ZIF Catalyst Synthesized by High Energy

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modifying N-G by ZIF-8 on the electrochemical performance? Introduction. N-G & MOF. [1] S Zhuang, E S Lee, L Lei, B B Nunna, L Kuang, W. Zhang, Synthesis ...

New N-G/ZIF Catalyst Synthesized by High Energy Wet Ball Milling for Electrochemical Systems Shiqiang Zhuang, Bharath Babu Nunna, & Eon Soo Lee* Advanced Energy Systems and Microdevices Laboratory, Mechanical and Industrial Engineering, NJIT

Synthesis methodologies

Introduction The nitrogen-doped graphene (N-G) catalyst, which is one of the promising non-platinum group metal catalysts, is investigated to replace platinum group metal catalysts for the oxygen reduction reaction in electrochemical systems. This work is the second stage of a research targeted on investigating new N-G catalyst with high electrochemical performance. N-G catalysts, which were synthesized by high energy wet ball milling in the first stage, are modified by a metal organic framework (MOF) material named ZIF-8 in this work. The final compound, N-G/ZIF, is expected to have advantages of both N-G and ZIF-8 such as high catalytic activity, high specific surface area, high porosity, and high thermal and chemical stability. The modification effects of ZIF-8 on the physical and chemical properties of N-G catalysts and the reaction mechanism are studied through the characterization analyses included SEM, TEM, BET and XPS.

BET Surface Area

N-G

A schematic representation of the high energy wet ball milling approach to synthesize N-G catalyst in one step under room temperature.

b

c

N-G/ZIF catalysts are synthesized with high energy wet ball milling with N-G and ZIF-8 as reactants.

Physical Properties of N-G/ZIF http://pendientedemigracion.ucm.es/info/tuma/quimicas_ superficie/pilas.html

N-G Particle size ~300 nm

Larger BET surface area => higher ORR activity Adding ZIF-8 => enhance performance of N-G

① Effect of modifying N-G by ZIF-8 on the electrochemical performance?

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Structure of N-G

http://pubs.acs.org/doi/abs/10.1021/ja407552k

On-going Research

ZIF-8 Particle size ~500 nm

N-G & MOF

BET surface area: GO