 m² g⁻¹显著降低至387 m² g⁻¹，但平均孔径增大至5.78 nm，八面体结构解体为不规则形态的Fe-MOF（550），并使碳基体被微量氧和金属氧化物修饰。γ-Fe₂O₃@碳材料具有介孔结构，基体中主要为石墨碳（石墨与无定形碳的比例为0.79），这有助于通过2e⁻电子转移途径增加O₂电子还原的潜力。
